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rgold
Trad climber
Poughkeepsie, NY
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Topic Author's Original Post - Nov 26, 2008 - 02:43pm PT
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I started this thread in an effort to protect Largo's equalette thread from clipping-the-anchor drift. Whether it will succeed in that goal, and whether there is even any interest in the issue I've excised to this location, remains to be seen.
I've included quotes from myself, stzzo, TradIsGood, DR, Peter, and Karl Baba from the equalette thread. I've also taken the opportunity to juxtapose my responses with the quotes.
The result looks a bit egotistical, since I appear to be having a dialogue with everyone else, but there didn't seem to be any way for a lowly participant such as myself to transfer over the discussion to another thread. If the subject is at all interesting to others, then the discussion will go on in the usual fashion and I will rapidly fade from any hint of centrality.
The post that began the discussion in the equalette thread is next.
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rgold: If you fall, statically belayed, directly onto the belayer (and your impact is transmitted by the belayer's tie-in directly to the anchor), then the anchor has to absorb the load of a factor two fall, say 9kN.
If the leader clips the anchor, then the fall factor is, at first, greatly reduced, but because of the pulley effect (mitigated by friction) the load to the anchor is 1.7 times the peak load in the leader's end of the rope. So, low fall factor means lower peak load, but this load is nearly doubled by the pulley effect.
As the leader gets higher above the belay anchor without anything else in, the fall factor increases, the peak rope tension increases, and the clipped anchor has to withstand 1.7 times that increased peak load. At some point, the leader reaches a ``break-even point,'' at which the leader's lower fall-factor fall, with impact 1.7 times the rope tension, equals the anchor impact of a factor-2 fall directly onto the belayer.
Once above the break-even point, a leader fall imposes a higher load on the clipped anchor than a factor-two fall onto the belayer would.
What is not generally appreciated is how close the break-even point is to the anchor. If belays are static in both cases (not a very reasonable assumption but one that allows some comparisons), the rope has a UIAA rating of 9 kN, and the leader is the standard-issue 80 kg flyer, then the break-even point occurs when the leader is half as far above the clipped anchor as the length of the belayer's tie-in. (This easy to visualize statistic assumes that the leader has clipped the power point of the anchor. If the leader clips one of the anchor pieces, then the break-even point is half as far above the clipped piece as the distance from clipped piece to the belayer's waist.)
Let's say the belayer has a 3-foot tie-in. Then the break-even point occurs when the leader's waist is a foot and a half above the power point, roughly when the power point is at the leader's knees. Once the power point is lower than the leader's knees, it will be subjected to a higher load if clipped than it would be if the leader factor-twoed onto the belayer. This is what I meant when I said the break-even point is really very close to the anchor.
If we assume a dynamic belay as a result of the rope slipping through a belay device with, say, a 4 kN slipping threshold for a particular belayer, then there is no break-even point. The peak anchor load for a factor-two fall onto the belayer is 4 kN, and the peak anchor load for the fall with lead rope clipped to the anchor is 9.7kN. (Edited to include tito's correction) This is interesting, because it suggests that a statically belayed factor-2 fall onto the belayer does not load the anchor any more than a dynamically belayed fall in which the leader has clipped the anchor.
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stzzo: rgold, I'm interpreting that the take home points are that
clipping the anchor or one of the anchor pieces can be a risky practice.
at the start of the pitch dynamic belays could be of great use.
Is that accurate?
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rgold: There are a number of issues to consider, and no single recommendation is going to cover them. What is almost certain is that clipping the anchor will expose it to higher loads, perhaps much higher loads, than not clipping the anchor, if there is a leader fall before the first piece is placed. How the party resolves that issue ought to depend on the anchor in question as well as the skills (and even the equipment) of leader and belayer, rather than on any single rule slavishly followed.
Dynamic belays are likely to be be dictated by the severity of the fall, and so will not occur as a matter of choice. Since no one practices dynamic belays any more, whatever skill might be involved in instigating and controlling them is not available. Whatever the case, a dynamic belay is an option for keeping the load low on an anchor. The only other one, proposed a while back on another thread by Karl Baba, would be to put a screamer on every piece of an anchor.
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TradIsGood: It [rgold's break-even discussion] does assume that the belayer is "static" i.e. somehow tied in such that he does not get lifted toward the power point. The dynamic case limits the load [at least until the point at which belayer reaches the power point] and is a function of the weight of the belayer and the friction at the power point, which I think is also not widely appreciated, though likely more widely understood than your analysis of the break-even point.
The alternative of belaying directly off the belayer's harness carries its own risk that perhaps is not well understood by those who most commonly set up the pulley. If the factor 2 onto the belayer occurs, the belayer must immediately (before the load) alter the position of his brake hand from below the waist to above the waist at which point he will then be absorbing a downward load.
This is an event that he may never have experienced before (especially if he is a beginner, i.e. a member of Largo's target audience). It won't happen in any toprope situation.
I fear that the belayer is more likely to fail to catch the fall under these circumstances, than the anchor is to fail. Maybe you have data or experience one way or the other?
The very few times I have been in this situation on lead, I took care to advise the belayer of the different requirements and did not depart the belay until I was satisfied that he or she understood exactly that a) the brake hand would have to go up, b) why that was so, and c) that the force of the fall would fall onto their legs and possibly pull them off his or her stance, or onto the ground.
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rgold: It is true that lifting the belayer will reduce the peak load of the fall arrest, but by how much is not clearly understood. Belay tests by the CAI suggest that you don't get as much of an effect as you might think. This is probably related to the fact that in a frictionless world, the belayer, after an initial period of acceleration, could be lifted forever at constant velocity, all of that lift making no contribution to peak load reduction.
As for the hand positions for possible factor-two falls, I have, as you probably know, posted about this a number of times. The primary argument for redirecting through the anchor, given that it will virtually always lead to much higher anchor loads, must ultimately be predicated on what I am tempted to call belayer incompetence, but so many belayers would be included in this characterization that I dare not use that term.
I certainly have no data. I have read of several instances in which a belayer lost control of the belay in a high factor fall. Whether this was due to inattention at a critical moment, improper anchoring and stance, the failure to wear gloves, or the use of an inadequate belay device, I cannot say.
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DR: Rich, could you explain what you mean by "pulley effect"?
rgold: The carabiner at the top piece acts as a pulley when a fall is arrested. Without friction, the load to the anchor would normally be double the peak rope tension. With the biner providing some resisting force in the form of friction, the tension on the belayer side of the biner is less than the tension on the leader side. Conventional wisdom seems to have settled on about 30% less, but this figure has never really been properly tested as far as I know. So rather than experiencing double the leader impact load, the top piece gets about 1.7 times the peak leader's side rope tension.
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Peter: I don't understand what force the PAS increases compared to a cordolette or sling. I belay off my harness either way, and usually clip the rope to a power point an arm's length above my waist when belaying the second and at least until the leader has a couple of good pieces in. The only time the second is clipped directly to the anchor is when we're switching leads and there's no risk of a dynamic fall. If you tie in to the anchor with the rope how much force is absorbed by the short length of rope between the anchor and your harness?
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RG: The PAs doesn't do anything in Peter's system other than act as a tether for the belayer; it will almost never be involved in transmitting anything more than the leader's weight to the anchor, and so there is almost no issue that I can see with using the PAS in this way.
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Karl Baba: I agree Peter, the PAS static issue is a non-issue.
Just like many of these geek threads that don't consider enough practical issues.
The real issue on using a PAS to connect the pieces on your belay is this: You can't escape the belay in an emergency without basically disconnecting your anchor!
Same goes for folks who use the rope to anchor directly to the pieces.
Now for folks who worry about the mechanical advantage effect of clipping the rope through the top piece of the anchor, answer me this, if you are at a hanging belay or are just putting your weight on the belay to get off your aching feet, will the multiplier effect still put twice the force on the belay. I think not. If you are hanging on the belay already, the forces on the anchor remain the same.
Personally, I belay the second off the anchor with a gri-gri. I could escape the belay in 1 second, I can haul with almost no set-up, I can take pictures without risking dropping the partner, and if they fall, it's no effort to hold them.
Then I belay the leader off my harness for better dynamics in absorbing the "real" fall,.
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rgold: Karl has been a dedicated "anti-geek" for as long as I've been a geek. I'm not going to try to defend myself, other than to at least mention that I am every bit as familiar with the practical issues as he is. And I do agree that quite often, the geeks descend, or ascend, depending on your sympathies, to a realm with little or no practical relevance. But I also sense, on the other side, a tendency to react with annoyance at geekly pronouncements as if, by virtue of some connection to science, they represent prescriptions that must be followed. Look, it is information that may be worth thinking about before you go on with your business as usual. That's all.
I'm not going to start another line of dissension on what I think is one of the most overhyped developments in climbing: the belay escape. And the hanging belay question is too poorly posed to respond to meaningfully. In any case, it does not, as far as I can tell, have anything to do with the absolutely unquestionable load-doubling, or not-quite-load-doubling, of a redirected belay.
Karl doesn't say if he keeps the anchor clipped when he belays the leader. But if you don't keep the anchor clipped, then attaching to the anchor with something like a PAS is a really bad idea, because this is the one situation in which fall energy might have to be absorbed by the tie-in. And if the anchor rigging might possibly extend which is the context in which I made a comment, then there is signifcant potential for extreme loads resulting in part from the nature of the tie-in material.
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Clint Cummins
Trad climber
SF Bay area, CA
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Nov 26, 2008 - 02:57pm PT
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DMT,
> How many belay sweeping falls have occured in this sport? I don't remember all that many.
How many would it take? I recall one in 1986 or 1987 on the East Buttress of Middle Cathedral - it resulted in a double fatality which I witnessed. I don't know the exact anchor configuration which led to the failure, but other leaders could take a factor 2 fall onto that belay.
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crøtch
climber
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Nov 26, 2008 - 03:12pm PT
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If pro isn't available to the leader early in the pitch, I'd argue for the leader clipping the powerpoint with a screamer, and making sure that the belayer's tie-in is longer than the length of the extended screamer.
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Karl Baba
Trad climber
Yosemite, Ca
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Nov 26, 2008 - 03:18pm PT
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"In any case, it does not, as far as I can tell, have anything to do with the absolutely unquestionable load-doubling, or not-quite-load-doubling, of a redirected belay.
Karl doesn't say if he keeps the anchor clipped when he belays the leader. But if you don't keep the anchor clipped, then attaching to the anchor with something like a PAS is a really bad idea, because this is the one situation in which fall energy might have to be absorbed by the tie-in. And if the anchor rigging might possibly extend which is the context in which I made a comment, then there is signifcant potential for extreme loads resulting in part from the nature of the tie-in material. "
My big complaint is that the geeks often don't write about, nor weigh the practical disadvantages versus the theoretical, mathematical advantages.
In this case, Taking a factor two fall right on your belay device (body) is the alternative to clipping the anchor (MADNESS unless you have a truly crappy belay)
Escaping the belay would be nightmare in that case and you can't lower the leader to the belay because she is below the belay. If you just clip the top anchor piece, you have so much more control and options. Where I live, that top anchor piece is usually way bomber. If now, the leader should place something asap.
I'd like to see the math on just how dynamic 2 feet of rope would be in a big fall situation. Best case scenario might be to clip in one of the loops on a regular pocketed daisy chain and let them rip out one by one like a screamer.
In any case, I suggest considering that at a hanging belay, you're weight is already on the belay, so whatever weight is already on the directional, can be subtracted from the pulley effect on the same piece
PEace
Karl
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Tomcat
Trad climber
Chatham N.H.
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Nov 26, 2008 - 03:22pm PT
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I follow these discussions carefully,and think I understand the issues.Experience has taught me,if anything 1)lot's of people are certain their anchors are bombproof,and they all are until tested.2)The problem with this type of discussion is that it doesn't really factor in the mayhem of a factor two,the sudden yank around,possible forfeit of brake hand bend back.In theory at least,clipping the anchor would keep the orientations right.
Because of the issues associated w/FF2, if I percieve much chance of one,I will sometimes move the belay DOWN a bit,and use the anchor as a first piece.I've done this on the Dike for example.In lieu of that I will take some other measure,which for me is usually to knot off the rope X # feet out with a loose knot I can remove with one hand while belaying.That way if I lose control there is a back-up.In that configuration I am Ok without clipping the anchor.Gri-gri's and munters are a cure too,as I understand it,but I don't own a Gri-Gri,and you rarely see a munter off someone's harness,or I don't.
Another solution at times,is to deal with the hard climbing just off the belay before you bring up your partner.Get it done,get some gear in,move back down to the belay stance,and bring them up through the top piece(s).If they are leading the next pitch you are all set.If you are you will have to pull the rope through.This works for me ice climbing.
My " solutions" are OK for specific climbs and situations,but don't cover just everyday sh#t happens scenarios.
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TradIsGood
Chalkless climber
the Gunks end of the country
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Nov 26, 2008 - 03:27pm PT
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Rgold, thanks.
Of course, there is friction, so even if the belayer ascends at a constant speed, some energy - friction force times distance - is dissipated.
That said, I admit I have no idea whether the peak force occurs when the belayer is accelerated, or when his speed drops to zero (I suspect that it is one or the other, and not in between?), or perhaps just after that when the rope stops stretching. Since this is not linear, I am not willing to trust my intuition here.
I guess the best advice is simply, the leader should not fall - at least not until much later.
Unless I see differently, I probably am still going to worry more about the safety of the belay, than the safety of the anchor - and try to get a piece that is not in the anchor where possible. (It has always been my goal to get several pieces in early.)
Post Tomcat EDIT.
Hey, that knot idea is cool!
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rgold
Trad climber
Poughkeepsie, NY
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Topic Author's Reply - Nov 26, 2008 - 03:27pm PT
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Dingus wrote: "Had a recent dialogue with jt512 on this topic. It is his contention that clipping the anchor as a first piece is dangerous and that an FF2 directly onto the belay is less dangerous than this 1.7 peak load thing.
I don't buy it. I'm gonna need some proof to convince me its safer as a general statement. In a bomber anchor situation - why risk an FF2 and a longer fall?
If you have a bomber anchor, indeed why not? And what if your anchor isn't bomber? Dingus, I know you've been at this game plenty long enough to know that isn't an empty question.
"Now what if that first piece were an anchor-indepentant piece, for example, 6 inches above the highest anchor piece - what's the difference? I don't see any myself - a first piece is a first piece and the top piece always sees the pulley effect?"
The first piece always sees the pulley effect. But the failure of an anchor-independent piece doesn't have an immediate consequence for the anchor, because the anchor-independent piece isn't connected to the other anchor pieces.
How many belay sweeping falls have occured in this sport? I don't remember all that many.
My count has gone up a few in recent years. I think the rate now stands at about one every five years over the past fifty I've been climbing. But I can't document that, I'm relying on memory, and don't start with the cracks...
Lastly I think the leader falling directly onto the belayer and anchor, as in a direct impact, is a worst case scenario.
It certainly is a very bad scenario. If falling on the anchor would extract it and falling on the belayer would not extract the same anchor, then it isn't the worst-case scenario.
At the end of the day It Depends.
Absolutely.
But what do I know?
Plenty.
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Clint Cummins
Trad climber
SF Bay area, CA
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Nov 26, 2008 - 03:53pm PT
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To reiterate what others have said, you can drastically lengthen the belayer's connection to the anchor, when there is hard climbing immediately above the belay, and clip the belay with a screamer/load limiter. This is what Kelly and Bruce did when trying to lead p2 of Exodus on Middle Cathedral this past summer. Bruce connected to the anchor with about 20 feet of rope, so he hung well below the bolts.
Besides increasing the height the leader can fall before increasing the load, it reduces the chance of the belayer being hit by the falling leader, or being slammed up into the rock by a hard leader fall.
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scooter
climber
fist clamp
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Nov 26, 2008 - 04:10pm PT
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Dingus-
A couple from CO. fell ALL THE WAY off of DNB a few years back when the leader either fell on the anchor or pulled a piece then fell on the anchor. I can't remember exactly.
Pat
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rgold
Trad climber
Poughkeepsie, NY
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Topic Author's Reply - Nov 26, 2008 - 04:24pm PT
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Karl Baba wrote :"My big complaint is that the geeks often don't write about, nor weigh the practical disadvantages versus the theoretical, mathematical advantages."
A fair observation. As the current and really rather unwilling geek defender, I'll say that the geeks were discussing what they were discussing. It is up to the reader to supply an appropriate real-world context. It is possible to do this without rejecting everything the geeks were saying.
"In this case, Taking a factor two fall right on your belay device (body) is the alternative to clipping the anchor (MADNESS unless you have a truly crappy belay)"
Well, I think MADNESS is in the eyes of the beholder, or capitalizer in this case. As someone who has held a factor-two fall, I don't recall much in the way of mental instability either before or after the event, but of course you can't trust the inmates to run the asylum. And so it comes down to what the known capabilities of the belayer are and whether a less-than-perfect anchor is worth subjecting to, say, double the load it absolutely has to be subjected to.
A less-than-perfect anchor is different than a truly crappy anchor. It would be MADNESS for the leader to clip a truly crappy anchor. It is sensible for the leader to clip a bombproof anchor. Now between those extremes is where it makes sense to think about balancing opposing concerns before just doing what you always do.
I'd like to see the math on just how dynamic 2 feet of rope would be in a big fall situation.
A request for geekly services? I am honored...but unfortunately I don't know what you are asking here.
in any case, I suggest considering that at a hanging belay, you're weight is already on the belay, so whatever weight is already on the directional, can be subtracted from the pulley effect on the same piece
According to this logic, if the belayer and leader are just hanging from the top piece (no fall involved) then the belayer's weight can be subtracted from the total load on that piece and presto---there is no such thing as the pulley effect, a conclusion that can be disconfirmed in all sorts of reality-based practical ways.
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hafilax
Trad climber
East Van
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Nov 26, 2008 - 04:28pm PT
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Had a recent dialogue with jt512 on this topic. It is his contention that clipping the anchor as a first piece is dangerous and that an FF2 directly onto the belay is less dangerous than this 1.7 peak load thing.
I don't buy it. I'm gonna need some proof to convince me its safer as a general statement. In a bomber anchor situation - why risk an FF2 and a longer fall?
Now what if that first piece were an anchor-indepentant piece, for example, 6 inches above the highest anchor piece - what's the difference? I don't see any myself - a first piece is a first piece and the top piece always sees the pulley effect?
How many belay sweeping falls have occured in this sport? I don't remember all that many.
Lastly I think the leader falling directly onto the belayer and anchor, as in a direct impact, is a worst case scenario.
But what do I know?
DMT
I would rather place another piece instead of clipping the highest piece. Should that piece pull I would rather fall onto a complete anchor than one that had a piece pull.
As for clipping the highest piece? That depends a lot more on the situation. I wouldn't do it as a matter of practice. If I didn't trust that piece 100% but it best protects the climb then I might try to change the anchor in order to make that piece independent.
From rgold's model I found that the force on the anchor is greatest if it is clipped and that the force on the belayer is greatest if it isn't which really does make sense to me. Pick your poison.
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Karl Baba
Trad climber
Yosemite, Ca
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Nov 26, 2008 - 04:28pm PT
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Great advice clint!
Anchors fail once in awhile but it's dang rare. Dropping the leader happens a lot more and your chances of doing so increase if he falls right on your waist via a factor two. Why? Because it's hard!
There is no evidence BTW that the DNB anchors were clipped as directionals. Thing is, with the forces involved in climbing, a really crap anchor pulls no matter what and a bomber anchor stays no matter what. I'd be surprised if the grey are of anchors that may or may not pull was very large
PEace
Karl
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G_Gnome
Trad climber
In the mountains... somewhere...
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Nov 26, 2008 - 04:30pm PT
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I for one would always rather have directional control when holding a high load fall. Besides, the dynamics of the catch when the rope is pulling the belayer up versus pulling straight off the belay look in a hanging belay does not intuitively argue for the later. You would have to prove to me that in a real world application that it is preferable to catch on the belay loop in a very un-dynamic way.
Also, in all the cases that I remember where a leader fall cleaned both the leader and the belayer off the wall the belay was quite questionable and/or the facts of the failure were very unclear - perhaps to protect the guilty.
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Peter Haan
Trad climber
San Francisco, CA
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Nov 26, 2008 - 04:58pm PT
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For those who still dont comprehend how the top piece in a protection system or anchor sustains a load greater than the load that is hanging from it (say a climber or haul bag), consider this.
If you tie yourself off to an anchor, the anchor experiences only your total weight. Similarly, if you are standing on a ledge and want to haul a heavy bag up from the ground with a line directly connected to it, say a 100 lb weight, you have to pull hand-over-hand 100 lbs (plus a bit for friction if there is any with the bag dragging on surfaces or whatever) to start to move that weight upwards.
But say instead you put a pulley at the ledge and run the haul line through it and then you go back to the ground where the haul bag is and haul on that line from there hoping to make the bag go upward, consider this: The bag weighs 100 lbs and you have to pull a bit more than 100 lbs to move it up, but the pulley experiences nearly 200 lbs because of the loads on BOTH ends of the haul rope that it supports have added up for the poor pulley.
Again, if you just tie the bag off to the pulley or a fallen leader off to his high piece, the pulley or highest piece only sustains a load of just what hangs on it of course.
This basic principle also applies when a climber takes tension FROM the belayer through the rope while leading.
And in very hard direct aid it is not smart to take tension from the belayer via the rope but to daisy off of your piece to rest, be supported for the next placement, etc. as tension from the belayer unnecessarily develops quite a bit more load on bad placements than might be understood and may blow them.
The simple mechanics here are not so intuitive and often lie hidden in situations where the participants would be better off being aware of the forces that magically develop.
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Peter Haan
Trad climber
San Francisco, CA
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Nov 26, 2008 - 05:07pm PT
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I like this cogent discussion.
We always need to vet abstract discussions in at the reality counter; I think this is happening here fortunately.
For at least 4 decades in practice any experienced climber nearly always has been getting pieces in asap right above a belay even on easier climbs. We have historically clipped to the anchors separately (so to not saw through slings) but immediately established a separate new nearby piece (whenever possible) for to get two points at this belay redirect and with this discussion about the near doubling of forces on the highest piece in a fall situation, this practice of a separate redirect piece becomes extremely sensible where it is obtainable. And having clipped both anchor and redirect, you have built friction you really need if a fall happens early. At any rate it should never be possible for the leader to directly fall on the belayers device.
And I would add that anchors nowadays are incredibly much better than they were even just three decades ago, so mostly they are correctly perceived as bombproof. Even people who dont understand the basic physics here (and that is most people as it turns out) still like to put a piece in right away, because they intuit it is somehow better in practice. Good.
The frequent discussion of fall potential evaluation via the Category model is really good for everyone and should continue to be in the forefront.
Along with the group here, I can only think of one or two accidents where a belay was swept away, both climbers going to their maker in all these years, so given how very very rare the event is, perhaps the bigger point is the damage done to the belayer successfully holding a Cat 2 fall.
I agree with the group that difficult belay escape is also very rarely required even though it has to be kept in mind.
I think Crotch is right with his modern suggestion of using a Screamer at the first point or if the anchor is clipped for redirect as a matter of course in leading. The things are cheap, small, light, common and produce a remarkable reduction in Kn. Most modern belay devices can easily produce static belays in spite of the need for a dynamic one so screamers help out belayer error there as well. So as protocol it would be a great standard.
Anchoring in an exaggerated elongated fashion as Clint relates here, is an example of a clever and special case of developing belays that are the best in uncommon situations, and which cases we all should be considering and hearing about etc. rather than thinking as most do, that there is basically only one form to safeguard a leader. I like some of those grounder climbs where the belayer is unanchored and hopes to run down the hill to eliminate slack if the leader falls, too!
Anyway great thread, and Richie is as clear as ever! Thanks.
