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le_bruce
climber
Oakland: what's not to love?
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Mar 10, 2010 - 04:27pm PT
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Chiloe, don't sweat the criticism of your anchor and don't fall into the trap of defending it here. Any picture of any anchor in a climbing forum always brings out the 'experts' and their opinions.
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August West
Trad climber
Where the wind blows strange
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Mar 10, 2010 - 04:35pm PT
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On the back of my harness, I keep a sling that has two, very light, locking biners on it and I usualy I have an additional two very light locking biners.
For a two bolt belay, not leading in blocks, I would clip in to one bolt with the locking sling and clove hitch the rope to the other bolt with a free locking biner, and cinch it up if I want to hang/lean against the anchor. If the bolts were too high to clip in straight with a sling, I would probably clove hitch the rope (in series) to the bolts.
For leading in blocks, I would first clip the two lockers to the bolts and then clip into the lockers. That way, when my partner gets to the belay, he can clip into the lockers and I can still easily unclip. Essentially, the light lockers become oversized bolt hangers. For leading in blocks, we flip the rope. Even at an awkward belay where the rope is flaked over a sling, we have gotten good enough to flip it without having problems during the next lead.
For a natural anchor where each piece is very good, I would directly sling into one piece and clove hitch the rope to the other two. Modifying it as needed for less bomber pro and block leads.
I belay off the harness unless rope management makes it easier to belay off the anchor.
I expect to go my whole climbing career without ever having to escape the belay. If it ever comes up, I will take the micro knife that I always climb with, and spend 10 seconds or so cutting myself free.
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Chiloe
Trad climber
Lee, NH
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Mar 10, 2010 - 04:38pm PT
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Yer right of course. If the anchor looks funny, good or bad, sometimes I'll shoot it. Here are a couple where the leader finished the pitch with nothing left but the rope and one locker:
Or just the rope, one biner and a sling:
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guyman
Trad climber
Moorpark, CA.
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Mar 10, 2010 - 04:46pm PT
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I think it is very important to load cams with your body weight.
Kris Solem relayed this tragic story to me.
In the early to mid eighties, in the white Mts of NY, a complete anchor failure occurred.
It was a two person party, the belay was on a good ledge. The pro was 3 cams (friends 1-2 size) in a parallel crack, running vertically. The next pitch involved some