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jstan
climber
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Nov 26, 2008 - 05:17pm PT
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"rgold: It is true that lifting the belayer will reduce the peak load of the fall arrest, but by how much is not clearly understood. Belay tests by the CAI suggest that you don't get as much of an effect as you might think. This is probably related to the fact that in a frictionless world, the belayer, after an initial period of acceleration, could be lifted forever at constant velocity, all of that lift making no contribution to peak load reduction."
One piece of data.
Many years ago I ran some 8mm perlon through an 18" length of plastic pipe which had a cross-wise window cut in both sides with an end mill. Then I pushed a finishing nail cross-wise through the rope in the window and also put in a finishing nail so the rope was fixed at one end of the pipe. Then I put a spring bronze clip on the pipe so that under load the nail in the window would push the slip to a new position. By measuring the final location of the clip I could determine the peak instantaneous load. i calibrated this unit in a tensile machine so the rope had had a few cycles on it. It did not show a lot of stress aging in its stress strain relation. By measuring the final position of the clip I could measure the peak instantaneous load.
Just right of Something Interesting there is a small ceiling maybe, what, forty of fifty feet off the ground. Slightly below that ceiling there was fixed pin to which I clipped the unit describer above so that when i dropped a 165# pound duffle bag filled with shale (tied in at the middle with a swami of 1" tubular) from a position above the ceiling it would travel perhaps forty feet before the rope came tight.
When I was anchored to the big tree at the base and acted to belay the "fall" my unit indicated a peak force at the top piece of about 500#.
When I tied the rope off at the tree we got a peak force of about 1000#.
I have not seen the CAI data but my experience convinced me having the belayer whipped about does all kinds of good things for the system. Personally I would never consider clipping a belay device directly to a fixed anchor.
As to the main question, I would never clip a top anchor as a directional if I had any doubts about it. If the top anchor is good and if there was any chance of a fall, I would clip it as long as it was far enough away from me so that when I got catapulted it would not interfere with my belaying. Most of the calculations one makes in assessing how to give the belay get wiped out when you are suddenly going head first down the hill. Had I no directional I would belay directly to catch a FF=2 and reverse my position as soon as a good piece was in.
As an aside, climbing with Richard was a special case. Directionals were not needed.
EDIT:
Perhaps an addendum to my "having any doubts as to an anchor" is in order. This is about the only point where I differ with some of the contributors to this very useful thread.
This thread is about numbers but when we come to discussing the strength of an anchor in rock on a climb we don't have any numbers. There is a very real disconnect between the two parts of the discussion. Well when I was dropping bags of shale I was also engaged in testing actual placements up to 3000# using a portable hydraulic rig I had built. I was able to take real situations and put numbers on a lower bound for the yield point. So when throwing simulated climbers into forty foot falls produced forces on the top anchor well under my lower bounds, I began to feel as though questions were being answered.
Frankly it also made a difference in my climbing. That time I had a single stopper for protection I felt pretty confident. Based on my hydraulic tests and the relatively small amount of shear I saw in all those tests led me to believe the critical nut in this case was easily good for 1000#. As a backup my belayer weighed only 110# and I had specifically not tied her down. Into the bargain I had her stand out from the base of the rock so the initial motion would be lateral. The belay would start out soft and naturally become stiffer. I expected the belay to be quite dynamic. The nut was not going to have to withstand anywhere near 1000#. I have since seen cases where similar strategies are employed for poorly protected grit stone problems.
When Helmut Microys came back from Mammut with these fall factor calculations I thought they were good for qualifying rope and possibly for worst case situations such as coming off a belay. But do we really think 10kN would not break us in half? To test a nut once I foolishly did a FF1 drop of 18" onto a sling of 1" webbing. Nearly killed me. A ten foot drop onto five feet of rope tied to an eyebolt in structural steel? You'd be history. Without a doubt. The very next day I started building my hydraulic rig.
Whatever you do I think you really need to avoid having serious unscheduled changes in direction.
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pyro
Big Wall climber
Calabasas
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Nov 26, 2008 - 07:02pm PT
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I always clip a directional.
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Patrick Oliver
Boulder climber
Fruita, Colorado
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Nov 26, 2008 - 08:16pm PT
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I have about a hundred things I could say, after reading through this thread, but I'm not sure I have the energy to do more than add a few tidbits from the peanut gallery. I don't know how many people have had the kind of experience I've had at holding serious falls. The first major one was Kor leading above me, in a lieback, when he pulled off a block and went sailing past me, as I stood on a small stance on a near vertical wall... Soon after he took an even larger fall from higher above and went far past me and below... Then I caught Dalke in a nasty freak fall off a climb in Eldorado he never normally would have fallen off. I then caught Dalke on a route on Castle Rock... Then with Rearick, as he went liebacking up a 5.10+ overhanging crack, his feet on lichen, strung out with a marginal bong half way between him and me, and he slipped... I could go on and on, but I began to feel somewhat of an expert at the realities of such falls and such forces. I developed a mindset to be always prepared, no matter the skill level of my partner.
Of course Peter hit it on the head, if I understand his term "power point," in saying a belayer needs a point to run the rope through independent of the belay and independent of the leader's protection, presumably in most cases just above the belay, or possibly to the side if the next pitch is a traverse... Such a point, if one can get it, could make all the difference.
If I've learned anything through the years, no situation is like any other. You can't exactly make rules that apply in all cases. One has to examine every situation separately and set things up appropriately. A bad mistake is to get into that habitual mentality, where you simply do the same thing at every belay that you always do, a kind of mindless routine approach. Staying awake is vital and to look and think and not follow any rule if it doesn't apply.
I have always felt (or through an evolution of experience came to believe) if any sort of mastery at the belay is to be achieved it might be to imagine at each belay point that there is no anchor at all. To envision such a thing, which may seem a bit absurb (and of course doesn't work in all cases), makes you find the position where your body is in the best place and you face the right way and so forth and so on, and have the best chance of holding a fall. Then, the anchor set-up is added, in relationship to that idea. Too often, I think, people rely solely on the anchors or their belay device, or some or other form of mechanical appartus, as the strength of their belay. They don't even think about body position or of catching a fall and instead leave it to the gear to do the job. I have found the belay is much stronger by relying on oneself first, and secondarily the gear -- as a general rule.
No matter what the forces are, or what they measure in terms of numbers, assume it will be significant, and don't take anything for granted.
The leader too plays an important role, in a strong belay, by being especially careful to get the right gear in, to think about the belayer, in the classical mountaineering fashion of considering one's partner above oneself. Sometimes when I lead I am positive I'm not going to fall, but I always think about my belayer and what would happen should the farthest thing from my imagination happen. I've known very good climbers who have more or less felt the belay was the belayer's job and the belayer's responsibility, and took no interest in any "possible contingencies" but rather focused solely on the rock ahead. It is always a joy to be with one who has that special integrity to exercise whatever necessary restraint to make things safe, no matter how difficult the climibng is.
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jstan
climber
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Nov 26, 2008 - 08:23pm PT
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Hump? What hump?
Name the movie?
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Karl Baba
Trad climber
Yosemite, Ca
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Nov 26, 2008 - 08:31pm PT
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Rgold wrote
" And so it comes down to what the known capabilities of the belayer are and whether a less-than-perfect anchor is worth subjecting to, say, double the load it absolutely has to be subjected to. "
I dispute that it would be double the load, merely the load plus the weight of the belayer, after all, the leader is the only one flying at 32 feet per second squared.
Rgold writes
"in any case, I suggest considering that at a hanging belay, you're weight is already on the belay, so whatever weight is already on the directional, can be subtracted from the pulley effect on the same piece
According to this logic, if the belayer and leader are just hanging from the top piece (no fall involved) then the belayer's weight can be subtracted from the total load on that piece and presto---there is no such thing as the pulley effect, a conclusion that can be disconfirmed in all sorts of reality-based practical ways. "
No, According to this logic, if the belayer and leader are just hanging from the top piece (no fall involved) then there is the weight of two people on the top piece. It doesn't matter if they are hanging on the piece with separate daisy chains or connected to each other by a rope.
peace
Karl
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Ed Hartouni
Trad climber
Livermore, CA
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Nov 26, 2008 - 10:21pm PT
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the power of a scientifically correct analysis is that it does not depend on common belief, rather, it has to be explainable in a rigorously logical manner and obey physical law.
That being said, most climbers do not care or think about the forces involved in a rare fall (unless you're climbing with Pat, apparently - humor). Instead, climbers utilize a "skill of the craft" approach to building anchors. How you lean this, and what you lean is very dependent on who your mentor is... many of us learned it from someone who was an experienced climber, usually the older ones of us... many others learned it from a book.
What most of us have in common is that we have not been tested on the anchors that we have built. Over the last 13 years I've built 1000s of anchors. In most cases they were not tested by large force falls. Does that mean that all those anchors would have protected me and my partners in the event of a large force fall? I have no way of knowing.
I do pretty much what everyone else does:
 Be thoughtful about where the belay should be with respect to bringing up the second, and belaying the leader on the next pitch.
Select features in the rock that have mechanical integrity, and are not mechanically related.
I try to get three anchor points in, where any of those three would hold the entire fall.
I usually try to "equalize" the anchor system so that the forces are distributed on multiple anchors.
Get a piece of pro in very close to the belay, "protect the belay" I say, where that piece will hold a fall all by itself.
These days I do this all pretty quickly. It is informed by scientific analyses I have done and it doesn't look a whole lot different than what I believe is taught (though there is a difference between what the teacher thinks was taught and what the students learned, especially if there are no tests).
Answer the OP question? "Should the leader clip the belay anchor?", of course it depends. If you can get another piece in, do that. If it is a 3/8" bolt, probably fine to clip... if things are dicey enough to make you worry, then you have to think the whole anchor is sketchy and you have to be really careful leading out to that first piece, or if that isn't possible, maybe just backing off, or moving the belay to a better place.
We make all these choices largely based on our experience and our willingness to accept risk, risk that may not be calculable.
The geeks do have to listen to the cool-cats, but the cool-cats should listen to the geeks as well, good information all around.
Unfortunately, there is very little real good work done to examine our practices. jstan did once upon a time, and Wootles (avatar RIP) had also... we have the misfortune of worrying about this only when one of ours has made a fatal miscalculation...
...then we move on.
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JohnRoe
Trad climber
State College, PA
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Nov 26, 2008 - 10:39pm PT
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I ran some numbers (numerical integration of the equations of motion). These need checking when I am more awake, but they seem plausible. (Edited to give a more plausible rope modulus.)
Karl asked (in the equalette thread)
"1. Let assume the leader clipped the powerpoint of a cordalette anchor as a directional, climbed up 15 feet and fell. The belayer is also hanging low on the cordalette.
versus
2. The belayer is hanging there and belaying off the powerpoint with a gri-gri (assume static belay even though they slip a bit)
How much pully effect in #1 versus #2"
Here are 3 scenarios. In each scenario the belayer is hanging 1 meter below a power point and has 4 meters of rope out to the leader. Assume rope modulus=11.2kN (EDITED) and coeff of friction round top piece = 0.6 Assume 80kg climber and belayer
Scenario 1. No runner: factor 2 fall onto the belayer.
In this case the peak retarding force on the falling climber of 6.8kN is generated 287ms after impact. The peak force on the anchor is then 7.6kN (retard force + weight of belayer)
Scenario 2. Runner through the power point; belayer static (anchored for upward pull).
The peak retarding force on the falling climber is now 6.2kN, 283ms after impact (slightly lower b/c of lower fall factor). The peak force on the anchor is 1.6 times 6.2kN, that is, 9.9kN.
Scenario 3. As scenario 2 but no upward pull anchor; belayer is hanging.
This is the softest catch because the upward movement of the belayer absorbs some force. The peak retarding force on the falling climber is now 5.2kN, generated 228mS after impact. At this instant there is an additional 3.1kN on the belayer, who is headed upwards at approximately 3.5m/s. Thus, the peak total force on the anchor is 8.3kN, still more than in scenario 1. After 372ms, the belay device gets sucked at high speed into the biner on the power point. I didn't attempt to write any equations for what happens after that :-)
I can run more of these if anyone wants (or someone else should check them!) All of these impact forces would be bad news; perhaps we should try again with less rope out. (Edit: looks more realistic now the rope modulus is corrected)
JohnR
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Patrick Oliver
Boulder climber
Fruita, Colorado
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Nov 27, 2008 - 12:20am PT
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I still don't use a belay device and prefer a hip belay, with a carabiner to clip the leader's rope on my swami on the opposite side of the brake hand. Probably sounds archaic, but it has always worked. I mention this only because clipping the anchor would be a bit redundant, in most cases, or unnecessary, with my system and might put the burden of a fall more on the anchor than on me. Unless the anchor is really bombproof, and maybe a triple anchor kind of thing, I can't really imagine clipping the lead rope into it, as I would rather trust myself to hold a fall and let the belay anchor back me up and anchor me to the belay place. I feel a little like someone from the stone age talking to the modern world. I can't imagine anyone would pay any mind to what I say. But they used to call me the master of safety -- an honor in some circles and a dubious distinction in others...
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crøtch
climber
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Nov 27, 2008 - 12:47am PT
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"I feel a little like someone from the stone age talking to the modern world."
I'm enjoying this glimpse into the mind and ways of australopithecus eldoradus.
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nick d
Trad climber
nm
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Nov 27, 2008 - 12:58am PT
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As ususal, Mr.Stannard asks the most pertinent question.
Answer up, wannabes! If you dare.
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Curt
Boulder climber
Gilbert, AZ
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Nov 27, 2008 - 01:18am PT
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It's simple. rgold is correct in theory and jstan is correct in practice.
Curt
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Karl Baba
Trad climber
Yosemite, Ca
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Nov 27, 2008 - 01:23am PT
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John, if you could run one more scenario, Factor two fall when the belayer is belaying with a gri-gri directly off the powerpoint, but is hanging on the anchor. (possible aid climb scenario)
Thanks
Pat wrote
"I feel a little like someone from the stone age talking to the modern world."
How much are you of the school of "the leader must not fall!"
It's got to be hard to catch a factor 2 fall with a hip belay when the leader falls behind you and all that force rips into a carabiner clipped into your swami (anything to keep it from sliding back your swami?)
It's true in the modern age that many climbers are more willing to fall long and hard and this just won't wash anymore. I took a factor two fall past my belayer using a hip belay BITD on the second pitch of Mud Flats and it burned his hand.
Peace
Karl
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rgold
Trad climber
Poughkeepsie, NY
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Topic Author's Reply - Nov 27, 2008 - 01:51am PT
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Uh, Karl, the calculations you just thanked JohnR for use the very same pulley effect (mitigated by friction, as I also suggested) you just got done denying. Maybe you're just picking on me? (Boo hoo!)
I did the same calculations about a year ago, including also the break-even ones whose mention seemed to start this debate. I'll have to go back and look at them, but I remember the numbers coming out a little lower, quite possibly because I chose different parameters to start with. John gets a factor two peak load of 14.8 kN, which is well above the UIAA limit for single ropes, and the fall factor of 2 rather than 1.78 wouldn't account for this, if, say, you start out with a rope with UIAA impact force of 9 kN. (I know, they come out of the box with less than that, but on the other hand are almost certainly not that resilient in the field, especially after a little use.)
Happy Thanksgiving everyone. May your anchors, clipped or not, and the rest of your lives for that matter, live up to all your fondest expectations.
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Ed Hartouni
Trad climber
Livermore, CA
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Nov 27, 2008 - 01:54am PT
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have a great thanksgiving Richard,
berg heil!
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WBraun
climber
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Nov 27, 2008 - 01:55am PT
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May your anchors, clipped or not, and the rest of your lives for that matter, live up to all your fondest expectations.
I like that line, and thanks Richard for just being here.
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SteveW
Trad climber
The state of confusion
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Nov 27, 2008 - 02:09am PT
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Wonderful information, you smart people.
I try to do it as you say, and fortunately through the
years it hasn't been tested to the limit.
This is a valuable thread and should be required reading.
Thanks!
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Patrick Oliver
Boulder climber
Fruita, Colorado
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Nov 27, 2008 - 08:35am PT
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Karl,
In a few hundred thousand climbs I've never had that happen, to have someone fall behind me and rip a carabiner around the back. If they first of all start with some kind of decent piece of protection, that won't happen. But if they have to run it out right off the belay, then I position myself so as to be in the right place and facing the right way. Maybe that sounds self-righteous. I hope not. But also if the carabiner is in the right place, it tightens where it is and doesn't slide. It sometimes amazes me when I climb with people who have all the newest gear and gadgetry who can't comprehend how I could survive using the system I do. We weren't so much from the school of "the leader shall not fall" as much as that the leader and belayer work together, that competence and technique and ability to downclimb, and creative ability to protect, and things such as judgment, etc.... contribute to the safest possible ascent. Even on a climb such as Twilight Zone, the safety was in the leader's ability. Pratt's protection was his skill more than any equipment. I would venture a pretty comfortable guess that I am able to belay with my archaic system as well as any climber around with more modern methods. But it takes a few years to learn all the things one needs to know, regardless of the methods you use. It's just another area of mastery one has to achieve. I have known very good climbers who were almost incompetent at certain basics, such as the proper belay... Sacherer was kind of an example of this. He could do those hard pitches but was famous for making mistakes at belaying, anchoring, protecting others, etc.
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TradIsGood
Chalkless climber
the Gunks end of the country
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Nov 27, 2008 - 09:32am PT
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JohnRoe,
If the belayer's fingers are on the rope above the belay device (non-brake hand), I can tell you what happens. He likely was already gripping the rope and is more likely to squeeze harder in the short instance he has than to let go. It's too late to let go by the time he realizes the error. He gets a compound fracture of the finger that hits the power point, and likely complete tears of tendons (or worse). The next finger down may be injured as well, but much less likely to be fractured. How well the hand can be repaired depends.
The pain will cause him to check his hand to see if the finger was severed. We hope that he retains a grip with the brake hand.
Anyway, Happy Thanksgiving.
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Paul Martzen
Trad climber
Fresno
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Nov 27, 2008 - 11:15am PT
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Happy Thanksgiving!
This is a fascinating thread, and I am really enjoying reading it. I especially appreciate Patrick Oliver's perspective and thoughts.
The position of the belayer's body is something I tend to think about also and it is not unusual for me to use my body as the entire anchor, particularly in scrambling and canyoneering situations. But I love the way you put it, Patrick, to start off thinking about where to position your body first, as if the belay had no other anchor, then go back to establishing additional anchors.
The original question of whether to clip the anchors as the first lead runner is interesting and one I don't think I have thought about much. I am going to try to follow the Geek calculations myself, but probably not before the thread dies. This discussion is giving me a bunch of interesting ideas for empirical simulations though. A question that seems really interesting is, "How big of a fall can you hold, without blowing out very weak anchors?" I have had some super weak anchors at times which thankfully did not get tested, but I recall thinking my body was a big part of the anchor system. Some of the techniques that people have suggested though, are completely new to me. Very cool.
Now I am off to go hike around Zion NP in the rain. My wife and I are visiting her father in St. George this Thanksgiving weekend.
Paul
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guyman
Trad climber
Moorpark, CA.
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Nov 27, 2008 - 11:18am PT
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We weren't so much from the school of "the leader shall not fall" as much as that the leader and belayer work together, that competence and technique and ability to downclimb, and creative ability to protect, and things such as judgment, etc.... contribute to the safest possible ascent. Even on a climb such as Twilight Zone, the safety was in the leader's ability. Pratt's protection was his skill more than any equipment. I would venture a pretty comfortable guess that I am able to belay with my archaic system as well as any climber around with more modern methods. But it takes a few years to learn all the things one needs to know, regardless of the methods you use. It's just another area of mastery one has to achieve. I have known very good climbers who were almost incompetent at certain basics, such as the proper belay... Sacherer was kind of an example of this. He could do those hard pitches but was famous for making mistakes at belaying, anchoring, protecting others, etc.
Really good discussion going on here, Patrick hit the nail on the head with this one. IMHO.
I have always thought that climbing is more about your brains and judgment than about the shinny newest piece of gear.
but what do I know?
..
Happy Thanksgiving to all.
GK
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sibylle
Trad climber
On the road again!
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Nov 27, 2008 - 11:34am PT
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One question I have, which has not been discussed much, is what if a much smaller climber is belaying much heavier leader? Such as women who weigh 100 - 130 pounds belaying much heavier men?
I've been in serious situations with this weight issue. A few years ago, my climbing partner (6'5", 215 pounds) took a very long fall, but he was close to 180 feet out, so there wasn't much impact. I'd guess he fell about 150 feet and ended up hanging below me. I was able to escape the anchor, and move up about 70 feet to his last pro (a sling around a tree), but could not move him. I had my old nuts on slung perlon, which I used as prusicks, to both escape the belay and to move up.
I talked to him below me, and tried to help him move up to a ledge, but could do nothing. He died three hours later.
I've always wondered since then what one could do, but without carrying pulleys, extra cord, stuff to make anchors, etc., not all of which the second usually carries, it's hard to raise a fallen leader.
I always clip leaders through the anchor, because they are usually heavier than me and I worry about catching someone much heavier if they fall below me and fall onto my harness.
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Ryan Tetz
Trad climber
Flagstaff, AZ
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Nov 27, 2008 - 12:39pm PT
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I didn't have time to read this whole thread but one thing that is IMPORTANT:
Have any of you seen the rigging for rescue video on the daisy chain and sling drop tests? They tested the metolious PAS too.
SPECTRA DAISY CHAINS BREAK UNDER A STATIC DROP OF 2 FEET WITH A 150LB WEIGHT!
That means just jumping off the ledge at the anchor the average guy will rip one of those in half. Take a factor 2 and you got no chance, and how many climbers do you know that use those things to anchor themselves? Probably more than you can count on both hands. Teaching them to clip the belays is the only thing holding the party from the ground if the belay has to hold a real factor 2.
The PAS, nylon, and spectra slings and daisy chains were all tested. While the fancy ones like yates daisys with screamers built in held a little higher they all failed when they dropped the 200lb weight 2 feet. Even the PAS.
The only thing that held up regularly were nylon daisies and nylon slings which many climbing shops have stopped carrying in favor of the new sexy light stuff. The rationale was that nylon stretches while the spectra and dyneema are totally static.
The only recommended tie in by AMGA guides to a single anchor is the climbing rope. A clove hitch tied correctly with the load strand toward the spine or a 8 on a bight. If don't do this you got to clip in twice with say the rope and a sling.
When I climb with half my buddies still insisting on carrying the daisy chain. I insist they tie in again to the anchor with the rope up higher or use a second sling or I will not leave the belay PERIOD.
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tito
climber
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Nov 27, 2008 - 02:30pm PT
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> SPECTRA DAISY CHAINS BREAK UNDER A STATIC DROP OF 2 FEET WITH
> A 150LB WEIGHT!
> That means just jumping off the ledge at the anchor the average guy will
> rip one of those in half. Take a factor 2 and you got no chance
So are you recommending that people not lead out on daisy chains?
> and how many climbers do you know that use those things to anchor themselves?
One.
> Teaching them to clip the belays is the only thing holding the party
> from the ground if the belay has to hold a real factor 2.
No matter how many times I read that, I have no idea what that means. Translation please?
Consider this: I clip in tight to the power point of a cordalette anchor with a daisy chain. My belay device starts slipping at 3 kN. I belay the leader directly off my waist. The leader falls before getting any pro in. Are you saying that it is highly likely that we are both going to hit the deck?
> The only recommended tie in by AMGA guides to a single anchor is
> the climbing rope.
The AMGA is now recommending single anchor belays?
> When I climb with half my buddies still insisting on carrying the daisy chain.
> I insist they tie in again to the anchor with the rope up higher or use a second
> sling or I will not leave the belay PERIOD.
What does making them clip in with a second sling get you?
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Karl Baba
Trad climber
Yosemite, Ca
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Nov 27, 2008 - 02:54pm PT
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RGold wrote
"Uh, Karl, the calculations you just thanked JohnR for use the very same pulley effect (mitigated by friction, as I also suggested) you just got done denying. Maybe you're just picking on me? (Boo hoo!) "
I thanked him for taking the time. He didn't address my scenario and it should be obvious from the numbers that he came up with that they are sheer geek numbers with little relation to reality. Obviously these anchors aren't going to get 10-20kn forces under almost any circumstance. Everything would break! Now, there is SOME chance that we can take some relative wisdom from John's numbers, just in relation to each other, but because each scenario has so many unaccounted factors, who really knows?
Theoretically, a daisy fall should break your body. I've taken a few and they didn't. It's complicated.
Which is what bugs me about these threads. The number and forces that geeks come up with just can't account for all the friction, give, and ju-ju that are all over the system so they reach conclusions that don't match the obvious. Folks should be having their anchors and belays fail all the time but those things are actually quite rare in reality.
I think the geeks would be better off studying psychology and communications, which are almost non-sciences but could be more accurate in predicting climbing dangers. What really happens? Stuff like the leader falling because he expects to be lowered from the chains while his belayer thinks a rappel is next. Stuff like slipping off the descent ledge or going off rappel before clipping the next anchor. Factors of inattention and fatigue are the real climbing killers. These geek threads have their place. I'm not saying don't write in them. You just have to put up with me interjecting this bit of disclaimer in them.
I don't deny the pulley effect, just that it doesn't double the force on the anchor and that if you are hanging on the anchor anyway and belaying through the powerpoint, it adds even less to the issue.
Which John nor you haven't really addressed. Tell me. If two guys hang on one piece using their separate daisies, how much less force is exerted on that piece than if those two guys hang on that piece using a rope that connects them? Get it?
Thanks for your response Pat. Obviously, when an experienced person does what they know within the limits of the climbing where what they know works, then they have a system that works for them. I doubt your system would be good for somebody working 5.13 routes, taking repeated 50 foot whippers, like we see on some routes these days, but then, if that were you climbing like that, I'm sure you'd adjust your gear accordingly.
Peace and Happy Thanksgiving. I'm grateful there is a God and Karma, which is why this dangerous climbing stuff doesn't kill a dozen of us a day! It's amazing there's not thousands of people dying on the highways every day!
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WBraun
climber
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Nov 27, 2008 - 04:08pm PT
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The Purcell prussik system works pretty good and is what I use for daisy on free climbs. In the example below it says use 6mm but mine is 7mm and 8mm would be even better. I'm gonna change mine to 8mm soon. Since it's fast and adjustable on the fly it's ideal and it's nylon without the problematic properties that spectra and dyneema exhibit.
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healyje
Trad climber
Portland, Oregon
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Nov 27, 2008 - 04:33pm PT
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Ryan - it's another topic for another thread, this is a different discussion. That topic has been discussed extensively on other threads both here and on RC however. The short answer is, as you noted, always tie-in with the rope.
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Largo
Sport climber
Venice, Ca
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Nov 27, 2008 - 05:13pm PT
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This is great info but I need to derive from it some practical rules of thumb, even if they are provisional.
So far there are (broadly speaking) two potential failures and four possible scenarios.
The potential failures include:
1) the belay itself failing, meaning that a leader fall will generate so much force that the belayer will not be albe to hold said leader fall, the belay will fail and the leader will pitch to the end of the rope, and,
2) the falling climber will generate such peak force that when the belayer arrests the falling leader via the belay, the forces transmitted to the anchor will cause it to fail, "sweeping" the team off the face.
The four scenarios are:
1) the anchor is sh#t and there is no chance to place a "Jesus Nut" (first piece of pro off the belay) for at least 20"
2) the anchor is stout and there is no chance to place a "Jesus Nut" (first piece off pro of the belay) for at least 20"
3) the anchor is sh#t and the leader can set a sound Jesus Nut straight off the belay
4) The anchor is stout and a Jesus nut is available right off the belay
The question: In light of the "possible failures" (belay failure and anchor failure) and given these 4 scenarios, when should the leader run the lead rope through the anchor, and when should he avoid doing so?
Happy Thanksgiving, Peeps!
JL
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healyje
Trad climber
Portland, Oregon
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Nov 27, 2008 - 05:33pm PT
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Karl Baba: "Thing is, with the forces involved in climbing, a really crap anchor pulls no matter what and a bomber anchor stays no matter what. I'd be surprised if the grey area of anchors that may or may not pull was very large"
I have to take great exception to this line of thinking. As someone who still regularly free climbs above aid gear and pre-slices screamers at various angles to vary their loading dynamics, I explicitly view managing all of the various "grey areas" in climbing as the very reason why one would develop the exact [ancient] sensibilities Patrick Oliver describes in his "evolution".
Peter Hann: "And I would add that anchors nowadays are incredibly much better than they were even just three decades ago, so mostly they are correctly perceived as bombproof."
If you are talking 3/8" and 1/2" SS two / three bolt anchors, then yes. If you are talking trad anchors then I'd say it's actually often a case of 'worse and worser' as climbers who start in gyms and sport attempt to 'cross-over' to trad.
jstan: "Personally I would never consider clipping a belay device directly to a fixed anchor."
Amen, brother! In general I consider this, a commercial activity at best, and one that breeds entirely the wrong long-term 'sensibilities'; at worst, I think it's slovenly in a way that divorces you from any number of sensory pathways to knowing what is going on with your partner. I only even redirect under rare circumstances.
Patrick Oliver: "I could go on and on, but I began to feel somewhat of an expert at the realities of such falls and such forces. I developed a mindset to be always prepared, no matter the skill level of my partner."
In these discussions I always wonder how many folks have actually held falls directly onto their belay. Patrick is talking from experience and I believe jstan has said he has as well, as have I several times. In my case the result has been the same as I'm interpreting it was with Patrick - such falls aren't exceptional edge cases, but rather are simply another 'catch' - albeit, ones which set your standards and mindset for every belay you do.
Patrick Oliver: "A bad mistake is to get into that habitual mentality, where you simply do the same thing at every belay that you always do, a kind of mindless routine approach."
Another 'amen, brother!' This is another problem area for folks who are crossing over from the [monochrome] world of gyms and sport - the 'sameness' of their experience leaves them at first grasping for the "rules" of trad climbing so they can apply them. It's very hard for them (and even many trad climbers back in the day) to understand that every single circumstance is unique - that rather than 'rules', you have to extrapolate or transpose from out of a depth of knowledge and experience and onto each new situation in turn. In essense, the 'rules' by themselves have limited value.
Patrick Oliver: "They don't even think about body position or of catching a fall and instead leave it to the gear to do the job. I have found the belay is much stronger by relying on oneself first, and secondarily the gear -- as a general rule."
For years now, I've been 'preaching' about the art and craft of "stancing" to a largely deaf digital ether. I consider stancing, and surveying for the various body locks one can apply, and shift through in the process of a belay, to be a key element of selecting where to belay. I, too, consider an anchor as simply a backup to my belay in all circumstance where an adequate stance can be established. Where a dubious stance is all that's offered I still employ it as a 'contribution' to the overall anchoring chain even if it that stance might ultimately fail.
Patrick Oliver: "still don't use a belay device and prefer a hip belay, with a carabiner to clip the leader's rope on my swami on the opposite side of the brake hand. Probably sounds archaic, but it has always worked."
This is how we always belayed as well and it took a decade of deep suspicion to 'trust' any form of belay device. I've held many hundreds of solid lead falls, including several directly onto my belay, with this technique. It is as safe and effective as any belay device touted in today's 'modern' world. I still hip belay for a good portion of my belays - particularly anytime a partner is going to be moving fast as it's simply more responsive than any device.
Karl Baba: "It's true in the modern age that many climbers are more willing to fall long and hard and this just won't wash anymore. I took a factor two fall past my belayer using a hip belay BITD on the second pitch of Mud Flats and it burned his hand."
Bunk! We actively despised the "leader must not fall" mentality and took plenty of long lead dives on our hip belays (roofs and steep are just that way). If your second got burned, he either wasn't using a directional biner as Patrick describes, he didn't lockoff effectively [by diving the brake hand between his thighs], had a bad/no stance, or he simply wasn't experienced hip-belaying. I've never been burned in similar situations (and in fact, to some extent, think gloves could tend to mask bad practices; I don't use them anyway).
Patrick Oliver: "It sometimes amazes me when I climb with people who have all the newest gear and gadgetry who can't comprehend how I could survive using the system I do."
Patrick, your combined comments are breath of fresh air. Whether this conversation were taking place in '68, '78, '88, '98, or '08 - the issues are the same. And I simply think that even back in the day only a certain percentage of climbers really "got it" relative to the technical, or craft, side of climbing let alone the perceptual and sensory awarenesses necessary to raise it to 'art'. The combination of mindset, body-awareness, stancing, technique, alertness, and active attention to and adjustment of every detail in the overall 'system' is the heart of what raises belaying to a craft and even art in my eyes.
That doesn't even include the focus necessary to learn a leader's habits such that you can anticipate them via 'listening on the line' by maintaining enough subtle tension to have a shot at actively understanding what an out-of-sight leader is doing on a second-by-second basis.
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healyje
Trad climber
Portland, Oregon
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Nov 27, 2008 - 05:47pm PT
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As to the actual question of clipping the anchor - new [well] bolted anchors, sure. Trad anchors? Never. I'd rather catch the fall directly on my belay. When I set a trad anchor it is always woven into a performant whole; in almost all cases, clipping a piece of it would, by definition, disrupt all the intentions and design of that performant whole 'anchor system'.
I'd rather worry about catching the fall then have to worry about my anchor failing.
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Mighty Hiker
Social climber
Vancouver, B.C.
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Nov 27, 2008 - 06:11pm PT
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One way for people to learn how important good belay technique, and solid belays, are:
(Also posted elsewhere.)
Or they can learn from reading "Belaying the Leader". As long as they don't get any odd ideas about climbing being safe. If they learn how to do a hip belay, and a carabiner brake rappel, that would be a GOOD THING. Learning how to use a slide rule optional, though.
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Peter Haan
Trad climber
San Francisco, CA
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Nov 27, 2008 - 06:13pm PT
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Well perhaps we don't actually differ, you and I, Healje. If I had a clearly bad anchor assembly and no good piece to start off leading with separate from the anchor array, besides this being an advanced situation and the team would be on red alert of course, I would not clip into the anchors either (since you magnify the fall force if you do and you also introduce usually some suddenly developing slack if the fall pulls the anchors) and would attempt to obtain the best possible stance as the first order and would have to hope that taking a fall on the belay device directly would be actually better than loading the anchor array. But this would be very unusual situation and obviously very dangerous (as in you don't even want to rely on your anchors).
And in 45 years of climbing, I have only been in this situation a ten or twenty times. And I would also add that when the anchors are that bad sometimes we move the bad belay up (inchworm or simulclimb style) after the second has reached an appropriate point to do so and has generated enough new lead rope to allow further progress, since apparently the lead rope just is not long enough for the situation.
If I had great anchors I would clip FROM the master point (not some part of the anchor array) but with a separate carabiner for a first piece if the direction works and would immediately attempt to get another piece asap in the next few feet. This is the most common belay situation for my friends and i.
Taking a fall directly on the belayer and his device with nothing intervening is a very nasty situation, very violent and I would imagine that most people would find that they simply could not stop a fullsized climber falling 15-20 feet even, that they would lose their stance completely and be injured along with the leader, if not killed. But yeah, clipping the anchors in this situation would have meant that all possibility of survival has been precluded in a big fall....RR used to say, "we don't use a rope so that both of us would die".
But yeah, if the anchors are not competent don't clip them. The discussion mostly is revolving around what kind of anchors we are all thinking about.
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George R
climber
The Gray Area
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Nov 27, 2008 - 09:29pm PT
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My perspective on rgold's initial question:
As with most questions, the best answer is "It depends".
If I'm confident the belay anchor can withstand the increased force involved in being used as the first point of protection, then I will be comfortable with clipping the lead rope through the anchor. Otherwise not.
My bias is against clipping the anchor because:
1) Unprotected (factor 2) leader falls are survivable. Unpleasant no doubt, but survivable, IF the belay anchor holds.
2) Belay anchor failure will almost certainly result in death for everyone attached to that anchor.
3) Clipping the lead rope through the anchor increases the likelihood of anchor failure, by increasing the force on the anchor.
So, I don't routinely do it, but I will consider it if I feel the anchor clears the bar of being strong enough to hold the additional force.
Considering Largo's question: "...when should the leader run the lead rope through the anchor, and when should he avoid doing so?" Here's my take on it:
Scenario 1) the anchor is sh#t and there is no chance to place a "Jesus Nut" (first piece of pro off the belay) for at least 20"
NO. If I'm not completely confident the anchor will hold the increased force, I would not clip the rope to the anchor. This is the most difficult and scary case. How to deal with the situation, (move belay, bail off, etc.) will depend on the other elements of the situation.
Scenario 2) the anchor is stout and there is no chance to place a "Jesus Nut" (first piece off pro of the belay) for at least 20"
YES. This is the one case in which I would clip the anchor.
Scenario 3) the anchor is sh#t and the leader can set a sound Jesus Nut straight off the belay
NO. Same as Scenario 1 plus if you can get sound protection right off, there's no point to clipping the belay anchor anyway.
Scenario 4) The anchor is stout and a Jesus nut is available right off the belay
NO. Even though the anchor is stout, there's no need to clip the anchor if you can get good pro immediately.
I believe that a lot of climbers do not understand that using the belay anchor as the leader's first protection point will almost certainly increase the force it may have to withstand. I hope this discussion contributes to correcting that. Thanks to all for a great discussion!
G
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martygarrison
Trad climber
The Great North these days......
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Nov 27, 2008 - 09:36pm PT
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I am not going to get into the physics of this debate. My rule of thumb has always been to never have the leader clip the anchor as pro. I held a complete factor two on na wall pitch three where my leader pulled everything and went sailing past me on to my two inch swamie, hip belayed. I then had to hold him as he jugged back up to the belay. I can attest had I clipped him through the anchors, quarter inch bolt and a couple of pins, we would both be dead.
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WBraun
climber
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Nov 27, 2008 - 10:28pm PT
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Who really is the anchor .....
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Largo
Sport climber
Venice, Ca
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Nov 27, 2008 - 11:10pm PT
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Thanks, George.
Marty, that NA falls sounds horrifying. Good catch, dood!
We were always afraid of this kind of fall, especially when we were doing new face climbs at Tahquitz and Suicide and on Middle Cathedral (early 70s) - all this, using a hip belay. The fear was that if, say, your left hand was the brake hand and the leader fell past you on your right, the rope (if not clipped through the anchor) would peel the belay off your right hip and out of your guide (right) hand and then there would be no way to hold on. So we started clipping a biner into our swami and running the rope (opposite the brake hand) through that so as not to have the rope torn around our back should the leader fall onto the belay. Eventually we started clipping the leader into the anchor without knowing jack about force multiplication or the pulley effect or any such thing. It really is a wonder nobody ever fell killed us all on routes like Greasy but Groovy, et al, which featured huge (like 75 feet) runouts right off the belay.
Don't fall . . .
JL
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healyje
Trad climber
Portland, Oregon
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Nov 27, 2008 - 11:24pm PT
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Largo: "So we started clipping a biner into our swami and running the rope (opposite the brake hand) through that so as not to have the rope torn around our back should the leader fall onto the belay. Eventually we started clipping the leader into the anchor without knowing jack about force multiplication or the pulley effect or any such thing."
Making the biner 'captive' in the front is the reason we switched from swamis to 1" tied harnesses.
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Gilwad
climber
Frozen In Somewhere
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Nov 28, 2008 - 12:00am PT
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The reason I don't generally clip the top piece in an anchor is that the belayer's hand often gets pounded into the carabiner so hard that the force can break bones, destroy skin or otherwise cause such extreme distress that he or she will let go with both hands. The belayer also gets pounded into the wall very, very hard, and the instinctual reaction is to leg to and protect one's face. For these reasons alone I'd rather not have the top piece in an anchor clipped. I have caught a factor two on a hip belay (first real leader fall I ever caught, aid climbing in a cave), catching one with modern belay device should be relatively OK for most people. And then there's the physics of it all too... There are situations where clipping the top piece makes sense, but they are relatively rare. I can't think of the last time I clipped the top piece off an anchor.
The falling rock picture brought back memories of learning to belay. Before you could belay in my school program (the White Mountain School) you had to catch a falling log on a hip belay. It was set up so you were jerked into the air, spun upside down and left dangling through several bounces. More of that sort of training would be good, that training is still ingrained my head. Thanks Fitz.
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Karl Baba
Trad climber
Yosemite, Ca
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Nov 28, 2008 - 01:22am PT
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General idea:
Once experienced climbers have a familiarity and comfort with the gear and systems, they can adjust their strategy to the tast, anchor, rock and problem at hand.
Still, some rules of thumb and procedures are well advised for those to don't grasp everything. Of course, even experienced climbers have been known not to understand the dangers of things like "the american triangle" but somehow, most accident for the seasoned climber don't seem to boil down to issues like we are discussing.
I'd use a different term than "Jesus nut" since I think it's preferable to have an omnidirectional piece like a cam as a first piece of pro. Nuts are prone up an upward zipper when the highest piece of pro has the rope weighted through it and the belay is back or to the side of the climbing.
peace
Karl
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G_Gnome
Trad climber
In the mountains... somewhere...
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Nov 28, 2008 - 01:51am PT
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I've been pulled up the wall 10 feet ripping evulsions on the backs of my fingers, I've had my hand pulled into the directional biner (no broken bones), I've caught big falls off the belay device. I would rather get pulled into a biner. I will never let go and I am in control. Sorry, but a pull straight onto the belay device is my least favorite and most unsafe way to catch. Now, if the anchor really is that bad then I might make other choices, but in any other situation (like almost every time) I WILL use a directional.
So then, if the anchor can't really hold a big fall then do what you feel is safest (retreat?), otherwise I will used a directional.
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Todd Eastman
climber
Bellingham, WA
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Nov 28, 2008 - 02:05am PT
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"You are on belay, but don't fall!"
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Mighty Hiker
Social climber
Vancouver, B.C.
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Nov 28, 2008 - 02:19am PT
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As I believe Oli said in Swaramandal: "Don't fall or we'll both go!" Quoting one of his early partners.
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JohnRoe
Trad climber
State College, PA
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Nov 28, 2008 - 11:46am PT
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Geek stuff:
I put the fall model I used for the previous calculations up on my website as an Excel spreadsheet
here.
You can download it and play around with the parameters (rope out, mass of climbers, etc). The figures in my previous post were too large because of the assumed 40kN rope modulus. I found a more plausible figure of 11.2kN in
this thread from 2006.
The calculations indicate that with 80kg climbers, the belayer 1m below the anchor, then what rgold calls the "breakeven" point occurs with 1.5m rope out if the belayer is statically anchored for upward pull, and with 2.2m rope out if the belayer is hanging. In other words, beyond that point a factor-2 fall direct on the belayer puts less force on the anchor than clipping the anchor as the first piece.
Anti-geek stuff: Mathematical models are only as good as their assumptions (garbage in, garbage out - as in valuing mortgage securities...). To test those assumptions, one needs to be experienced with the situation being modeled, not simply to be a mathematician. There is an awesome amount of experience on this thread.
One assumption which is pretty unrealistic is that the clip is made to the power point of the anchor. Usually the leader clips the topmost piece, or one bolt if the anchor is bolted. So the (usually higher) force in the "clip" scenario is being applied to the anchor in a very un-equalized way.
JohnR
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JohnRoe
Trad climber
State College, PA
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Nov 28, 2008 - 01:07pm PT
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Karl wrote
"John, if you could run one more scenario, Factor two fall when the belayer is belaying with a gri-gri directly off the powerpoint, but is hanging on the anchor. (possible aid climb scenario)"
Although the set-up is different, physically this is equivalent to "Scenario 1" in my list so the numbers should be the same.
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chainsaw
Trad climber
CA
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Nov 28, 2008 - 04:31pm PT
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Why not just be smart and belay with a Gri-Gri? If you want, you can rig it to the anchor and it is not a pulley. Just be smart and throw in a Bomber directional. I prefer to belay the leader off my harness. Holding a struggling climber who is actually falling onto the belay is a bitch with an ATC. Just holding their weight gets old. If you work anything hard, ATC is exhausting. Fatigue is not good. Yeah, sometimes you can give a nice dyno off the ATC but that is a judgment call and skill not to be expected from beginners. I believe the Reverso can sub for the Gri-Gri if you don't like bulk and weight. Don't ask me to set this up though. I don't own a reverso.
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healyje
Trad climber
Portland, Oregon
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Nov 28, 2008 - 04:46pm PT
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"Chainsaw: Why not just be smart and belay with a Gri-Gri?"
Too many reasons to go into here as it's a fairly off topic and another discussion altogether. Suffice it to say, likely a bunch of us here just don't use grigris. I used for soloing before I got an Edelrid Eddy, but didn't and don't use either for belaying.
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WBraun
climber
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Nov 28, 2008 - 05:42pm PT
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That's all I've ever used for a belay device since it first came out.
A Gri-Gri.
I don't know why everyone is so scared of this device.
I works perfect. I hate all those stupid ATC type units. Blah!
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healyje
Trad climber
Portland, Oregon
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Nov 28, 2008 - 06:48pm PT
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Well, Werner, we simply disagree, I personally don't care for grigris at all and I do own two of them...
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tito
climber
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Nov 29, 2008 - 12:07am PT
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JL,
Today, I was looking over the test results in your latest Climbing Anchors book, and I have to say, the way you present the results of the tests to the reader makes them difficult to evaluate. You state the difference in force that each leg of the anchor felt after subjecting the anchor to a factor 1 fall, e.g. the left side felt 1 kN less than the right side. Is that significant? You never say what the total force was on the anchor, so it is difficult to interpret those numbers. What I want to know as a reader is what percentage of force went to each leg, e.g. the left side felt 60% of the force and the right side felt 40% of the force, so that I can determine how good the equalization was.
It would also be nice to know the actual force felt by each arm, so that we could see how much of the force friction dissipated. For instance, if one leg of an equalette felt 4 kN and the other felt 3 kN, then we would know that 1kN was dissipated by friction--which would give us great insight into how big a role friction actually plays when a rope runs over a biner at the power point.
Finally, the graph on p. 189, which purports to show the results of your tests on each type of anchor using some bizarre stick-connected-to-bar graphs, has no accompanying explanation. What do the shaded rectangles and the numerous vertical lines mean? I am pretty sure I know what some of the lines mean, but for others I have no idea.
Therefore:
1) If you could post answers to any of those questions here, I would be most grateful, and I will pencil them into the margin of my book.
2) I suggest you present the results of the raw data in a more meaningful way in your new book.
Sorry for going off topic, but I thought JL would be most likely to see these comments here.
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Sir loin of leisure...
Trad climber
X
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Nov 29, 2008 - 12:08am PT
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ALL BOW BEFORE THE SAGE WISDOM OF WERNER....gri gri,s rule...
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Karl Baba
Trad climber
Yosemite, Ca
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Nov 29, 2008 - 12:38am PT
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John wrote
"One assumption which is pretty unrealistic is that the clip is made to the power point of the anchor. Usually the leader clips the topmost piece, or one bolt if the anchor is bolted. So the (usually higher) force in the "clip" scenario is being applied to the anchor in a very un-equalized way.
JohnR"
Here's my take, if the leader clips the topmost piece, or one bolt if the anchor is bolted, it's usually because the anchor is bomber. If the anchor is not bomber, the leader is more likely to clip the powerpoint (or just say his prayers) Of course the leader will try to get a good piece in asap but if a good piece was very close, why is the belayer using a crappy anchor? (out of rope?)
There's always so many factors.
as for those scenarios, I can see how your scenario #1 john may seem the same to my questioned scenario but I bet we'd be shocked to see how different the forces on the anchor would be between falling right on a gri-gri fastened to the anchor and falling on the belayer. Human meat is like a big screamer. We have all kinds of give in us, and of course, there is the harness and rope tie in to consider.
PEace
Karl
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Largo
Sport climber
Venice, Ca
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Nov 29, 2008 - 12:46am PT
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The test results, figures and graphs were worked up by two nationally recognized statistics profs, Larry Hamilton and Callie Rennisson. The whole point of the thing was not be a raw data source but for two experts to review the data, crunch the numbers and for the book to present provisional rules of thumb. Maybe Wottles can provide you with the actual figures if you could provide him good enough reason to dig them up.
JL
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tito
climber
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Nov 29, 2008 - 01:01am PT
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> The whole point of the thing was not be a raw data source but ... for
> the book to present provisional rules of thumb.
Then it doesn't make much sense to state what the actual difference in forces between the two legs was. All most readers care about is how well the tested anchors distributed the forces. Was it 60%-40%? 70%-30%? When you state that the difference in force between the two legs of a tested anchor was 2 kN, how is the reader to know whether that is closer to 50%-50% or 70%-30%?
That is sort of like a knot book saying that a knot weakens the cord by 3 kN instead of 25%(which is what they actually do).
My post gives you some reader feedback for the new edition. You can take it or leave it.
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nick d
Trad climber
nm
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Nov 29, 2008 - 01:26am PT
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Who cares what Tito thinks, I'm waiting for Jermaine to chime in.
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JohnRoe
Trad climber
State College, PA
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Nov 29, 2008 - 08:09am PT
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Karl wrote
"I bet we'd be shocked to see how different the forces on the anchor would be between falling right on a gri-gri fastened to the anchor and falling on the belayer. Human meat is like a big screamer. We have all kinds of give in us, and of course, there is the harness and rope tie in to consider."
I agree. Another unrealistic thing about these models is to see the climbers as point masses. They are not even rigid bodies, let alone point masses, at the scale of the effects that we're considering. We are also neglecting rope slippage (dynamic belay) if an ATC type device is used.
I bet though that, even if one incorporated all these effects into a more realistic model, the overall pattern of the numbers would still be the same... after a comparatively short distance, clipping the anchor loads it more in a fall than not clipping. (But the belayer is loaded much more in the factor 2 situation.)
Peace
JohnR
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sibylle
Trad climber
On the road again!
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Nov 29, 2008 - 10:21am PT
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Someone said:
"Personally I would never consider clipping a belay device directly to a fixed anchor."
and jstan said:
"Amen, brother! In general I consider this, a commercial activity at best, and one that breeds entirely the wrong long-term 'sensibilities'; at worst, I think it's slovenly in a way that divorces you from any number of sensory pathways to knowing what is going on with your partner. I only even redirect under rare circumstances."
I've climbed in Europe. Almost all European guides and climbers clip the belay device directly into the anchor and were shocked to see me clip my device to my harness. One of them said,
"Do you still do that? Haven't you learned modern techniques?"
I've been yelled at by climbers who worked as guides in Europe for belaying incorrectly when I clip the device to my harness.
So are most Europeans belaying incorrectly? Or are Americans? Or is it a mattter of style, taste, and judgment?
I clip the device to a GOOD anchor when belaying a heavy second. Once recently, I could not easily do so and had to hold someone who weighed 60 or 70 pounds more than me on my harness for a long while and could hardly breathe.
What I mentioned earlier - what if a climber that weighs 100 to 120 pounds belays a climber who weighs 180 to 220 pounds? Have any of you caught a leader who weighed almost one hundred pounds more than you?
I have. It sucks no matter how you belay them.
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Karl Baba
Trad climber
Yosemite, Ca
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Nov 29, 2008 - 12:35pm PT
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It's not just europe. 10 years ago I took the YMS clinic for prospective guides and the AMGA certified leader (actually it president at one time) taught that his favorite method of bringing up the second was a gri-gri on the powerpoint of a cordalette anchor.
I tried it out and found it to be way better than anything I'd done before. You still get plenty of "feel" for the climber (like fishing) if you use your hands on both sides of the device when bringing up the second. It's so easy you get a better cool down at the belay and makes it easy to manage the rope for the next lead.
Don't knock it if you ain't tried it. The AMGA and the euro scene are not a bunch of reckless dummies.
Peace
Karl
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TradIsGood
Chalkless climber
the Gunks end of the country
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Nov 29, 2008 - 12:57pm PT
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There is a difference between bringing up a second off the power point and catching a fall on the power point.
With the GriGri, or any autolocking device, the rope does not slip. Effectively the coefficient of friction is infinite. So the load on the power point is just the weight of the second. If the second falls, the fall factor is (or should be) much lower than one. Thus the load on the anchor is minimal.
If one were to belay a leader off the power point with such a device, it would reduce the load similarly, since there is no "pulley" in this system. I have not seen this done in practice. I guess though, it might serve to limit the anchor load to a factor 2. I am not familiar enough with the spec's of the gri-gri, though to comment with any conviction on that.
I have used the reverso to belay off the power point when I am not concerned that I might have to lower the second. When that is a concern I often will belay with a Munter hitch. (This has a slightly higher load, since some tension is required on the tail.)
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jstan
climber
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Nov 29, 2008 - 01:14pm PT
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Sibylle:
The two attributions above are reversed.
If someone criticizes another's technique but cannot give a persuasive argument you know right away what to do. To my mind belaying directly off an anchor with a device fails on two counts. First it materially increases shock on the entire system. A system you personally did not build so you do not have detailed knowledge of its shortcomings. Secondly if the anchor does fail you may entirely lose the belay. I have never belayed off a seat harness. If I were using a seat harness I would probably belay off the waist loop since that is what I know. If both the tie-in and the belay both come off the crotch loop you better have a loop of 1" tubular directly backing that up to your waist loop. Being retarded I consider even the waist loop on a harness to be too complicated to merit complete trust. Best thing to do would be to use a swami under the harness if you really need a harness and tie them together as a backup for each other.
Things are never what they seem. Here I need only refer to T.M. Herbert's story of the waist loop that had a piece of masking tape on it.
The problem you raise about climbers of very different weights has not gotten the attention it deserves. On an extended climb I would be inclined to drag along an extra rope when this is a factor. Might turn out to be necessary. And when you can see a worrisome scenario coming up it always helps to let the leader know they have a problem with which to deal.
Long time ago I accidently found myself above one of those ceilings in Eldorado belaying about a 180# French climber on doubled nines. Somehow he thought one of the ropes was impeding him so he threw one off leaving me holding him on a single nine and looking at an 80 foot lower in free space - over my gym shorts. Dead weight with no friction in the system is very unforgiving. Fortunately while he was occupied throwing off the rope I had been busily building some friction into the belay.
This kind of thing is completely missing from indoor climbing by the numbers. Frankly I don't know how a person can stay interested in that stuff. But there are a lot of things I don't know.
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JohnRoe
Trad climber
State College, PA
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Nov 29, 2008 - 01:37pm PT
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Question for rgold or another modeler out there:
After one of Karl's posts above, I got interested in the question of what happens in a factor 2 fall when the belayer is connected to the anchor by a dynamic tether (the climbing rope) rather than statically.
The conventional wisdom is that the dynamic tether will reduce the peak load on the system. That is certainly what I expected to find.
But the model shows something quite different: the dynamic tether increases the peak anchor load, from 7.6kN to 10.1kN in the standard example (4m rope out, 1m tether).
What happens is that the fall gets the belayer moving as well as the leader, and the anchor then has to stop both of them!
OK, questions: Has anyone else tried to model this effect? Do you believe that it is real?
If it is, then under most circumstances the extra force it produces on the anchor in the factor 2 situation (scenario 1) is pretty close to the "pulley effect" force in scenario 2 (anchor clipped, belayer static). This leaves scenario 3 (anchor clipped, belayer free to be pulled upwards) as the theoretical winner.
Standard anti-geek disclaimers apply.
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rgold
Trad climber
Poughkeepsie, NY
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Topic Author's Reply - Nov 29, 2008 - 01:42pm PT
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Sibylle (and others),
The use of anchors in Europe for direct belays is, to some extend, a byproduct of their more extensive array of bolted stances, is it not?
I don't think it will be long before the European example and the pressures exerted in this country by climbers less and less competent in the trad arts and more and more enamored of modern conveniences will lead to very extensive bolting of trad anchors here too. It has certainly already started, and when it becomes more or less universal, this discussion will be moot.
In the meantime, here, for whatever it is worth, is my approach to the anchor-clipping dilemmas. YMMV.
I'd like to begin with the assumption that the anchor is NOT "bombproof." The definition of a bombproof anchor is you can do whatever you want. Let's talk about the real world, not about the very occasional crap anchor that we also sometimes have to accept, but about the greyer spectrum of anchors that are probably ok but, if we are honest with ourselves, are not "bombproof." I must say that I mistrust the judgement of people, regardless of their experience, who insist they don't have to belay off such grey cases say, 5-10% of the time. Every anchor bombproof, pitch after pitch, year after year? I don't mean to be offensive, but I'd say, no way. Neither common sense nor statistics suggest this could be true.
If you do not accept that some of the time you are belaying off anchors that may not be bombproof, read no further. Your problems are over, one way or another. Go ahead an clip whatever. But if you are prepared to admit this particular view of reality, then I think you'll also agree, perhaps after some quiet reflection on how many of your anchors have been put to any kind of severe test, that you may not really be so good at judging which of those grey cases are worse and which are better. After fifty years of placing anchors, from soft iron through cams, tricams, brassies, and ball nuts, this is at least my conclusion for myself. And the only person I have ever met who I think might be a whole lot better than me is John Stannard, because he is the only person I know of personally who has placed gear, made an evaluation, and then tested the placement to see how his judgements corresponded to reality. Anyone else like that out there, I defer to your superior judgement and your wisdom in acquiring it.
So, if you haven't stopped reading in disgust or outrage, then you are in a position to admit that a certain fraction, hopefully quite small, of your anchors may not be all that great, and, sadly, that you may not be omnsicient when it comes to perceiving which ones are better and which worse. It gives me absolutely no pleasure to support this position by noting that in virtually all the cases I have heard about in which parties have been swept from the cliff because of anchor failure, the climbers involved have been experienced, and their experience was not good enough.
All of this leads me to the basic view that one should, as much as possible, arrange to load at least those grey-spectrum anchors as little as possible, applying a broad definition of "greyness" in view of our fallibility as judges of anchor integrity where huge forces are involved. The result is, as practical matter, I rarely clip any portion of a trad anchor when leading.
However, I do, in a certain sense, believe in belaying off the anchor. Many of us here have caught humongous falls with hip belays, and we know that with the right approach and appropriate levels of attention, it is an unpleasant but not catastrophic experience. But anyone with an appreciation for the possible forces, and anyone who as experienced them first-hand, cannot be utterly sanguine about the potential for belayer injury and/or loss of control. I think the anchor needs to play a role, and not as an afterthought after the belayer has collapsed.
So here's what I do, for upper and leader belays. I use a modified harness belay that is, in practice, only partially on the harness. I always tie into the anchor with the rope---what I am about to describe would be compromised if I used low-stretch sling or cord. My tie-in is typically snug, with at most a very small amount of slack; "play" would be a better word. Doing this fast and right requires clove hitches, in my opinion. I am not worried about their integrity.
Now here's the critical detail: I clip my belay device into both the harness belay loop AND the tie-in knot loop of my anchor rope. This means that loads to the belay device are transmitted to the anchor directly, rather than loading up the belayer's harness first. However, since the anchor rope stretches, the belayer has some opportunity, in the case of the high loads of a factor-two fall, to resist with appropriate stancing, to use Joe's term, and thereby reduce to some extent the total load to the anchor. Since the connection is direct, the increase in load guaranteed (sorry, Karl) by the pulley effect after the break-even point is not a consideration.
This is what I do most of the time, because I think it will result in the lowest anchor loads consistent with belayer safety. Whether, in reality, my anchors need this tender consideration is not much of a factor in my decision, because I do not pretend to know for sure.
When this system is used for upper belays, the stretch in the anchor rope is minimal and you basically have a belay off the anchor. There is absolutely no discomfort in holding a fallen second; I've done this, for example, while they prussicked up five or six feet to clear an overang. There's no pain because they are hanging on the anchor, not on you.
But, unlike the modern direct belay off the anchor, this one has some extra load-reducing capability if your communications screw up, your second accumulates some slack and then takes a leader fall. Because then, the stretch in the anchor tie-in and the connection to the harness gives the belayer the opportunity to resist, given appropriate stancing.
It should be clear that there is nothing time-consuming or at all complicated about this; there is in fact no difference in set-up time from the usual approaches. It does mean, for upper belays, that the belayer has to be actively engaged in the belaying process, rather than eating snacks, applying sunscreen, snapping photos using both hands, practicing tai-chi, and other lapses of attention now viewed as both acceptable and desirable because of locking anchor belays.
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nick d
Trad climber
nm
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Nov 29, 2008 - 02:03pm PT
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John R., I think there is a mistake in your model. If there is an increase in the load on the anchor it should only be the weight of the belayer hanging on it. Your numbers sound like the belayer is falling with the leader and both their weights are impacting the anchor. This should not be the case.
I don't see any way that a dynamic rope can increase the load on the anchor. Am I seeing it wrong?
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rgold
Trad climber
Poughkeepsie, NY
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Topic Author's Reply - Nov 29, 2008 - 02:08pm PT
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John, an excellent point. I have thought about it but hadn't got around to the modelling. It does seem possible that a falling belayer would make clipping the anchor at least equivalent to the factor-2 choice in terms of anchor load. One of the advantages and reasons for the tie-in method I just described above is that it passes the load directly to the anchor rather than through the belayer, and so either eliminates or at least mitigates the effect you suggest, depending on how much the belayer tie-in stretches.
I believe, as much as possible, in the belayer adopting good old-fashioned braced stances, and suspect that this can further mitigate the peak loading effects of a pair of coupled harmonic oscillators. I'm pretty sure bracng played a significant role in the one factor-two fall I've had to hold; I was well-braced yet still driven to my knees by the impact. My quads were sore as hell the next day, indicating a significant level of resistance. The anchor, by the way, consisted of a single piece, and as you can tell, it held.
By the way, I think the anchor loading results of connecting the belayer to the anchor with low-stretch slings or cord would be much more substantial; that stuff has significantly higher "modulus."
I've had extensive experience, years ago, catching practice high fall-factor falls with weights. That experience convinces me that, in most circumstances, the belayer will be pulled violently up to the clipped anchor if they are not anchored down, with results no more predictable than what may happen to a belayer stressed by a factor-two fall. But the peak loading shouldn't occur until the belayer has hit the anchor, at which point there is no longer any pulley effect.
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Karl Baba
Trad climber
Yosemite, Ca
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Nov 29, 2008 - 02:11pm PT
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RGold wrote
"Now here's the critical detail: I clip my belay device into both the harness belay loop AND the tie-in knot loop of my anchor rope. This means that loads to the belay device are transmitted to the anchor directly, rather than loading up the belayer's harness first. However, since the anchor rope stretches, the belayer has some opportunity, in the case of the high loads of a factor-two fall, to resist with appropriate stancing, to use Joe's term, and thereby reduce to some extent the total load to the anchor. Since the connection is direct, the increase in load guaranteed (sorry, Karl) by the pulley effect after the break-even point is not a consideration."
You might want to review Jroe's last post. It seems that your technique is the worst of both worlds to some degree. In a big factor two fall, the anchor is going to have to hold you and the leader, and you still have the disadvantage of being pulled down.
In reality, I'm sure it's likely that some mitigating factors will ameliorate this issue but it does for the other scenarios as well, which brings me back to my practicality based view that whatever helps you catch the leader in any scenario without risking losing the belay is safer than worrying about the whole anchor pulling (since that is amazingly rare where I climb)
Now I do want to note, since some have missed it, that I only belay directly off the anchor using a gri-gri, to bring up the second. I've aid climbed enough to have years and years of experience to know my anchors are always going to be good enough for those forces (there may be a handful of times I didn't do it because of a sub-optimal anchor)
A not-insignificant advantage of the gri-gri belay of the second is this. If there is a spray of rockfall from above (and this happens!) It would be possible for the belayer to fall and the belayer to get hit by rocks at the same time. With the gri-gri belay, the second still gets caught. With a regular device or hip belay, he could be dropped easily. This scenario is probably as likely as a seemingly good anchor failing in some of the discussions we've had above.
on another note, in lead situations, where I'm belaying off my harness.
To me, a real safety factor is putting a little or a lot of my weight in my harness by somewhat hanging on the anchor. That way, if the leader falls, I'm not knocked off my feet as easily or slammed into the wall, where I might let go!
peace
Karl
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JohnRoe
Trad climber
State College, PA
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Nov 29, 2008 - 02:13pm PT
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nickd
Here's what the model says: Think about the moment when the falling leader comes taut on the rope. The belayer (hanging) has to develop the force to stop the leader. This force is transmitted to the anchor through the belay tether. The force in the belay tether makes it stretch (because it is assumed to be dynamic). So, the belayer starts moving downwards. Now the belayer and the leader are both moving down and they both have to be stopped...
See "systems of second order ordinary differential equations" in a calculus text...
The question is whether in reality there is so much damping in the system that this is just irrelevant theorizing.
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Karl Baba
Trad climber
Yosemite, Ca
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Nov 29, 2008 - 02:18pm PT
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THere are so many way of seeing this and so many factors involved, I just think it would be a great magazine article or a serious contribution post if some of you geeks and those with access to testing devices (maybe get sponsored by gear makers) set up some scenarios at a crag and tested various setups and got real world numbers.
Seeing how theory and practice match up in climbing would give us a baseline to see how useful the theory is
Peace
Karl
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nick d
Trad climber
nm
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Nov 29, 2008 - 02:27pm PT
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John R., I guess my question is how far could the belayer really go? I've been jerked a couple of times over the years while standing at an awkward stance, but thats a distance of maybe ten inches, a foot at most? I think I probably absorbed some of the energy before I came tight to the anchors.
I'm not a math guy, I'm just relating this to my personal experiences, so I might be full of it! I just don't see how I could have added much more than my bodyweight to the system, and in most cases I would have already been semi-hanging on the anchors before the fall.
I still see my contribution as a shock absorber more than a huge increase in the ultimate load.
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JohnRoe
Trad climber
State College, PA
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Nov 29, 2008 - 02:42pm PT
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nickd wrote
"John R., I guess my question is how far could the belayer really go?"
Yes, this is the key question. Think about it this way. The force needed to stop a factor 2 freefall is about 7kN. The rope modulus is about 11kN. So, the tether could stretch by well over 50% under the kind of forces that are going to be developed in a factor 2 situation. (This is just a ballpark figure of course.) Since this stretch happens in a few hundred milliseconds the belayer is moving surprisingly fast - in my model the belayer ends up moving at 4 m/s. Not as impressive as the 12 m/s the leader achieves when he hits the end of the rope after the factor 2, but enough to require quite some retarding force.
Of course, the belayer's stance can mitigate some of this.
JohnR
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nick d
Trad climber
nm
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Nov 29, 2008 - 03:05pm PT
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John R., I guess I kind of got away from my original point, that being the forces have to be lower with a dynamic tether rather than a static one. I still believe that.
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rgold
Trad climber
Poughkeepsie, NY
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Topic Author's Reply - Nov 29, 2008 - 03:43pm PT
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Karl Baba wrote: "It seems that your technique is the worst of both worlds to some degree. In a big factor two fall, the anchor is going to have to hold you and the leader, and you still have the disadvantage of being pulled down."
Karl, here's the situation: The maximum elongation you are going to see in a dynamic rope is perhaps 38% (according to the Beal site---Beal ropes are typically among the stretchiest.) That's after the first fall under carefully controlled conditions; in the field with a used rope you'd expect a bit less.
Sticking with 38% and assuming a 3 foot tie-in, the biggest elongation you might possibly see is about 14 inches. So the belayer, who is not taking the direct load of the fall on his or her harness, will be forced, in the worst-case scenario, to do a deep-knee bend as the load is absorbed by the anchor, even if the belayer is hanging in slings. This is very far from the belayer being another falling object in John's calculations; it is conceivable if not likely that the belayer's presence would have no effect at all on the peak load, and it is also conceivable that the application of belayer quadricep power could effect a minor reduction.
By the way, as a reality check, this is pretty much exactly what happened to me on the factor-two fall I caught.
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GOclimb
Trad climber
Boston, MA
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Nov 29, 2008 - 03:48pm PT
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Rgold said: "John Stannard... is the only person I know of personally who has placed gear, made an evaluation, and then tested the placement to see how his judgements corresponded to reality."
For what little it is worth, I have also done the above.
My takeaway from the experiment was two things:
1 - I personally developed a better eye at evaluating the placements (within the narrow range of types of rock and types of gear I used). This has some value to me personally as a climber, but no relevance to this discussion.
2 - The realization that in small to mid sized cam placements (up to around 1 inch) the conventional wisdom about which placements are "bomber" is so naive as to be effectively wrong.
To elaborate on point 2: What I found was that very minor features of the placement (nearly impossible to determine without a trained eye and plenty of time to fiddle) can mean the difference between a piece ripping out versus holding, in relatively small falls (on the order of FF = .2 - .5) Factors like a little grit in the crack, or the relation of one lobe on versus behind a crystal.
Basically, the only "bomber" small to medium-small cam placement is one behind a constriction in good rock. All others take a very very careful eye to determine the likelihood of holding. And honestly, it's so variable depending on the quality of the rock in the crack, that you're better off just assuming that if it's not behind a constriction of some type that it is *not* bomber.
GO
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rgold
Trad climber
Poughkeepsie, NY
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Topic Author's Reply - Nov 29, 2008 - 04:34pm PT
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Gabe, I salute your wisdom and industry and welcome your observations.
I've always assumed that cams 1" and less belonged to the grey part of the spectrum I described earlier. Within the last year I was forced to use such an anchor, four sub-1" cams in a horizontal sandstone crack. Each one was "good," but I was not happy. It was clear that the next pitch wouldn't have any protection for a long while, and the rock that we were on was not perfect. I had plenty of confidence in my companion, but still thought a factor two fall onto this set-up was a possibility.
No way in hell would I have clipped that anchor. I equalized the placements in pairs with sliding X's and clipped each one with one strand of our double climbing rope. Fancier set-ups would have resulted in too long an anchor and would have forced me to hang from it, and I wanted to get braced as much as possible to spare the anchor. The belay was in a kind of sloping dish and such bracing as was possible was cramped and not very effective, but I judged it better than nothing.
I went over and over in my mind how I would not instantly clamp down hard if there was a fall, feeling certain that a longish dynamic ride for the leader that ended with a stop would be considerably more welcome than the much longer fatal ride that a non-dynamic belay might provide. I felt some gratitude for an old-school past that included actually practicing such things; my intentions were not entirely theoretical.
Of course, nothing happened, as is usual. I think I had it covered, but am happy to say we'll never know.
P.S. No calculators were used during this process, nor was the system of differential equations for coupled harmonic oscillators consulted.
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TradIsGood
Chalkless climber
the Gunks end of the country
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Nov 29, 2008 - 04:48pm PT
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JohnR,
I could not get access to the spread-sheet on your server...
EDIT:
BTW. Check the belayer's displacement in your model. It probably will NOT show him moving down.
The force on the tether will grow as the force on the faller side increases (with stretch). Eventually the force may exceed his weight, at which point he will accelerate upward.
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JohnRoe
Trad climber
State College, PA
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Nov 29, 2008 - 05:22pm PT
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TiG
Sorry. It should be accessible again now.
rgold
I feel that the dynamic aspect of belaying (whether intended or not) may be the downfall of many of these models. In the new anchor book, p104, JL claims that "the maximum force a modern belay device can put on the rope without slipping is 2-3kN".
Let's assume for a moment that the force at the belay device is limited to 3kN. Then the maximum anchor force in the factor 2 situation (scenario 1) is about 4kN (3kN plus the belayer). In the "pulley" situation (scenario 2) it will be 3kN to the belayer plus 3/0.7 kN to the climber - total over 7kN. If the anchor is marginal, as in the situation you just described, this is a big difference.
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JohnRoe
Trad climber
State College, PA
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Nov 29, 2008 - 05:25pm PT
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TiG wrote "BTW. Check the belayer's displacement in your model. It probably will NOT show him moving down."
This is "scenario 3", right? I measure the diaplacements downward, and so as this displacement becomes negative, the belayer is actually moving up. I'm sorry the graph is confusing.
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chainsaw
Trad climber
CA
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Nov 29, 2008 - 08:09pm PT
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this topic rules! Bump
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jstan
climber
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Nov 29, 2008 - 08:16pm PT
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GO
At the time I was doing my work cams had as yet to be invented. This is why I talk about observing the area of aluminum which would have to shear in order to result in failure. By looking at the area to be sheared one is able to avoid placements where small rugiosities may cause a failure.
I never tested a cam either in the lab or in the field.
When cams did come out their complexity caused me to hold off on adopting them.
Each of us is conditioned by our past experience. Rgold's past experience revolves around his understanding with quite some precision the forces he is able to withstand. I have learned not to question his judgment. He has always been right and has been so with great regularity. My own experience picking stone in the fields convinced me early on I was completely helpless when faced with a rock weighing 1000#. If a force of that magnitude were applied to my midsection as a millisecond impulse, I have not the slightest doubt as to the result. Not surprisingly I don't propose to do an experiment.
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Karl Baba
Trad climber
Yosemite, Ca
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Nov 29, 2008 - 09:01pm PT
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One important things about cams is they don't have the same sheer problems that nuts do because they expand. (there may be some devils in the details) Just because they drag a bit because of rock texture doesn't mean they blow.
They can trench their way out of soft rock but I stay away from that stuff!
peace
karl
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Largo
Sport climber
Venice, Ca
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Nov 29, 2008 - 10:35pm PT
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RGOLD wrote: "I clip my belay device into both the harness belay loop AND the tie-in knot loop of my anchor rope. This means that loads to the belay device are transmitted to the anchor directly, rather than loading up the belayer's harness first. However, since the anchor rope stretches, the belayer has some opportunity, in the case of the high loads of a factor-two fall, to resist with appropriate stancing, to use Joe's term, and thereby reduce to some extent the total load to the anchor. Since the connection is direct, the increase in load guaranteed (sorry, Karl) by the pulley effect after the break-even point is not a consideration."
That's an interesting and IMO, hopeful new wrinkle on the "direct belay." There's no load multiplication/pulley effect from a standard clip-through redirect, and the two to three foot shank of lead line/tether adds an important dynamic quality into the belay chain, while at the same time allowing for "stancing."
A curious thing per those rare cases of total anchor failure - I wonder how many times the leader actually fell onto the belayer? No way to ever know, perhaps, but in the case of the DNB team, that was last seen alive high in the upper chimneys - it's not steep enough up there to fall over the belayer, and a fall in many places in those chimneys would essentially funnel the leader right into the belayers lap.
JL
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tito
climber
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Nov 30, 2008 - 01:33am PT
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> If both the tie-in and the belay both come off the crotch loop you
> better have a loop of 1" tubular directly backing that up to your waist loop.
No need for the 1" tubular. There's a loop of climbing rope available to clip into, which also serves to reduce the number of single point failures in the system.
> Now here's the critical detail: I clip my belay device into both the harness
> belay loop AND the tie-in knot loop of my anchor rope.
I was taught to do the same. I would think the practice would be ubiquitous by now.
> There's no load multiplication/pulley effect from a standard
> clip-through redirect
Huh? Redirect = pulley effect, so then what's a "standard clip-through redirect"?
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Largo
Sport climber
Venice, Ca
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Nov 30, 2008 - 03:13am PT
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> There's no load multiplication/pulley effect from a standard
> clip-through redirect
Huh? Redirect = pulley effect, so then what's a "standard clip-through redirect"?
You're puling this out of context. There is no pulley effect so long as you clip in as Rich described, unless I'm not visualizing it correctly.
JL
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healyje
Trad climber
Portland, Oregon
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Nov 30, 2008 - 03:34am PT
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sibylle: "What I mentioned earlier - what if a climber that weighs 100 to 120 pounds belays a climber who weighs 180 to 220 pounds? Have any of you caught a leader who weighed almost one hundred pounds more than you? I have. It sucks no matter how you belay them."
Sibylle, it's hard not to sympathize with a situation you clearly encounter all the time. As jstan said, dealing with a large weight differential is an under-discussed affair. But in the end, the onus is on you to mitigate the situation by either tying down or using the sort of hybrid system rgold describes. I still think employing the anchor for that purpose isn't the best idea, but if that's your chosen solution then I hope you beef up your anchors [where possible] for such situations.
Karl Baba: "You still get plenty of "feel" for the climber (like fishing) if you use your hands on both sides of the device when bringing up the second. It's so easy you get a better cool down at the belay and makes it easy to manage the rope for the next lead."
I consider managing and stacking the rope to definitly be part of the craft of belaying and orderly climbing in general; for that matter finding interesting ways of stacking over natural features around the belay can actually make it almost entertaining (I suppose that unavoidably makes me an uber geek)".
jstan: "If someone criticizes another's technique but cannot give a persuasive argument you know right away what to do."
I'm not really trying to be 'persuasive', just give my opinion - folks can take or leave it. But when I say belaying off the anchor "divorces you from any number of sensory pathways" I mean way more than just the 'fishing' part of things, but it quickly gets back to stancing issues and facets of a belayer's interaction with, and on-going knowledge of, the anchor and constituent elements. Even knowing what's happening after a fall comes into play as well.
rgold: "If you do not accept that some of the time you are belaying off anchors that may not be bombproof, read no further."
There's probably some influence on this topic due to the kind of rock folks are used to. I'm a sandstone climber by history and proclivity. I suspect the notion of an 'anchor' for me connotes something a bit different than for Valley climbers used to what, for me anyway, is granite of an almost alien hardness. Maybe there's a generational element at play as well; back in the day we tackled lots of lines and FA's with a set of hexs and one of nuts and on occasion arrived at a belay or the end of a rope with just a stopper or two. The whole notion of an 'anchor' was definitely a means of last resort for stopping a partner's fall in those situations. Stancing played an enormous role in our climbing as we tried to never rely on anchors unless there was absolutely no other option, no matter how bomb.
rgold: "It does mean, for upper belays, that the belayer has to be actively engaged in the belaying process,"
"Actively engaged", in as comprehensive a context as possible, would seem the name of the game everytime.
Karl Baba: "A not-insignificant advantage of the gri-gri belay of the second is this. If there is a spray of rockfall from above (and this happens!) It would be possible for the belayer to fall and the belayer to get hit by rocks at the same time."
This I do consider an edge case I'm not willing to let drive how I belay beyond where I put a belay and how much slack I give myself to move in cases where known or suspected loose rock is involved with a pitch.
GOClimb: "To elaborate on point 2: What I found was that very minor features of the placement (nearly impossible to determine without a trained eye and plenty of time to fiddle) can mean the difference between a piece ripping out versus holding, in relatively small falls (on the order of FF = .2 - .5) Factors like a little grit in the crack, or the relation of one lobe on versus behind a crystal."
I think that placing pro well in general requires being fairly critical and paying attention to a very fine level of detail. I found once I started doing that my pro and anchors improved. Then again, it also greatly increased my awareness and consideration for all the 'grey areas' of climbing. Those grey areas are what reiterated for me the importance of stancing and having the human body in the 'chain' to protect the anchor.
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Karl Baba
Trad climber
Yosemite, Ca
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Nov 30, 2008 - 10:16am PT
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"> Now here's the critical detail: I clip my belay device into both the harness
> belay loop AND the tie-in knot loop of my anchor rope.
I was taught to do the same. I would think the practice would be ubiquitous by now. "
I'd have to question the importance of this. Let's say the belay device is just clipped in the belay loop and you're tied into the loop of rope which is also captured in the harness within one inch of the belay loop. Aren't we talking about a few inches of difference before, in effect, the belay device is weighting the tie-in rope in the same manner?
You do get a bit of redundancy but I've only heard of one belay loop failing and that was a freak accident and not in a fall. In any case, you're still trusting one biner and device to save the day. On the other hand, this whole belaying scenario is going to a make it hard to either escape the belay or set up a haul to get an injured or unconscious partner back up to the belay. If you have a redirect, it's WaY easier.
Some have said needing to escape the belay or haul the partner are rare things but so are the other dangers to the anchor discussed here.
Peace
Karl
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Karl Baba
Trad climber
Yosemite, Ca
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Nov 30, 2008 - 10:24am PT
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Healyje wrote
"There's probably some influence on this topic due to the kind of rock folks are used to. I'm a sandstone climber by history and proclivity. I suspect the notion of an 'anchor' for me connotes something a bit different than for Valley climbers used to what, for me anyway, is granite of an almost alien hardness. Maybe there's a generational element at play as well; back in the day we tackled lots of lines and FA's with a set of hexs and one of nuts and on occasion arrived at a belay or the end of a rope with just a stopper or two. The whole notion of an 'anchor' was definitely a means of last resort for stopping a partner's fall in those situations. Stancing played an enormous role in our climbing as we tried to never rely on anchors unless there was absolutely no other option, no matter how bomb"
This is for sure true in many ways. Granite and certain sandstone (like sedona) are so different, it's like the difference between jumping out of an airplane with a parachute and free-soloing with a base rig.
In the valley we almost always have way bomber anchors but "stancing' is often very limited because of so many hanging belays and tiny stances.
Peace
Karl
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rgold
Trad climber
Poughkeepsie, NY
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Topic Author's Reply - Nov 30, 2008 - 01:30pm PT
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Karl has taken exception to the anchor clip-in method I described: "I'd have to question the importance of this. Let's say the belay device is just clipped in the belay loop and you're tied into the loop of rope which is also captured in the harness within one inch of the belay loop. Aren't we talking about a few inches of difference before, in effect, the belay device is weighting the tie-in rope in the same manner?
It could conceivably be similar if you cranked the anchor tie-in tight enough, but you'd be uncomfortable, and I've just never seen anyone do this in practice. Even cranked tight, you'll have the anchor tie-in pulling up on the harness and the belay loop pulling down---opposing forces that threaten harness integrity in the factor two scenario. Since people never ratchet up their tie-in this tight in the real world, what actually happens is what Sibylle described and I responded to: a fallen second ends up with a lot of weight on the harness and the belayer experiences all the discomfort she alluded to. In the set-up I described, the belayer experiences no stress whatsoever.
In the case of a factor two fall, the difference is that the belayer's harness and body aren't subject to the violent impact of the shock, giving them a better chance of staying in control, not to mention sparing them the bruising the harness would otherwise impart. The belayer is less likely to be flung off their stance and become another falling object the anchor has to stop, and the belayer's harness is less likely to be damaged by large opposing forces. In this regard, perhaps we should attend to what the harness designers have to say about this situation. Here is BD harness designer Tom Jones, as quoted by Chris Harmston on rec.climbing in 1995:
"The leader could fall directly on the belayer with no intervening pieces
so the belay loop system must be able to hold that 3372 lbs of force. This
brings up why it is important to clip your belay device into
both your belay loop and the loop of the rope on multi pitch climbs. The
lead rope should be your primary anchor - your primary link from your
harness to the anchor - because it is dynamic and flexible. Your belay
biner should connect directly to the rope tie in loop so that the forces
of the belay can link directly to the anchor. Otherwise, the forces from
a severe fall would run from your belay biner to the belay loop,
to the harness, to the rope loop to the anchor. This would tend to rip
the harness apart and the results are very unpredictable. It is much
better to have the forces transfer as directly as possible to the strong
point in the system - your fully equalized, three bomber pieces anchor."
I learned the technique from this post.
By the way, although I don't necessarily agree with a harness designer's take on anchor construction, honesty and a respect for getting at the truth oblige me to also record that Tom said,
"The worst case fall is where the leader does not get any pieces in, then pitches
off and falls directly on the belay. Climbers are usually smart enough
to clip the lead rope into a draw on the anchors, so that the belayer
experiences an upward force, but this is not always the case."
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Steve Grossman
Trad climber
Seattle, WA
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Nov 30, 2008 - 01:58pm PT
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Having sucked many a light belayer up into the first piece of pro in line, I always chuckle at this Sheridan cartoon.
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Dr. Rock
Ice climber
http://tinyurl.com/4oa5br
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Nov 30, 2008 - 02:00pm PT
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So the guy who happens not to be sittin at the campfire at Camp 4 misses out on all this and ends up in ER, see the power of the internet and how you guys are saving lives as we read.
Thank you and the best thread yet for me at least.
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Steve Grossman
Trad climber
Seattle, WA
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Nov 30, 2008 - 02:59pm PT
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It seems that most bad anchor/ long runout above scenarios involve slab climbing where it is usually possible to reel in a substantial of rope before the leader actually lands directly on the station or the belayer's waist carabiner. For that reason alone, I would usually favor belaying from my waist carabiner rather than from the anchors directly.
If the anchor is truly crap and you have no viable options but to commit to it then I would much rather use all of the shock absorbing power of my lower body on the stance holds before loading the suspect anchor points with or without load limiters in between.
Doing your homework about the route in question and bringing along that cumbersome old bolt kit when venturing out on the obscure would seem to be a better approach to surviving poor belay stations.
Always take a thorough look around and make sure you are actually on route and that climbing past the poor station isn't a viable option.
My usual approach to a shitty wall stance is to climb past it and tie off a few pieces above. Freeclimbing with no Jesus Nut in sight clearly doesn't allow for that option
If the station is really that bad then down climbing and quitting the route from more reliable protection below on the pitch may become a better option. While down climbing (using the crap station as a top rope anchor effectively) a prussik or other locking knot can be employed to potentially shorten the lead fall that would result if the crap station above actually failed under load.
Sometimes it is better to not commit the entire party to a poor station and try to work your way out of the situation while still on the sharp end. Simo climbing or belaying the second up a bit may also be a viable option to allow the leader to reach a better set of anchors so try to make the best call that you can once the situation is clear to you.
Carry a couple of aid screamers (with the accessory loops removed) around the back of your harness when slabbing about above the rusty bits!
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Karl Baba
Trad climber
Yosemite, Ca
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Nov 30, 2008 - 03:29pm PT
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agree about the screamers.
Steve wrote
"It seems that most bad anchor/ long runout above scenarios involve slab climbing where it is usually possible to reel in a substantial of rope before the leader actually lands directly on the station or the belayer's waist carabiner. For that reason alone, I would usually favor belaying from my waist carabiner rather than from the anchors directly. "
Just to keep the discussion on track, I want to note that virtually no one here as advocated belaying the leader directly off the anchors. The main choices under review for belaying the leader concern dealing with the potential for factor 2 fall by clipping a through the anchor while belaying off the harness, versus belaying off the harness with no directional through the anchor.
It is true that many of these scenarios are slabby where there is no pro off the anchor but sport climbing has also brought us the possibility of factor two falls on the belay as well. (usually no problem with the anchor holding but you still have to catch the fall)
A geek note: Reeling in slack when the leader is in a factor two fall situation actually increases the theoretical force beyond factor 2 because less rope becomes available to absorb the shock. In practice, slab falls are often low force and I've caught myself by grabbing a draw after falling 10 feet on the Hall of Mirrors in Yosemite.
And of course, if you keep you leader from hitting something ledgey by reeling in rope, that's worth increasing the fall factor.
It all depends
peace
Karl
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Steve Grossman
Trad climber
Seattle, WA
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Nov 30, 2008 - 03:37pm PT
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The topic of belaying directly off of the anchors is in play due to Sibylle's observations about European belaying practices a while back in the thread. The only time that I ever do is when managing two ropes and two climbers below from a solid anchor, which is a rare situation.
One other nuance that concerns me is the potential for cross loading the gate of the waist locking carabiner if the decision is made to catch the fall without clipping into the station.
Assuming multiple poor anchors, I would opt to clip the station with an aid screamer on the weakest anchor point to help dissipate the force of the lead fall. I would rely on a close tie in to the screamer protected attachment to the other anchors to save my ass should the clip in point fail under load with minimal swing or drop on to my waist carabiner.
I would rather belay the second up a bit and continue leading through than drop way down below the anchors to get more lead rope in play while belaying the runout leader on the next section.
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healyje
Trad climber
Portland, Oregon
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Nov 30, 2008 - 03:42pm PT
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I haven't done a bunch of slab climbing outside of a day or two of getting schooled at Whitehorse, but I've used and set no shortage of sketch anchors. Seems like this might be a good place for Piton Ron to pipe in on the topic as I suspect he's seen his fair share as well.
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johnboy
Trad climber
Can't get here from there
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Nov 30, 2008 - 04:38pm PT
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A geek note: Reeling in slack when the leader is in a factor two fall situation actually increases the theoretical force beyond factor 2 because less rope becomes available to absorb the shock.
I'd of thought that for every foot of rope your pulling in, your also shortening the fall by that many feet. Kind of keeping the FF the same. No? Anyone?
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rgold
Trad climber
Poughkeepsie, NY
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Topic Author's Reply - Nov 30, 2008 - 04:42pm PT
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Karl Baba wrote: "A geek note: Reeling in slack when the leader is in a factor two fall situation actually increases the theoretical force beyond factor 2 because less rope becomes available to absorb the shock."
Here's the full story for anyone interested in geekly pronouncements: The effect on the fall factor of reeling in rope depends on what the fall factor is to begin with. If the fall factor is 1, then reeling in rope makes no difference---the fall factor stays at 1 (but the fall is still shorter than it would have been, so a leader would be kept off the ledge or ground with no anchor load penalty).
If the fall factor is not equal to one, then reeling in rope causes the fall factor to increase its distance from 1. So if the fall factor is bigger than one, reeling in rope produces an even bigger fall factor, as Karl notes, but if the fall factor is smaller than one, then reeling in rope produces a smaller fall factor (although never smaller than half the original fall factor).
One of the things we fog-enshrouded ones are fond of doing is splitting hairs, and the current situation is no exception. Reeling in rope is different from the "running belays" used for years on Southern friction slabs (I'd love to call this the Viginia Reel) and more recently popularized on ghastly UK headpoints. No rope is reeled through the belay device, the belayer tries to take up slack by running away from the anchors. This practice always reduces the fall factor, although the velocity of the belayer away from the anchor might ultimately add to the anchor load. Neither of these considerations is primary, since the name of the game is to keep the leader from the ever so reality-based experience of decking.
Johnboy, things don't work the way you are thinking because you are dealing with a ratio, and H/L is not equal to (H-x)/(L-x) unless H=L. If H isn't equal to L, analyzing the sign of (H-x)/(L-x)-H/L gives you the results just stated. For example, 2/3 =(3-1)/(4-1) is smaller than 3/4.
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Steve Grossman
Trad climber
Seattle, WA
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Nov 30, 2008 - 05:09pm PT
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Ahh yes! The fall factor 2+ scenario involving the overweight belayer leaping into the frozen bergschrund on a long tether of slings as his unprotected leader goes flying by the lone Gri Gri!
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tito
climber
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Nov 30, 2008 - 06:49pm PT
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> Huh? Redirect = pulley effect, so then what's a
> "standard clip-through redirect"?
>> You're puling this out of context.
No. Your writing was poor. I see what you were trying to say now. This:
> There's no load multiplication/pulley effect from a
> standard clip-through redirect...
should be:
> There's no load multiplication/pulley effect [as you would get]
> from a standard clip-through redirect
> I'd of thought that for every foot of rope your pulling in,
> your also shortening the fall by that many feet. Kind of keeping
> the FF the same. No? Anyone?
Here's a concrete example. Climber is 10 feet above the the belay. Belayer is belaying off his waist. Climber falls before getting any gear in. If the belayer locks off and braces for the impact, then you have a factor two fall:
20 foot fall / 10 feet of rope = 2.0
Now suppose the belayer yards in 3 feet of rope while the climber is falling, e.g. the belayer whips one arm's length of rope through the belay device and then locks off. In the first part of the fall, the climber would still fall until he was even with the belayer(10 foot fall), but then instead of falling an additional 10 feet, the climber would only fall 7 more feet. Also instead of there being 10 feet of rope out to absorb the force of the fall, there would be only 7 feet of rope out when the climber impacts the end of the rope. Therefore the fall factor is:
17 foot fall / 7 feet of rope out = 2.4
As rgold pointed out 20/10 does not equal (20 -3)/(10-3) = 17/7, so the fall factor is higher if the belayer yards in 3 feet of rope in order to make the climber's fall 3 feet shorter.
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Largo
Sport climber
Venice, Ca
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Nov 30, 2008 - 07:32pm PT
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What do you suppose are the viable conclusions we can take away from this conversation per actual procedures??
JL
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Ed Hartouni
Trad climber
Livermore, CA
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Nov 30, 2008 - 07:41pm PT
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been following all of this, lost on the re-direct discussion.
I employ a redirect to bring up the second, usually this is a separate piece then the anchor, and though it is subject to the "pulley effect" the total force is not likely to be much larger than the sum of our two weights... A decent placement can handle this, usually it is a bomber placement.
I have one experience with holding a fall off a single piece. It was on Anguish, in the Traps. My partner was leading off on the third pitch from the large belay ledge. This last pitch is less than 50 feet long. I'm not sure how far out Mike was, he put in a good #3 Chouinard Stopper on a nylon runner, and then went up to the overhang. He didn't pull it off and was free falling coming to a standing, but hard, landing on the belay ledge, so all in all, probably less than a fall factor 1. I was pulled up by the rope from the force of stopping his fall.
I'm guessing this is around 5 kN impact force, most of the job of stopping the fall is the rope. The anchor system keeps the fall factor constant, and the belayer stationary, the belayer keeps the rope locked off...
The Chouinard #3 stopper is rated for 2600 lbs... it was welded pretty well into the crack.
My "anchor" was a 1" tubular tape draped over a rock flake (not my proudest effort).
I looked over to him and asked "are you ok?"
"My feet hurt" came the reply, I'm sure we both had the same metallic taste in our mouths.
We climbed off something easy to the right. I think he even went up to get the nut out, he may still have that nut.
I believe the forces were probably less than what we calculate, probably significantly less. Lessons learned: 1) build a bomber anchor for the belay, no matter what climb you're on, 2) get pro in before the crux, 3) don't count on over-engineering, but be happy when it saves your ass...
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Ed Hartouni
Trad climber
Livermore, CA
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Nov 30, 2008 - 07:48pm PT
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John posted before I completed my post...
as for the answering the question "should the leader clip the belay anchor?"
I'd say "no" because of the "should"
In the case where the belay is bomber, there should be no need even though clipping the anchor doesn't matter. A leader fall will likely be held whether or not he has clipped in.
In the case where the belay is jingus, then obviously the answer is no, the leader should not. The increased risk of blowing one of the anchor points could significantly compromise the entire anchor. The whole point of a multiple anchor is to benefit from the collective action of the system. This is defeated by relying on a single element of the anchor.
That's how I see it...
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Mighty Hiker
Social climber
Vancouver, B.C.
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Nov 30, 2008 - 07:48pm PT
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It would be hard to generate a factor 2 fall while slab climbing, even with no anchors between belayer and leader. A great deal of the energy from the fall is likely to be absorbed by friction, sliding, tumbling, etc. Nominally the distance fallen is twice the distance from belayer to climber, but as the empirical comments above note, and my experience agrees, they're usually not very high-impact falls.
In terms of take-away, my suggestion is that this discussion underscores:
The importance of knowing how to place good anchors in and of themselves, before trying to make belays. (Aid climbing helps, a lot. An apprenticeship, too.)
A high level of environmental awareness and planning in creating anchors.
KISS - the priority is solid anchors, to which the belayer is securely attached, and for the leader to place several sound places of protection immediately above the belay.
Good belay anchors always having priority, e.g. over running out the rope, and even stances.
Using solid natural stances where available. A well-braced sitting or standing belay has considerable merit - see Belaying the Leader.
The more complicated stuff, such as serene, force multipliers, force calculations, sliding Xs, equalettes, cordalettes, etc.
Given that many modern guidebooks are quite detailed, perhaps they could say a bit more about what the various belays on routes offer in terms of stances, anchor opportunities, etc. In context of the nature of the route, but informing about likely opportunities and problems. And emphasizing that just because it's a climb, doesn't mean there will be bolt belays - I'm really very concerned that a discussion like this will cause energetic learners to in effect throw up their hands and say "What the F is wrong with just putting in a bolt belay, if it's such a big production to do otherwise?"
Edit: Slightly changed, I hope for clarity.
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Ed Hartouni
Trad climber
Livermore, CA
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Nov 30, 2008 - 08:04pm PT
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Mighty Hiker raise a question which leads to another way to get at this question. MH essentially asks, "if building an anchor is so complex that the risk of doing it wrong is high, why don't we just bolt every belay?" (presuming, of course, the bolts are bomber (but that is another set of discussions).
My question to all the experienced people out there is this: what is the list of worst falls you held (or took) and the details, so far as you can recall, of the anchor, the distance of the fall, the amount of rope out, etc.
Since testing various anchor systems must require risk of the testers, no real surrogates are possible, we don't test how well we do...
...but many of us have been tested. It would be very useful to compile this list of tests and understand them as well as we could to help derive some information regarding the effectiveness of anchors.
Few of us have died this way over the years, the anchor "systems" that were employed varied greatly, John's book being the best systematic description of what an anchor should be... but we lived with a lot less in the past.
Were we just lucky?
I think not.
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johnboy
Trad climber
Can't get here from there
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Nov 30, 2008 - 08:54pm PT
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Thank you rgold for explaining that in such a thorough and clear way.
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Mighty Hiker
Social climber
Vancouver, B.C.
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Nov 30, 2008 - 09:23pm PT
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Not that I'm suggesting that we SHOULD have bolts at all belays - far from it. But others might be getting that idea. They might look at this discussion and in effect say "All these very knowledgeable and experienced people don't really seem to agree on what's necessary. How can we be expected to figure it out?"
Another perspective is gear. Most of my marginal belays may have had as much or more to do with simply not having enough of the right gear, as opposed to not knowing what to do with it. BITGOD, if you had a set of hexes, a set of stoppers, and some slings, and your partner did, you sometimes came up short and had to improvise, sometimes not convincingly. Even when some early Friends got added to the mix.
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TradIsGood
Chalkless climber
the Gunks end of the country
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Nov 30, 2008 - 09:55pm PT
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Gaaaak!
I think Mighty Hiker really is on to something. Why the heck not bolt the belays - at least of any oft-repeated route?
Solves a speed problem. Even noobs should then be able to set up a safe anchor efficiently. Highly experienced trad leaders should be able to set up an anchor at least as efficiently as a noob!
What is the goal here? Climbing, or setting up silly arse multi-piece trad gear anchors (SAMPTG) and thumping your chest about how old-school and smart you are? (We have already seen that most old-schoolers really aren't that smart, after all. Even Largo can't do the physics. And Who TF wants to be doing physics - even if you can - while you are out having fun.
(I have honestly never heard of a golfer discussing physics - except for one guy who writes books on it - and I doubt he wants to worry about it while playing.)
It reduces wasted time, increases climbing time of you and any following party.
Then the only people who need to set up a SAMPTG anchors are FAs, or people still climbing routes still awaiting a proper bolting party.
Not exactly the target audience of the author semi-responsible for the existence of this thread.
Of course, if we bolt all the belays, there will be a few less disasters every year, over which we can pontificate and second-guess with less than full data on forums such as this.
Could be the death of rc.com and gunks.com, but we have politics here!!!!!!!!!!!!!!!!!
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Mighty Hiker
Social climber
Vancouver, B.C.
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Nov 30, 2008 - 10:02pm PT
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TiG: "Here fishy fishy".
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TradIsGood
Chalkless climber
the Gunks end of the country
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Nov 30, 2008 - 10:09pm PT
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Oops. FAs and parties who got so far off-route they couldn't find the anchor.
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Patrick Oliver
Boulder climber
Fruita, Colorado
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Nov 30, 2008 - 10:12pm PT
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Rich, you and most everyone here are too advanced for me, in this discussion. I barely got through general math II, but got A's in English. Strange. And so I have probably missed most of the point of this thread, in part because (as I muse) I have no left-brain activity. It's all artistic, poetry, music, you know, that stuff.... Anyway, though, I think I can say I have learned a few practical things from direct experience, and they wouldn't probably apply in the strictest sense to the main line of this thread. But let me just throw out that one can learn lots by really visualizing and getting a sense of each situation. In addition, silly as it will seem to some, there is some kind of factor of miracles and luck, and such mysterious kinds of things, and I'm sure I will lose some here but let me share a wild story just for fun...
Breashears and Erickson and I, in 1975, one day went up to do Catchey and Catchey Corner (down on the right side of the Cookie). We pretty much breezed up the first pitch, and Breashears was walking up Catchey Corner (pretty stiff, strenuous 5.10, or some might think easier 5.11, not sure, but not so easy to protect with nuts, if I recall). Breashears was in the best shape of his life. As Erickson belayed, I ambled over to the west, about thirty feet, to the other end of the ledge to examine the rappel anchor for when we did the retreat. Suddenly I had something that felt like a psychic prompting. I turned and hurried back across the ledge. Without thinking, I put both my hands on the rope that was going up the wall to Breashears. Erickson looked at me as to wonder what the heck I was doing. Mind you, Breashears had led up about 50 or more feet, I'm guessing, and was standing where the corner leans up even more steeply to the right. He had only a number one stopper, with one mil cord on it, between him and us. He was trying to place another nut, and fiddled with it. Like the young kid he was, exuberant, impatient, he decided to work on the nut with both hands, to get it in, and forgot the other hand was holding him in. He let go and was instantly airborne. I pulled in a bunch of rope and, by virtue of this action, slowing and controlling how the rope tightened against Erickson, gave Breashears a perfect dynamic belay. The tiny nut held. Had the belay been just what Erickson could do, or if the nut had pulled, Breashears and possibly also Erickson would have gone on past the ledge -- a scary thing even to think about. I don't know to this day what directed me, that moment, to hurry back across the ledge and over to the rope and grab it. But the second my hands touched the rope was when Breashears fell. So life, maybe we can say, is more than numbers and more than precise equations, but also a lot of beauty and mystery and things and things a little beyond us, as well. That's where my spirit lies, most of the time, that realm of the mysterious, as that's what it has always been for me to be with friends and to climb and to be out in such ridiculously beautiful terrain. Though I greatly respect you guys, such as you Rich and John Stannard and others here who have such brilliant and more more realistic, down to earth, mathematical minds. I often feel I am still a beginner, because there is so much always to learn.
Pat
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Handjam Belay
Gym climber
expat from the truth
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Nov 30, 2008 - 10:44pm PT
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noone has mentioned jumping off the other side of the ridge yet
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rgold
Trad climber
Poughkeepsie, NY
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Topic Author's Reply - Nov 30, 2008 - 10:51pm PT
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Pat, don't be too impressed with the math and physics. As Karl keeps reminding us, it provides only a shadow, and possibly a misleading one, of the reality it tries to model.
On the other hand, models have something to tell us about the underlying nature of things in situations, like many that occur in climbing, in which human variation overwhelms underlying patterns. I sometimes think of what happens if you take a collection of weights of different sizes, held together by chains of different lengths. Throw the thing and it looks chaotic, with weights flying up and down and whipping around crazily. A person who threw such things regularly would probably come up with some rough notions of where they were headed and what path they would take. But it is extremely unlikely that they would ever, on the basis of observation, arrive at the idea that this whirling dervish of an object has something called a center of gravity, and that center follows a very simple, entirely predictable parabolic path as the cloud of connected objects moves, apparently chaotically, through space.
A practical man may say that this theoretical trajectory is of no use to him if, even though it misses him, some outlying orbiting weight clocks him on the chin. And he would be right. The trick is to figure out what the models have to say that is useful, if anything. The problem the geeks have (y'know, I don't really feel all that much like a geek), is that they enjoy the models a bit too much, and in so doing run the risk of mistaking them for the reality the models only approximate, at best.
And so there will always be a wide field for the human spirit and its mysterious intuitions, with lots of room for us science types to admire your wonderful gifts, even as you respect ours.
Death, at least of the spirit, begins as soon as we get it into our heads that we are not beginners at life, and so it is with climbing as well. Karl started a thread on what "really" causes accidents. Perhaps the answer is, "forgetting, after all these years, that we are still beginners."
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Patrick Oliver
Boulder climber
Fruita, Colorado
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Nov 30, 2008 - 11:43pm PT
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Wow, that was very beautifully said. Thank you, Rich.
Pat
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Karl Baba
Trad climber
Yosemite, Ca
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nice post Rich
"A practical man may say that this theoretical trajectory is of no use to him if, even though it misses him, some outlying orbiting weight clocks him on the chin. And he would be right. The trick is to figure out what the models have to say that is useful, if anything. The problem the geeks have (y'know, I don't really feel all that much like a geek), is that they enjoy the models a bit too much, and in so doing run the risk of mistaking them for the reality the models only approximate, at best. "
Peace
karl
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Karl Baba
Trad climber
Yosemite, Ca
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Rgold wrote
"By the way, although I don't necessarily agree with a harness designer's take on anchor construction, honesty and a respect for getting at the truth oblige me to also record that Tom said,
"The worst case fall is where the leader does not get any pieces in, then pitches
off and falls directly on the belay. Climbers are usually smart enough
to clip the lead rope into a draw on the anchors, so that the belayer
experiences an upward force, but this is not always the case.""
We have had a productive discussion and I think folks probably understand there are tradeoffs involved in the choices we make to redirect using the anchor.
So what I'd really like to comment about is the integrity and honesty with which you posted an educated opinion contrary to your own position. After our period of political threads, and politics in general, that sort of attitude is to be applauded and respected.
Thank you for setting a fine example
Karl
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JohnRoe
Trad climber
State College, PA
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healyje's rules sum it up for me
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TradIsGood
Chalkless climber
the Gunks end of the country
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The majority of the belays I have used tended to be on ledges. Maybe because that was where there was a good stance. Maybe because trees grow better there. Most do not really offer the possibility of a factor 2 - you can't factor 2 bouncing off a ledge.
In fact, I have been wondering about rgold's story about being slammed onto his thighs with a factor 2 fall. Really skinny ledge and the climber did not hit the ledge on the way past?
Heck! Speaking of trees, they often are a single piece. Good for a belay of the follower. If it happens to be above you, which is not all that often, and you want a hanging belay, or must accept one, you can make the distance to the tree whatever you like with regards to the next pitch by just downclimbing/lowering to the next belay stance.
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rgold
Trad climber
Poughkeepsie, NY
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Topic Author's Reply - Dec 2, 2008 - 02:05pm PT
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"In fact, I have been wondering about rgold's story about being slammed onto his thighs with a factor 2 fall. Really skinny ledge and the climber did not hit the ledge on the way past?"
A flake handhold broke when we was in a layback position. He sailed right over the ledge, which wasn't really skinny---it was essentially big enough for me to fall to my knees and still be on the ledge.
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the Fet
Knackered climber
A bivy sack in the secret campground
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Whew, I finally got through reading this thread. Lot's of good analysis and ideas.
A couple things I've been thinking.
1. If there are 3 pieces of pro for the anchor (the only placements available) it seems it would be better to build your anchor from 2 pieces and have the 3rd piece independent of the anchor for the leader to clip into as the "jesus" pro.
2. If there are 2 bolts I'd rather have the leader clip the powerpoint than the highest bolt. Preferably with a sreamer.
Here's an image from the dike a few years ago. Possiblity of a nice 100+ footer factor 2. Anchor is a sliding-X with limiter knots, a rope tie in for the belayer, and a screamer used as a draw on the powerpoint.
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Largo
Sport climber
Venice, Ca
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He wrote: "1. If there are 3 pieces of pro for the anchor (the only placements available) it seems it would be better to build your anchor from 2 pieces and have the 3rd piece independent of the anchor for the leader to clip into as the "jesus" pro."
If I was on three sort of sketchy pieces and a leader fall seemed possible directly off the belay (with no Jesus nut available), I'd probably equalize (sliding X) the two strongest placements, clip the lead rope through this pair and belay off the remaining piece.
Why? FIrst, there is no system that equalizes three pieces without introducing a lot of extension, which might be a bigger consideration than equalization - no one really knows for sure. Anyhow, since the "top piece" always absorbs the most force, by making the top piece the equalized pair, you stand the best chance of it holding should the leader ping for a Factor Two whipper.
If the placements were total sh#t I'd probably equalize everything as well as possible and skip the directional and try and catch the whipper off my waist.
JL
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JohnRoe
Trad climber
State College, PA
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Love the picture.
I remember a bolt on that pitch somewhere though.
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dirtineye
Trad climber
the south
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Too worn out to read the whole thing, but just in the first page I too want to say, "Good idea, Clint.".
And I wonder if one day all bolted anchors will have three bolts, with one 5 feet above the other two, for climbs where there is no pro for a ways off the anchor, just so the ff 2 or even 1.77 will be pretty much impossible to accomplish, at least if you are of sound mind.
Hmmm I bet that sounds too commie-pinko namby-pamby to the real he-man climbers, so it'll probably never happen.
Guess we'll just have to do what Clint's friends did, which again sure seems like a good idea.
I'll have to read more of this one later. Seems like one of the few really good climbing threads to come along in a while.
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Ryan Tetz
Trad climber
Flagstaff, AZ
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If the 3 placements were all sh#t, I'd try to belay somewhere else. You can argue with me this doesn't always work or sometimes you have to use this or that crappy belay.
I'll say 99% of the time you can avoid this. There's a lot of solutions, the leader could build his anchor on the ledge, then continue climbing up higher up the next pitch till the next bomber piece is in up above before coming back down to belay at the not so ready for factor 2 anchor.
Belaying in the middle of the a pitch, build a hanging belay, get 2 bomber cams in somewhere.
Build your anchor high, often the small cracks right above the great belay ledge, might not be so hot for taking pro/out of gear that size at the end of a long lead, the rock is poor quality etc, I'll climb up 10-20 feet and get some solid high gear in then tie it back in with the belay, if its really desperate the climbing rope can be used here, but often a cordalette untied as a long single strand can get a couple pieces together.
I most often run into mandatory bad anchors on old bolted routes with quarter inch or even older bolts star drives etc. Here I will belay directly off my harness as Largo mentions. Avoiding any possible force on the anchor if possible.
Heading in to a "potential" factor 2 situation. If the anchor is in one obvious given spot for say and the climbing looks devious above sometimes i'll have the belayer tie into the anchor but tie in about 10-15 feet down from the anchor, I'll tie them in low with a clove as they are seconding up. Then I'll clip the anchor as I lead out and it won't be quite the gut wrenching factor 2 if I blow the move, say on something like some of the potential situations on the DNB.
When we did the rebolting of the Virginia variation to Tangerine trip on El Cap, some of the fixed anchors were terrible up there. I'd equalize everything possible. On one particularly bad anchor I barely felt good enough leaning back on it let alone hauling two bags and having a guy jug the overhanging fixed line. I climbed 3 rivets up the next pitch and equalized them all into the anchor using the end of the haul line and tied one more rivet in from the side. It was a good thing, I linked it all together. As Eric came up the rope I watched one of the 2 bolt anchors hangers slowly crack and rip in half just from the weight of jugging.
There's some trick equalization techniques for using the climbing rope to anchor and still getting a master point and a few knots I like. Hard to explain without seeing pictures though.
-----side note----- I tie my cordalettes in a loop for regular use with a flat overhand "EDK" knot, 2 of of them for redundancy, this allows me to untie it quickly into one long strand. Throw a bite on an end or both and equalize spaced out anchors.
For the record I'm opposed to the idea of bolting all anchors on big routes up and down as some kind of safety. That seems ridiculous. I can see it a bit more part of the time in places like red rocks with sandstone etc, but just dumb in granite.
-----(OT) I do however agree with the bolts on say cathedral peak summit not particularly for myself or a lot of people up there, but with all the crazy clusterfrig on the mountain most days they increase safety up there by a large enough margin to get the approval stamp.
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madbolter1
Big Wall climber
Walla Walla, WA
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Dec 10, 2008 - 12:49am PT
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All very interesting. However, I've got quite a bit of first-hand experience holding hard falls, and two in particular rise to the top.
Having actually held two basically factor-2 falls (no real-world fall is ever genuinely factor-2) like the theoretical ones described, I can attest to a few things.
First, clipping an anchor placement (in the absence of a nearby non-anchor protection placement) does produce a massive pulley action. In both falls I was launched about six feet up out of my dangling hammock until my belay plate slammed into the 'biner of the anchor bolt. Belays of falls like the ones theoretically described WILL be dynamic. The belayer is gonna get launched. Period. And that's a good thing!
Second, both falls were held by 1/4" button-headed RAWL bolts, not exactly known for their amazing strength. The fact that the belayer WILL get launched goes FAR toward reducing the total load on the anchor placement (not to mention the belayer!). Again, the pulley action and launching effect are exactly what you want!
Finally, I simply can't imagine trying to control falls of that force and violence had they landed on my harness instead of that anchor bolt. I'm sure I would have managed somehow, but probably with injury (at least badly burnt hands). When I say "violence," I mean it. The two falls (one after the other) completely trashed a brand new lead rope. DEEP, flattened spirals were burned into the core, and for about forty feet from the tie-in knot the rope became very stiff and wiry. Talking about the theoretical forces does not translate in most people's minds into the REALITY of actually holding factor-2 falls. I'll put a placement between me and that falling leader ANY time. Even a placement that might pull will reduce the force some, and you have GOT to reduce the force hitting the belayer as much as possible.
The only caveat to my assertions is if you are at a death anchor of some sort, where each and every piece is essential and critical to the anchor's consistency. In that event, I believe that if the leader takes a factor-2 fall, all participants are probably dead anyway. The actual forces are simply immense! Not clipping an anchor placement is a very fine theoretical point in that event, and it's hard to translate that into anything real world.
So, except for that one caveat, when I'm leading I always clip an anchor placement, and I always ensure that my leader does as well.
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mark miller
Social climber
Reno
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Dec 10, 2008 - 12:57am PT
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With 4 decades of belaying and catching falls from leaders trying to do harder stuff then I would ever conceive of getting on, and catching more falls then most could ever imagine,,, I'm going w/ P. Haan's recommendation , it's worked for me over a 100x.......
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dirtineye
Trad climber
the south
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Dec 10, 2008 - 02:36am PT
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Read a little more, like this statement a lot.
"Sometimes it is better to not commit the entire party to a poor station and try to work your way out of the situation while still on the sharp end."
I have to say the freedom of doing new routes allows one to pull out the old drill kit in these circumstances, and the egos of my valued partners are sufficiently tamed at this age that they don't really care about purity or one more death route to their credit, ROTFLMAO!!!
There is just one problem though, with NC ethics, and that is that traditionally, if a climb is under 5.8, it gets no bolts, period. You just run it out. Yeah that's a conflict with the statement right above it, oh well, sue me.
Having led one such pitch (140 feet, no pro, pretty much featureless friction slab) while it was mostly wet, and at the time I had no problem with it, never felt in real danger, I have to wonder, am I just plain stupid, or was my slab climbing pretty darned good at one point? HAHA, could be both!
I would say this whole discussion should bring up the question, "Should we be on this route in the first place?"
The begged question under the whole discussion is some version of, "Are we good enough for this climb?", or, "Should we come back on a better day?" or something like that.
After all, if you think the climb is trivial for your ability, you would not be having any qualms about the gear, the anchors, the fall factors, etc.
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jstan
climber
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Dec 10, 2008 - 10:56am PT
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When testing ropes we do a couple of things. We assume the anchor of the test rig is bomber and we are willing to sustain really large loads so that the elasticity of the rope allows it to absorb the leader's energy. Out on the rock neither of these may be true. If we can't hold these large loads the total distance the leader has fallen becomes important again. Because that is the energy that has to get turned into heat someplace other than in the rope.
If the fall factor analysis somehow convinces us all that the total distance fallen is never important and we start climbing that way, I will be of the opinion Mammut should never have allowed their test procedures and analysis to leave the lab.
This is probably one of the very best threads ST has ever seen. Someone needs to print up hard copies of it which may be posted in climbing gyms all across the US.
As soon as possible.
FWIW
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Steve Grossman
Trad climber
Seattle, WA
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Dec 10, 2008 - 11:52am PT
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"To translate that into anything real world" is the point here, is it not?!?
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jstan
climber
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Dec 10, 2008 - 09:08pm PT
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I believe Mr. Grossman has hit the central point here. What are the real data?
Just as it was in the 70's we really need to know what is real and what is not. We fear that more teams of climbers will go bumpity bump down the hill but what to do about it?
What?
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Karl Baba
Trad climber
Yosemite, Ca
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Dec 11, 2008 - 03:06am PT
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George R posted this on another thread and I'm taking it upon myself to repost it on two related threads and this is one of them. The forces in question are particularly magnified if the fall goes directly on the belayer and a piece pulls
Peace
Karl
"On Nov 23rd, rgold wrote:
" John, one thing that worries me, and I have to apologize profusely for not catching it early on, is that Jim's tests on the effect of elongation in the anchor, the ones that lead to the conclusion that elongation doesn't matter, do not seem to me to be properly configured to test the real situation. There was too much energy-absorbing rope in the system, relative to the amount of elongation, leading to insignifcant changes in fall-factor and so a conclusion that might not be appropriate for real anchoring situations. In a real situation, it is the belayer's anchor strand that will have to absorb the belayer's fall (plus whatever load the belayer is holding at that instant). Minimally, the anchor strand will have to absorb a fall by the combined weights of leader and belayer. If that anchor strand is short, say a foot and a half, and if the elongation in the anchor is, say, six inches, then you still have a fall factor of 1/3 with something like 350 pounds, and there is no way this isn't going to load the anchor significantly. This means that the intelligent use of sliding systems ought to involve tying into them as long as possible, given the nature of the stance. "
Right. A general conclusion that anchor rigging elongation (aka extension) is harmless is not supported by any test data.
The Long/Sterling tests simulate a situation in which a climber is rope soloing without a haul bag or belayer or any other significant weight on the anchor. This tells us almost nothing about what happens when the belayer (and/or 3rd climber, haul bag, etc.) falls due to extension. Depending on the circumstances, such a fall could have a very high fall factor (possibly greater than FF 2) on a tied-off rope (no belay to slip and limit force). Or worse yet, onto a static tether such as a sling or daisy chain.
Rock & Ice magazine also did some tests to examine the anchor extension question. (See Rock & Ice #135, July 2004). Their conclusion was extension is dangerous. They also made the error of generalizing from one situation to all situations, however their tests are more relevant to the situation we're concerned with. The R&I test was perhaps extreme (no dynamic rope at all) but they more accurately modeled the situation of the belayer falling on to the belay anchor due to extension.
The key to reconciling the differing test results and to understanding the extension problem is the Fall Factor. In the Long/Sterling tests, extension resulted in insignificant additional force placed on the remaining anchor point. Exactly what we should expect in that situation, because the fall factor was not increased much by the extension. In the R&I tests, the fall factor was high and no dynamic rope was involved, so extension caused a large force on the remaining anchor point. Again, just what should be expected.
It should be emphasized that it is the belayer (and/or other large masses attached to the anchor) that matters. A falling climber may have enough dynamic rope out to keep the fall factor low and minimize additional force from anchor extension. The belayer, third climber, haul bag or whatever may not. They will often be tied (not belayed) to the anchor with relatively little dynamic rope or perhaps none at all. Fall factors and forces may therefore be very high. The issue is how much dynamic rope compared to how much extension with respect to each falling mass in the system.
The Long/Sterling tests and the Rock & Ice tests each tell us something, but not everything, about the potential dangers of anchor rigging extension. If we apply the fall factor concept, and consider ALL the significant masses that are involved in a given situation, we can draw the correct conclusion for that situation.
Again, the issue is how much dynamic rope compared to how much extension with respect to each falling mass.
G "
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dirtineye
Trad climber
the south
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Dec 12, 2008 - 12:41am PT
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Just a "make em eat their vegetables" kind of bump.
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Radish
Trad climber
Seki, California
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Dec 12, 2008 - 12:25pm PT
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I think there was an accident on the East Buttress of Middle Cathedral where a two person team got peeled from the belay. There was alot of speculation on what happened and how could the anchor be riped like that. We did the climb soon after and before we knew about what happened. The belay in question had really hard placements all mostly small. We put in as many pieces as we could spare. Then the climb goes straight up above the belayer who is standing on a very skinny ledge. We could see how just a slip the wrong way for the leader could bring the full leader weight right on the belayer. Though its pretty easy just to climb up to where you can get a piece in. I may be wrong on this total description but I like to know about these accidents to gleen anything that will help.How many actual total anchor failures have there been lately, since the newer gear??
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madbolter1
Big Wall climber
Walla Walla, WA
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Dec 12, 2008 - 02:18pm PT
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Uhhh... YEAH, Steve, that IS the point, and the point is that NOBODY can reliably translate the finest theoretical points into any useful (or even quasi-reliable) real world application.
Show me ONE person that looks at an anchor and thinks thus:
"Ok, strongest placement is a #2 head, good for ~xLbs, translates into potentially (best case) ykNs. Leader potentially out 10 feet before first fall-holding placement, so potential 20 foot fall. He weighs 160Lbs, so potential impact force of zkNs, duration of .01 seconds. Clipping lead rope to placement means 1.72 to 1 fall factor, uhhh... means... uhh... placement must absorb 1.83zkNs (blah, blah, blah... insert ridiculous odds calculations here). Odds of the placement holding: ~1013.8752 to 1. Conversely, the whole anchor (blah, blah, blah... insert ridiculous string of similarly ridiculous and unreliable calculations here), meaning that the odds of the whole anchor holding are 647.8845 to 1. Ahhh... in this case, clearly it's better to not lead-clip that strongest placement. It's our lives, so I'll take those better (although still basically sure death) odds any day!"
Oh, sure, almost all of us do a vague assessment of our anchors. My point is that the FINE theoretical points really don't do much to inform such a decision with ANY reliability. In the real world we simply rate anchors from bomber to sh|t, most far closer to the bomber end of the scale; and my assertion is that any anchor that is so sh|t that you can't find any placement (or two) worth clipping the lead line into is an anchor for which you had better find an alternative. The idea that you're going to belay at such an anchor and DEPEND upon the fine advantage of catching the leader fall onto your harness is, in my mind, absurd. There are ALWAYS so many better alternatives than that.
One might respond that there are situations in which there ARE no alternatives, so we had BETTER get these fine calculations RIGHT.
And I will respond: If you find yourself in such a situation, I hope you live through it because I really want to hear how there was NOTHING you could do but choose whether or not to clip the lead line in anywhere at the anchor. And I'm going to present some alternatives and then note that the fine calculations did nothing to actually inform your decision and that the BEST fine calculation you could perform in that case (akin in reliability, btw) would be to calculate the odds of the existence of the Judeo/Christian God and the odds that He would take you to His bosom if you were to bite the big one. Those sorts of calculations would be a more productive use of your energies, as would bending forward to kiss....
Otherwise, just lead-clip the best anchor placement(s) and enjoy the benefits.
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rgold
Trad climber
Poughkeepsie, NY
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Topic Author's Reply - Dec 12, 2008 - 03:29pm PT
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MB wrote, "NOBODY can reliably translate the finest theoretical points into any useful (or even quasi-reliable) real world application."
I guess then that the entire history of science and engineering is a phantasmagorical illusion and the technology that now entirely shapes our lives has sprung fully-realized from seat-of-the-pants intuitions of visionary inventors.
"Show me ONE person that looks at an anchor and thinks thus...
Nobody does that. Does any driver do analogous calculations when they step on the brake? No. Did SOMEBODY do those calculations? Absolutely. Or closer to home, does anyone placing a cam pause to consider the calculations that lead to the ideal cam shape? Do most of the people placing cams even know what the shape of their cams is and why? Did the fine theoretical points involved in those calculations have any useful real-world application?
"In the real world we simply rate anchors from bomber to sh|t, most far closer to the bomber end of the scale; and my assertion is that any anchor that is so sh|t that you can't find any placement (or two) worth clipping the lead line into is an anchor for which you had better find an alternative."
Given that the overwhelming majority of climbers have never tested an anchor to failure after rating it on the bomber-sh|t scale (or b.s. scale for short), how likely is it that their b.s. rating is 100% reliable? OK then, how about their b.s. rating being accurate half the time---how likely is that? Does it then make any sense, then, to think about procedures that could minimize the consequences of inevitable human fallibility?
"The idea that you're going to belay at such an anchor and DEPEND upon the fine advantage of catching the leader fall onto your harness is, in my mind, absurd. There are ALWAYS so many better alternatives than that."
Three points:
(1) One point of the calculations, is to try to decide whether not clipping the anchor is a "fine advantage" in what I take to be your sense, which is "negligible advantage," or whether it might be a substantial advantage, in terms of the load to the anchor. I don't think we have yet arrived at a definitive answer. Conversations such as the one partially carried out here are an essential ingredient in either achieving that answer or concluding, but not prematurely, that clarity will not be attainable. What purpose is served by attempting to curtail such discussions?
(2) The leader fall, as explained in Chris Harmston's rec.climbing post years ago, should not be caught on the harness. It is essentially caught on the anchor, ideally with a some mitigating resistance from the belayer, but without the force-multiplying pulley effect at the anchor one gets by clipping it.
(3) Since you said there is always a better alternative, one can without hesitation respond that such a claim is false. But semantics aside, what if the belayer misjudges the anchor and so does not opt for the better alternative? Or do we have to assume belayer infallibility in order for any of your points to be valid?
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madbolter1
Big Wall climber
Walla Walla, WA
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Dec 12, 2008 - 03:59pm PT
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rgold, you missed the most important word of the first passage from me you quoted: "reliably." Am I claiming that this discussion is completely useless? Of course not? Am I claiming that there are not engineers that do perform all sorts of calculations? Of course not. Don't straw-man my position. My emphasis is on the vast number of unknowns and variables that go into a real-world assessment of a climbing anchor. Is that head REALLY good for 800Lbs? What are the odds of it? And so on. It IS ridiculous to think that the reliability could be achieved that would make the "negligible advantage" tangible in such admittedly sketchy situations. The more pressing the need to decide one way or the other on this question, the more pressing is the measure of unreliability. Engineering doesn't even touch, much less solve, that problem. My only point.
Do I find such discussions themselves useless? No, because a "seat of the pants" understanding derives from SOME measure of thinking about such things. Our intuitions are informed by background knowledge, which is how we can come to an intuitive notion that a placement will or won't hold a fall. So, such discussions are useful in educating all of our intuitions. However, that usefulness does not (imho) translate into providing a useful answer to the topic question of this thread.
The way to minimize human fallibility is to "back it up," but that is the very thing that is denied by the theoretical scenarios suggested as reasons to not lead-clip a placement. At the end of the anchor spectrum this thread is discussing the questions of human fallibility and lack of data are most pressing. Again, the theoretical discussion does not really address the actual topic question of this thread. Does that make it useless? Again, no. As I have said, no. But the usefulness is (imho) not applicable to the topic question.
Now to your three points:
(1) And we will forever lack a definitive answer.
(2) That model seems WORSE to me, not better, for addressing the force-transference issue. By catching the leader on the harness, at least you've got the belayer thrashing around (which actually helps a lot), his body compressing in the harness (which also helps), and so on. On the direct-to-anchor model, the forces go straight to the anchor without benefiting from all of the above "dynamic" aspects of a belayer. But, again, this just makes my point about the "fine" details here that just don't really translate into making an actual difference. No accident report is going to say, "The team died because, unfortunately, the belayer was too ignorant to catch the falling leader onto his harness. His decision to catch the leader with the anchor instead cost the team their lives. If only climbers would read and understand the engineering!"
(3) Is your problem with the word "always" in this context? If so, then I would respond that just because you can use the word "semantics" does not indicate that you understand the underlying logic. If you like, I will produce a mathematical induction (a form of deduction) for you demonstrating that my claim is in fact logically sustainable and correct. Furthermore, I'm baffled by your last sentence. It seems to me that you are making MY point: the whole situation as described is a mess, and the idea that the topic question is really the one that matters in such a situation is a red-herring question. In such a situation, you have much more important and practically-useful things to consider than whether or not to lead-clip an anchor placement.
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dirtineye
Trad climber
the south
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Dec 12, 2008 - 05:07pm PT
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Madbolter1, just so you know, yes, mathematicians and scientists DO have a problem with words like "always", and "every", and other absolute terminology, when it is used improperly.
Just one more tip-- before you really get into a donnybrook with Rgold about this stuff, you'd better have your act together.
The modeling these guys have done is important. If you can find something wrong with it, fine, point out the error! Otherwise...
Oh and back in the says before I had all this trouble, I used to look at mist distribution along the interstate and ponder modeling it with a system of partial DE, so, yeah people do that sort of thing, and there are a lot more of em than you might realize.
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Jaybro
Social climber
wuz real!
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Dec 12, 2008 - 05:20pm PT
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Would you Ever, climb with someone who doesn't do a sort of Clif notes version of that analysis on every single belay? -assuming swapping leads or at least belaying in possibly dicey situations.ie that the other partner is in a position to make decisions, not a n00b client or something.
I wouldn't, either.
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rgold
Trad climber
Poughkeepsie, NY
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Topic Author's Reply - Dec 12, 2008 - 06:45pm PT
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MB wrote, "Am I claiming that this discussion is completely useless? Of course not? Am I claiming that there are not engineers that do perform all sorts of calculations? Of course not. Don't straw-man my position."
You coulda fooled me. As for straw-manning, what is that entire paragraph of dumb pseudo-calculation? Who ever said climbers were making calculations at their belay stations? Let he who is without straw-man sin cast the first stone!
MB wrote, "My emphasis is on the vast number of unknowns and variables that go into a real-world assessment of a climbing anchor...It IS ridiculous to think that the reliability could be achieved that would make the "negligible advantage" tangible in such admittedly sketchy situations. The more pressing the need to decide one way or the other on this question, the more pressing is the measure of unreliability. Engineering doesn't even touch, much less solve, that problem. My only point"
To my perhaps insensitive ears, you have changed your tune. You now seem to be saying that there are so many variables and unknowns that it is impossible for the belayer to reliably judge an anchor, and that the degree of unreliability in belayer judgement increases as the anchor itself becomes increasingly suspect. But if the belayer cannot make reliable judgements, then an engineered solution that protects the anchor, independent of the belayer's potentially faulty analysis, seems to me to be even more desirable, not less. (P.S. I am not an engineer!) Secondly, it is you who have said not clipping provides a negligible advantage, not me.
MB wrote, "Do I find such discussions themselves useless? No, because a "seat of the pants" understanding derives from SOME measure of thinking about such things. Our intuitions are informed by background knowledge, which is how we can come to an intuitive notion that a placement will or won't hold a fall. So, such discussions are useful in educating all of our intuitions. However, that usefulness does not (imho) translate into providing a useful answer to the topic question of this thread."
I agree with you about all of this except that I haven't myself arrived at final judgement on the utility of the answer, and most humbly suggest that you may be premature in your dismissal.
MB wrote, "The way to minimize human fallibility is to "back it up," but that is the very thing that is denied by the theoretical scenarios suggested as reasons to not lead-clip a placement.
If by backing it up you mean placing an independent good piece for the leader, I think everyone agrees with that. In the absence of such a piece, or in the presence of the failure of such a piece, backing up isn't available in the anchor discussion. Clipping the anchor with the lead rope certainly doesn't back it up. So, in the absence of back-ups, isn't it reasonable to ask, "what options will stress the anchor the least?"
MB wrote, "That model seems WORSE to me, not better, for addressing the force-transference issue. By catching the leader on the harness, at least you've got the belayer thrashing around (which actually helps a lot), his body compressing in the harness (which also helps), and so on. On the direct-to-anchor model, the forces go straight to the anchor without benefiting from all of the above "dynamic" aspects of a belayer."
Under equivalent belayer behavior, the anchor gets a higher load from redirection then it does from the direct (belayer mediated) connection, once the break-even point has been passed by the leader. This makes it an interesting and useful theoretical question to ascertain just how far up that break-even point is. Such questions were the focus of the theoretical discussion you have heaped so much scorn upon.
The reason the direct connection might be better than inserting the harness as a critical link in the belay chain is that, as John pointed out, the latter approach might turn the belayer into a second falling object whose fall energy has to be absorbed by the tie-in, and this will raise the load on the anchor.
In any case, as far as the clip/no clip question goes, objecting to the direct vs. indirect belayer connection is irrelevant. Whatever method you use only has to be better than a redirected belay to be significant. So if the direct connection proves significant, your argument simply indicates that the indirect connection would give even better results, rather than somehow constituting a worse model as you suggest.
MB wrote, "Is your problem with the word "always" in this context? If so, then I would respond that just because you can use the word "semantics" does not indicate that you understand the underlying logic."
The word "semantics" belongs to the study of linguistics, so using it does not bear in one way or the other on my logical competence. My sin, for which I apologize, is in being too logical, rather than in failing to understand anything about some unspecified underlying logic. "Always" means without exception. You seriously suggest that there is absolutely never in any case in the past, present, or possibly infinite future that would constitute an exception to your claim? Really?
MB wrote, If you like, I will produce a mathematical induction (a form of deduction) for you demonstrating that my claim is in fact logically sustainable and correct."
I am most interested in seeing a proof of your claim by mathematical induction, and await its appearance.
MB wrote, "Furthermore, I'm baffled by your last sentence. It seems to me that you are making MY point: the whole situation as described is a mess, and the idea that the topic question is really the one that matters in such a situation is a red-herring question."
I thought your point was that if the anchor is good, why not clip a piece and if the anchor is bad, then you should (and ALWAYS would be able to) find an alternative. My point was if the belayer misjudges, then they fail to seek the alternative when they need to. How does this make your point?
As for the topic question (as opposed to the method of answering it) being a red-herring in such situations, this is certainly a position one might take. The term does have the connotation that the poser of the question intentionally means to mislead the audience by shifting attention from the real point, and I doubt you meant that. (Ho, ho, more semantics, eh?) If you had simply said earlier that the question posed as the topic of the thread was irrelevant to what "matters," then perhaps we wouldn't have ended up typing all this crap!
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madbolter1
Big Wall climber
Walla Walla, WA
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Dec 12, 2008 - 06:49pm PT
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Having a Ph.D. in philosophy myself, with a significant emphasis in logic, including mathematical logic, I too dislike uses of a word like "never" and "always," when, as dirtineye pointed out, "it is used improperly." However, I did not use a word "improperly." This is a stupid point to argue about however. The real issue is my supposed need to "have my act together."
Wow, are these engineer types really THAT defensive? All I have stated so far is that all the engineering talk really doesn't address the real-world implications of the TOPIC QUESTION of this thread. You guys can set up and knock down all the straw men of that point you like, if that makes you feel any better.
Jaybro, put these two sentences of mine together, and let's see what you get: "Almost all of us do a vague assessment of our anchors. My point is that the FINE theoretical points really don't do much to inform such a decision with ANY reliability. In the real world we simply rate anchors from bomber to sh|t, most far closer to the bomber end of the scale." And: "Do I find such discussions themselves useless? No, because a 'seat of the pants' understanding derives from SOME measure of thinking about such things."
Now, tell me how you get from those sentences to the (straw man) idea that I am claiming ANYTHING like that I'm advocating climbing with a partner "who doesn't do a sort of Clif [sic] notes version of that analysis on every single belay."
I'm gonna say it really... really...
really
slowly
now:
In the sort of scenario...
you need to imagine...
for the TOPIC QUESTION to even be interesting...
all this engineering talk...
simply does not...
reliably...
inform the answer to the TOPIC QUESTION.
Believe whatever you want, set up anchors however you want, I'll always find a way to set up a strong enough anchor that I can lead-clip at least one placement. Have as much fun with the theory as you want, and I'm NOT dissing that, but them's the real-world facts.
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Karl Baba
Trad climber
Yosemite, Ca
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Dec 12, 2008 - 07:06pm PT
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Rgold wrote
"(2) The leader fall, as explained in Chris Harmston's rec.climbing post years ago, should not be caught on the harness. It is essentially caught on the anchor, ideally with a some mitigating resistance from the belayer, but without the force-multiplying pulley effect at the anchor one gets by clipping it. "
I have to remind the thread that any benefit from avoiding the pulley effect at the anchor is only maintained if the belayer manages to keep his own weight off the anchor while catching the factor 2 fall through the vehicle of his harness setup. That's a tall order and Jroe's calculations show that if the belayer gets swept off his feet, the forces could actually be worse as the belayer becomes a faller as well.
Not be mention the "escape the belay" difficulties, which should only be discounted with evidence.
peace
Karl
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Largo
Sport climber
Venice, Ca
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Dec 12, 2008 - 07:43pm PT
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Madbolter wrote: " I'll always find a way to set up a strong enough anchor that I can lead-clip at least one placement."
The "always" tells volumes about Madbolter's experience, or his penchant to overestimate the robustness of his anchors. I don't know a single experienced trad climber who doesn't have multiple stories about that sketchy anchor on (fill in the blank).
That much said, the "variables" Madbolter and others mention pertain to the security of the primary placements in an anchor array. Indeed, these vary so much, placement to placement, that it's ludicrous to generalize much about how little or how much this or that cam or pin might hold. Not so with rigging systems and protocols, which is what we are discussing here. You can set up a three or four piece anchor in the lab and reliably test which rigging system and what protocol will place the least load on the anchor, no matter if the placemets are A4 or A1.
JL
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dirtineye
Trad climber
the south
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Dec 12, 2008 - 08:12pm PT
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Degree in philosophy eh?
We can stop right there, LOL.
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madbolter1
Big Wall climber
Walla Walla, WA
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Dec 12, 2008 - 08:13pm PT
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rgold, you're starting to type lengthy tomes like I do. Bravo.
Now I'm not sure exactly WHAT you are advocating. At first I thought you were advocating that the engineering talk in this thread is directly and immediately applicable to real-world anchor situations. If that is what you were claiming (my impression), then my little anchor-calculation scenario was most certainly not a straw-man. Just as I pointed out with it, it is ridiculous to think that anybody is going to perform such feats of engineering analysis AT the anchor.
But, from your last post, it seems that we are closer in our view than might initially appear. Now you seem to be saying that the theoretical talk is only intended to inform general thinking or intuitions about anchors, with very limited applicability to real-world situations. If so, then I agree.
But you also seem to say that there is very direct applicability insofar as "protecting the anchor" (and thereby increasing survival odds, which is what this thread is about) is something that can offset epistemic shortcomings in all situations: "If the belayer cannot make reliable judgements, [sic] then an engineered solution that protects the anchor, independent of the belayer's potentially faulty analysis, seems to me to be even more desirable, not less." If I take your meaning correctly, then we continue to disagree. That is a topic that, it seems to me, is worth discussing.
I also think you are confused about the relations between linguistics and logic, but I really don't want to head down that tangent, since most people won't give a rip about it, and those sorts of issues are good only for verbal sparring in this context (a big waste of time). So, I say this only to indicate that I don't agree but don't intend to argue at that level.
You say, "So if the direct connection proves significant, your argument simply indicates that the indirect connection would give even better results, rather than somehow constituting a worse model as you suggest." I respond, "worse" relative to what? I'm confused now (story of my life). It seems that now we have at least three different connection possibilities on the table, and my "even worse" claim concerned only two of them: belayer catches the falling leader on the anchor with no redirection, and belayer catches the falling leader on his harness with no redirection. Properly set up, I think that the first is worse than the second (there have been empirical tests to indicate this). But that is beside the (main) point.
I have not asserted that catching the leader on the harness IS an advantage. If you reread my statement, you will see that it is hypothetical. I'm saying the even if you grant that there is some advantage (of which I remain unconvinced), that it is an insurmountable problem to know when it is best to employ that slight advantage (if there be one). I certainly would not choose to catch all leaders falling past the anchor onto my harness just to "protect the anchor" because there is (might be) some small advantage to that. As this thread has repeatedly asserted, that advantage (if there be one) is really only significant in a tiny subset of really-sketchy-anchor cases. And my response to THAT idea has been to say that in THOSE cases you should put your energies elsewhere to create an anchor that does not any longer remain one of the really-sketchy-anchor cases. AND I have said that it is ALWAYS possible to find a better alternative than to lead above an anchor that is so sketchy that this discussion could find any real-world application.
Regarding "always," this is a silly point to pick on, but perhaps cashing this out will help to make my overarching point. If I need to formalize this, then I'll find some time to do that next week. For now, here is an informal version. I think this should be sufficient.
1) I define a "better alternative" to mean an alternative that increases the cumulative survival odds for the members of the climbing party that are huddled grimly at a severely sketchy anchor.
2) I note that by the very definition of this topic, not sending someone up on lead above the sketchy anchor is prima facie a "better alternative" than sending someone up on lead. "Protecting the anchor" is prima facie best accomplished by not leading above it. In the absence of objective dangers, the prima facie case is made; it is a better alternative to not lead above the anchor: Q.E.D.
3) I note that in cases where there are objective dangers, either the odds for the party are better if they sit tight, or the odds are better if they move.
4) In the case where the odds are better if the party sits tight, it is a better alternative for them to sit tight. Q.E.D.
5) In the case where the odds are better if the party moves, then either the odds are better if someone leads up, or the odds are better if the party moves in some other direction.
6) In the case where the odds are better for the party to rappel down, it is a better alternative that the party rappels down. Q.E.D.
7) In the case where the odds are better for the party to move to the side, it is a better alternative for the party to move to the side. Q.E.D.
8) In the case where the odds are better for someone to lead up, either the party possesses additional useful protection gear, or it does not possess such gear.
9) In the case where the party possesses additional useful protection gear, that gear can be used to improve the anchor. Improving the anchor is a better alternative. Q.E.D.
10) In the case where the party does not possess additional useful protection gear, either the party could/should have possessed such gear or it could not have.
11) In the case where the party does not possess additional protection gear, but could/should have possessed such gear, it is a better alternative for the party to possess such gear. Q.E.D.
12) In the case where the party does not possess additional protection gear and could not have possessed additional protection gear, it is a better alternative for one person to risk life than for all persons to risk life. The leader should lead above the anchor with no belay. An unbelayed leader is a better alternative. Q.E.D.
You should be getting the point. The number of dichotomies is not infinite, and you can run them down. (Since we're not dealing with infinities, this is not a true 'mathematical induction,' although it borrows much from that form of argumentation.) Pick a scenario, and it is possible to construct a "better alternative" to a belayed leader risking impact onto the sketchy anchor and taking everybody out with him. If the risks to the party are so high as to provide real-world motivation for this discussion, then there are ALWAYS "better alternatives" than to risk the leader impacting that anchor.
Of course, we can debate if my definition of "better" is the right one, but survival of the party seems to be the whole point to this discussion thread; so I think I can't be far off on that point. Besides, such further discussion doesn't threaten my use of the word "always."
One could talk about how there are other interests besides survival, such as the commitment to climb. In that case I will respond that it is a better alternative to add a bolt to the anchor and keep climbing.
If one says that we're only interested in situations that don't violate "ethical considerations," then I say that in this case "ethical considerations" have trumped survival considerations, which is not how this thread's question was cast.
Now, it might be an interesting discussion to talk about the topic question in the context of a sort of hyper-constrained thought-experiment where survival is not the primary consideration, so that bolts, rappelling, and other alternatives are ruled out in advance. But then I will note that THAT discussion will be purely theoretical and have nothing to do with real-world considerations.
Which was my point from the beginning.
This is NOT to "heap scorn" upon this discussion. My point is and has always been that the theory discussed here has little real-world application (and what application it has serves the limited, but useful, purpose of informing our intuitions), and none of it affects my decision to lead-clip every real-world anchor.
I'm gone for the weekend at this point.
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madbolter1
Big Wall climber
Walla Walla, WA
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Dec 12, 2008 - 08:21pm PT
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So, John, why the personal attack?
Perhaps you don't remember that it was said of one of the Lowes (I don't remember which one) that he could construct a bombproof anchor in a pile of sand, or some such thing. I would have to look up the quote, but I read it and was impressed by it as a young man. Consequently, I spent many years learning how to construct reliable anchors in all sorts of sketchy situations. We all can put in that time and practice, and exercise the good judgment, to avoid sketchy anchors.
Or perhaps you are suggesting that it SHOULD be a part of every "good" climber's resume that they lacked the skill and judgment to construct good anchors in some situations. If so, then I simply disagree. As you know (or should if you are going to make such statements), I did the fifth ascent of the Sea when it was still hard and still had a legitimate RURP anchor. So, I'm not sure what is the basis of your jibe. There's no call for personal attacks.
It is nice to see that you agree with my main point, btw.
Have a good weekend.
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JohnRoe
Trad climber
State College, PA
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Dec 12, 2008 - 08:37pm PT
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Karl: "That's a tall order and Jroe's calculations show that if the belayer gets swept off his feet, the forces could actually be worse as the belayer becomes a faller as well."
Well, that was a result of calculations based on some simple theory (linear and undamped response, climbers as point masses). IMHO, the shorter and stiffer the tie-in, the less useful this simplified theory is likely to be. Karl pointed out elsewhere that the % extensions it produces are quite extreme.
So right now I'd prefer to say that the calculations "suggest" rather than "show" the possibility that the moving belayer scenario significantly adds to the anchor load.
Peace
JohnR
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Karl Baba
Trad climber
Yosemite, Ca
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Dec 12, 2008 - 08:54pm PT
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Jroe wrote
"So right now I'd prefer to say that the calculations "suggest" rather than "show" the possibility that the moving belayer scenario significantly adds to the anchor load. "
Definitely fair enough. In fact, I think the word "Suggest" should apply to much of what is written by everyone in the this thread until real world test unveil the factors (or at least quantify the difference between theory and reality) that the math hasn't accounted for.
What would really be fun would be to go to a swag crag and have a "logger's jamboree" where climbers choose their belay (with some bomber backup) and take a bunch of gnarly factor two falls on some retired ropes)
Peace
Karl
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rgold
Trad climber
Poughkeepsie, NY
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Topic Author's Reply - Dec 12, 2008 - 09:19pm PT
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MB wrote, "rgold, you're starting to type lengthy tomes like I do. Bravo."
MB, I yield to no one in sheer verbosity. And I must say that anyone with a Ph.D. in Philosophy is my kind of man.
As for my view of theoretical calculations, your second characterization is close to what I think, although your insistence on "very limited" gives me some pause. I guess the degree of applicability may be in the mind of the beholder, so I won't quibble.
Unfortunately, we still disagree about what I would call optimal behavior in the face of uncertainty. I think the gist of the issue is in this statement of yours,
"I'm saying the even if you grant that there is some advantage (of which I remain unconvinced), that it is an insurmountable problem to know when it is best to employ that slight advantage (if there be one). I certainly would not choose to catch all leaders falling past the anchor onto my harness just to "protect the anchor" because there is (might be) some small advantage to that."
And I am saying, in the face of uncertainty, that my choice would be to embrace the small advantage.
As for the logico-linguistics, it best hammered out over endless cups of coffee or pints of beer, depending on your academic proclivities, rather than jointly creating a new 21st century sleep aid (from which, however, we might profit handsomely).
Have a wonderful weekend, come back safe and sound, and may you never encounter anything that could possibly be a subject for this thread.
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Largo
Sport climber
Venice, Ca
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Dec 12, 2008 - 10:12pm PT
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Madbolter wrote: "So, John, why the personal attack?"
No personal attack intended, and my bad if you took it that way. It's just that I don't believe for a second that an El Cap vet like you - or many others on this list - has always belayed from bomber anchors. Man, I remember doing an early ascent of the Shield and belaying and hauling from one buttonhead bolt with a "sleeve" hanger hand-placed over the mo fo. How could you have possibly escaped ALL such situations all these years?
Perhaps it's true - I never rule out the possibility that I'm totally full of sh#t - but it is strictly fantastic if so.
JL
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rgold
Trad climber
Poughkeepsie, NY
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Topic Author's Reply - Dec 13, 2008 - 02:32am PT
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Karl wrote, "I have to remind the thread that any benefit from avoiding the pulley effect at the anchor is only maintained if the belayer manages to keep his own weight off the anchor while catching the factor 2 fall through the vehicle of his harness setup. That's a tall order and Jroe's calculations show that if the belayer gets swept off his feet, the forces could actually be worse as the belayer becomes a faller as well.
In the system I described, it isn't necessarily a tall order at all for the belayer to keep from becoming a free-falling object. If the connection to the power point is two feet long, the belayer's anchor point will displace downward perhaps eight inches, a mere deep knee bend. This is exactly what happened when I caught a factor two fall---I ended up kneeling on the ledge.
And this deep knee bend is a lot better than what is in store for the belayer with a redirect who isn't also tied down. The belayer is going to be violently flung upward, according to JohnR's calculations: "After 372ms, the belay device gets sucked at high speed into the biner on the power point. I didn't attempt to write any equations for what happens after that :-)"
Add to this Mad Bolter's story about being flung six feet up from his hammock until his belay plate smacked into the anchor bolt. A belayer whose waist is three feet from the redirect is going to hit harder and will have less time to get their feeling hand out of the way of a serious mangling. It seems possible to me that the results could be worse for the belayer than the deep knee bend he gets to do in the factor two catch with the anchoring I described.
Morevover, we don't yet have any calculation for what happens in term of anchor load after the belayer hits the redirect. Is there a second peak? Can it be larger than the first peak?
Finally, if the belayer is not anchored down to avoid being slammed into the redirect biner, the anchor itself had better have a solid upward directional component, at least if it is a trad anchor with vertical placements, because otherwise the upward belayer impact could extract the anchor.
I've had a lot of experience BITD catching factor 1.5+ falls for practice using a weight, and I can guarantee that the belayer is going to be flung upward hard---I've experienced this first-hand over and over, and I would not want to be stopped by running into the anchor, nor would I have a lot of confidence in the belay surviving the experience. I'd think that loss of control is highly probable. Kudos to MB for hanging on!
So, if you are going to redirect, then the belayer really had better be tied down, and then we're back with the pulley effect loading of the anchor again...
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healyje
Trad climber
Portland, Oregon
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Dec 13, 2008 - 09:14pm PT
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To be honest, I'm more from the Edisonian school of engineering. And while the 'models' may set some useful constraints and boundaries around the problem space, I personally don't find them nearly as informative as simply catching these sorts of falls. Once you've done that a couple of times you get a pretty intrinsic feel for the forces involved which does inform in some significant ways that you then factor such a possibility into every belay.
For me that means I insert my body into the system to act as the principal buffer and cushion between a falling leader and my anchor if worst comes to worst. I have no doubt whatsoever about my ability to hold and control such falls directly off my harness, however punishing, and an anchor would have to be extremely stout before I'd hazard clipping it to spare myself the abuse.
Without the substantial dynamics inherent in having a human body directly in-line in the system, or when redirected through the anchor, I have no doubt the models get more accurate - and scary as far as I'm concerned. From my experience going au naturale, everything from sacrificial stancing, to rotating with the fall, to simply being 'crunched' hard relieves considerable amounts of force involved in [unfortunate] real world 'tests' - lots of little dynamics add up in very beneficial ways. But to make it all work, you really have to be actively working the small stuff, be hyper vigilant, and have your belay and stance pretty 'detailed' out on minute-by-minute basis.
In the end, I suspect this is definitely a case of 'to each his or her own' and probably no small amount of perceptions, adrenaline, and FUD influence the decision-making as well.
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WBraun
climber
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Dec 13, 2008 - 09:35pm PT
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Largo -- "Perhaps it's true - I never rule out the possibility that I'm totally full of sh#t - but it is strictly fantastic if so."
Ah so .... I know I'm full of sh#t, I take one every morning.
Now ... when second yells up to me and asks "Is belay Bomber?" while I'm anchored to the usual tiny twig, I yell back down ....
BOMBER man ......
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Tarbuster
climber
right here, right now
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Dec 13, 2008 - 09:46pm PT
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Should the leader clip the belay anchor?
Sure, as standard procedure, unless the anchor is crap, then the leader should instead clip the next solid piece of protection.
If the next piece of protection isn't solid, then the leader should not clip that either (WTF??!!??)
Or sometimes I don't clip the anchor if I'm not concerned that I might fall right away and if I also see that clipping the anchor is just going to cause unnecessary drag and implement a poor feed.
Lots of times I don't clip the anchor because I have determined that's not where the action is going to be.
That's my story and I'm sticking to it.
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madbolter1
Big Wall climber
Walla Walla, WA
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Dec 14, 2008 - 04:20am PT
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John, a class act, as always. Thanks. Such is the difficulty with "reading" people based upon a brief snippet of verbiage. My bad that I took it wrong. Thanks.
rgold, you too. Much appreciated.
Regarding the six-foot "launch," I take that to be a good thing, as it is akin to soloing with the anchor-end tied to a haul bag in the hope of introducing some "dynamic" action during a fall. I've gotta believe that launching a belayer absorbs a LOT of force and mitigates some of that 2 to 1 force on the power point.
But, I'm with tarbuster in the sense of just "having a story and sticking to it." Could be crap, but having been the launchee, all I can say is that I would rather have held the falls that way than onto my harness. I honestly can't imagine how horrendous that would have been. The forces involved are indescribable.
Oh, and: modern climbing ropes are BEYOND marvels of engineering! Kudos to those engineers!
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Steve Grossman
Trad climber
Seattle, WA
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Sep 19, 2009 - 05:47pm PT
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Overblown And Humorless Blather Bump!!! QED
Quintessentially Egotistical Dumbass that you are at the end of each sentence. QED
Does your course in logic enable you to cram two greenhorns, a half ton of crap and thirty nine days into anything resembling good or noble style? LOL
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RyanD
climber
Squamish
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Jan 26, 2015 - 09:53am PT
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Oh my.
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rgold
Trad climber
Poughkeepsie, NY
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Topic Author's Reply - Jan 26, 2015 - 05:34pm PT
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My goodness! We were young once.
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Majid_S
Mountain climber
Karkoekstan
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Jan 26, 2015 - 08:50pm PT
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If we do some serious FF2 drop test with live person on most trad anchors, I would wounder how many drops turn in to a Taco incident report.
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Lasti
Trad climber
Budapest
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Jan 27, 2015 - 07:36am PT
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Interesting read, a lot of very good points by some great minds with both the theoretical knowledge and real-life experience to get into a massive debate.
Clint wrote on the first page, following up on Tomcat and others:
To reiterate what others have said, you can drastically lengthen the belayer's connection to the anchor, when there is hard climbing immediately above the belay, and clip the belay with a screamer/load limiter. This is what Kelly and Bruce did when trying to lead p2 of Exodus on Middle Cathedral this past summer. Bruce connected to the anchor with about 20 feet of rope, so he hung well below the bolts.
This has been standard practice on German and Czech sandstone for ages. These places often have hanging belays (no deep knee bend) of a single ringbolt (a big one, but still...) and no "Jesus nut" option for a ways off the anchor.
The question remains: how much rope between the belayer and the anchor would mitigate the pulley effect?
Lasti
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sDawg
climber
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Jan 27, 2015 - 01:38pm PT
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Interesting physics lesson and no argument here with your logic. Personally, I like to believe my anchors are at least stronger than the average belayer's back and as a standard-issue 60kg belayer, I prefer upwards to downwards forces on my hips when catching a flyer 30-50% heavier than I am. I'd bet that when most climbers clip the anchor or a first piece from the belay, they're thinking more about keeping their belayer uninjured than preventing anchor failure.
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Gnome Ofthe Diabase
climber
Out Of Bed
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Jan 27, 2015 - 05:20pm PT
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The group reached no real concensus, but that what Clint said and was backed up,anadotaly,
was that by extending the belay, a far enough distance to provide the climber to opertunistically take advantage of the belay anchors as the first protection point, one could minimize the forces of the long fall on the short/no pro from the belay (yikes, just trying to summarize!)
Largo, opinined, that Under some circumstances he would choose to be anchored to a single point in the system and try to use the rest of a questionable anchor as pro
to reduce the forces that are generated in a fall that borders on a factor 2 force fall.
Largo' statement includes the modified 'would try to hold the fall off my waist'(a down ward pull off his waist)- this can be the hard part due to the chaotic nature of the belayer reaction to the forces,ie slammed into or up to the anchor. . .
I hope that, that is the right answer, Jebus
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jstan
climber
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Jan 27, 2015 - 08:28pm PT
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We have been exchanging perceptions here. How about looking at some data?
Gritstone climbers have published their techniques allowing use of marginal pro. They set the second up with their tie in above the belayer so that when there is a fall the belayer is pendulumed a long distance up into the air. As long as their tie in acts as a pendulum their mass can be made effectively less than their full weight. A dynamic belay where they can actually tune the belayer's effective mass to meet the requirements of the situation. All a matter of the angle. Now some measurements I made in 1971.
I dropped a 165# bag of shale forty feet in free fall, measured the total force on the top piece in two situations. One where the belay rope was tied directly to a big tree trunk and the second where I gave a waist belay and could be whipped around a couple of feet. When my motion provided dynamic response I measured a peak force of 500# on the top piece. With the rope tied directly to the tree I measured 1000#.
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rgold
Trad climber
Poughkeepsie, NY
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Topic Author's Reply - Jan 27, 2015 - 08:30pm PT
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There is no consensus. As with many things it depends, and in this case there are two aspects to depending. One aspect includes the objective considerations such as
How good is the anchor?
How close is the belayer to the anchor?
A second aspect has to do with the climber's approach to and philosophy about risk management. I'm not going to list specific items here to try to keep a lid on contention, but a reading of the thread reveals some genuine differences in how people think about these things.
Petzl and other belay-device manufacturers include warnings in their manuals that indicate that their devices cannot be counted on to stop a factor-2 fall from a waist belay. One of the reasons is that one has to know to use a different braking hand position, but another reason is that the amount of friction supplied by the device, especially with thin slippery ropes, may be inadequate. These manufacturers tend to assume the existence of bolted belays, as is more common in Europe than in this country, although we are catching up.
I've caught a UIAA-level fall (i.e. factor 1.7 ish) with a Petzl Reverso II on the harness. Well, not directly on the harness but rather clipped to the rope loop, as some Brits are fond of doing. (See http://www.ukclimbing.com/articles/page.php?id=1129. I learned it from Chris Harmston on rec.climbing many years ago.) The tie-in was fully tensioned so that the load went directly to the anchor, mediated by the stretch in the tie-in and a small amount of resistance from the legs. The catch was on a single strand of 8.5mm half rope and yet there was enough friction for me to hold the fall. I don't remember the rope slipping but had gloves on and so might not have noticed a small amount of slip, which probably happened.
I thought that the new group of assisted locking devices (not the Grigri) might be the answer to the problem of inadequate friction for high loads. But Jim Titt has done some tests that suggest the assisted locking devices have a substantial fall-off in braking power as the load goes up and may well be worse than, say, an ATC-XP. Anyone interested in those results can consult the Mountain Project donnybrook on the subject, but you'll need to be able to tolerate a very high level of static. http://www.mountainproject.com/v/edelrid-megajul-belay-device/109133730__1
There is no question that extending the belayer's tie-in will allow the anchor to be clipped yet loaded less critically in case a fall happens. In many ordinary climbing situations, it would make sense to build the belay anchor much higher than the belay ledge so that the leader could clip it and contemplate falling on it without producing maximal loads. This is utterly removed from the conventional approach to belay stance construction but, as I said, makes a lot of sense. Craig Connally suggests it for some situations in his vastly under-appreciated book The Mountaineering Handbook: Modern Tools and Techniques That Will Take You to the Top. http://www.amazon.com/The-Mountaineering-Handbook-Modern-Techniques/dp/0071430105, but I've seen no evidence that such an option is on the general climbing world's radar.
As for John's comments about lifting the belayer, there is little question that this provides lower loads than a totally static belay. But in a belay stance situation with the rope clipped through the anchor, lifting the belayer can have a host of adverse effects, as mentioned earlier in the thread. Tests by the Italian Alpine Club suggest that, as far as load reduction goes, just a little amount of lifting (I think less than a meter) contributes to load reduction on the top piece, after which there is no further advantage. So the message would be, if a down-anchor is employed, to not tension it but allow for some lifting (but not enough to let the belay collide with the clipped main anchor).
It is interesting in this regard that European practice---especially in Italy and Germany---seems to be evolving in the direction of belays for the leader directly on the anchor (assumed to be the typical two-bolt installation of course). The somewhat higher anchor loads are offset by a kindler gentler experience for the belayer. Belaying the leader directly off the anchor seems to be greeted in this country by shock, disbelief, and scorn, even when climbs are equipped with bolted anchors that would be up to the task. But then we still have absurd discussion about "equalizing" such anchors...
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Lorenzo
Trad climber
Oregon
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Jan 28, 2015 - 10:45am PT
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thought that the new group of assisted locking devices (not the Grigri) might be the answer to the problem of inadequate friction for high loads. But Jim Titt has done some tests that suggest the assisted locking devices have a substantial fall-off in braking power as the load goes up and may well be worse than, say, an ATC-XP. Anyone interested in those results can consult the Mountain Project donnybrook on the subject, but you'll need to be able to tolerate a very high level of static. http://www.mountainproject.com/v/edelrid-megajul-belay-device/109133730__1
Interesting link. Halfway through I was thinking " this is three hours of my life I'll never get back" but there is value there.
I'm a little puzzled by one thing. With the new generation of floss ropes one would think there would be a bit more attention paid to how devices worked with them. For multi pitch leading my partner and I have both preferred half/double ropes for decades. I have 8.2 ropes, my partner owns 7.8. We both use the ATC-XP, but are open to other solutions. Devices that only handle one rope aren't even in consideration and most devices aren't even offered as suitable for ropes that small.
I'm a bit puzzled why Jim Titt didn't even try the Microjul device In those size ranges but insisted on staying with the Megajul. ( I haven't yet tried either) Clearly, the larger device is not the device design best suited to them. The Microjul is designed for smaller ropes, and looks to be the only device that claims to work with ropes smaller than 7.7 mm. The best I can come up with is he owned one and not the other.
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rgold
Trad climber
Poughkeepsie, NY
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Topic Author's Reply - Jan 28, 2015 - 02:01pm PT
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I fully sympathize with the waste of your life.
Those tests addressed the lower limit claimed by the manufacturer. Another device (like the microjul) might work better, but the point was to understand the manufacturer's claims for a given device.
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Don Paul
Big Wall climber
Denver, Colorado
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Jan 28, 2015 - 02:35pm PT
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I remember climbing with someone who clipped the anchor, then had me (the belayer) unclip it after he clipped his first piece. Must have already known all this.
Glad to see other people climbing on double ropes. I like them too but thought they were out of style.
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Lorenzo
Trad climber
Oregon
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Jan 28, 2015 - 02:57pm PT
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If his first piece had pulled, do you think he'd have had you reclip?
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Don Paul
Big Wall climber
Denver, Colorado
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Jan 28, 2015 - 03:19pm PT
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^ dunno. I would rather catch a fall off the anchor, than directly on my harness, though.
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WBraun
climber
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Jan 28, 2015 - 04:38pm PT
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Should the leader clip the belay anchor?
No .... just stand there drooling and start belaying without clipping into or using any anchor.
Isn't that how it's done?
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Lorenzo
Trad climber
Oregon
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Jan 28, 2015 - 05:06pm PT
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If the partner drools on your rope, no.
Not cool.
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drizzle123
Trad climber
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Jul 20, 2017 - 05:21am PT
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rgold,
Could you please show the maths for your break-even point calculation? I can't figure it out.
It seems your model would undermine the Chariot Belay method, so what method do you use to mitigate things? Leading through to the first piece of the next pitch?
What do I mean by mitigate things? I guess there are two considerations, fall factor and peak force on anchor. I don't really understand how they are related or which takes priority, but maybe your maths will clear that up.
Thanks for all your informative posts!
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rgold
Trad climber
Poughkeepsie, NY
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Topic Author's Reply - Jul 20, 2017 - 08:40am PT
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Drizzle, in a few days I'm off to the Tetons for three weeks and might not be able to reconstitute those calculations until I get back, as I have many things that need doing before I leave. In any case they can't be posted here; I'll send them via Supertopo email. If you don't get anything by early September, best to message me, as I may simply have forgotten.
The connection between the quantities you mentioned is that, in the classical rope model, the fall factor determines the rope tension and the rope tension determines the top anchor load, which is approximately 70% higher than the rope tension.
If the leader falls on the anchor, then as has been noted several times already, the only mitigation strategy is to decrease the fall factor by moving the belayer further away from the anchor. (The fall factor is decreased because moving the belayer adds rope to the fall-catching system and so makes the "L" in H/L larger while the "H" remains the same.)
Something that hasn't been part of the discussion is that the dependence on the fall factor ends as soon as the rope starts to slip through the belay device (if a device that allows such slippage is used). Once that happens, it is the length of the fall that is critical and not the fall factor, and what this means is that catching short FF2 falls is going to be "easier" than catching long FF2 falls if your belay method allows for rope slippage and you are equipped to handle it.
And speaking of rope slippage, there are two possible phases. In the first phase, the rope slips through the device but not through the belayer's hand; the brake hand is pulled to the device while gripping the rope. In the second phase, once the belayer's hand has no further opportunity to travel, the rope slips through the belayer's hand. It is possible that the first phase slippage absorbs enough fall energy to stop the fall, indeed I think this happens a fair amount, and when it does the belayer reports no rope slippage because no rope ran through their hand.
This suggests a belay habit which I rarely see in the field, which is keeping the brake hand as far away from the device as possible, say down by the hip. My unscientific observation is that most belayers have their braking hand almost on top of the device, which means they get no phase-one advantage for a severe fall.
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guyman
Social climber
Moorpark, CA.
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Jul 20, 2017 - 08:53am PT
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rgold.... have fun in the Tetons.
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drizzle123
Trad climber
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Jul 20, 2017 - 11:56am PT
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rgold,
I found your paper on standard equation for impact force. Using the parameters you laid out earlier, and the tension equation from that paper, I calculated a break even point at .596 fall factor when clipping the anchor (just solving for r assuming the peak anchor loads are equal across both situation). That's an even more dire outlook for clipping the anchor.
Anyway, I really appreciate your work, particularly the revelation that a factor 0 fall imparts 2x body weight on an anchor. That was very surprising!
My takeaway is to focus more on the eventuality of ff2, and less on marginal methods of avoidance.
Thanks a ton!
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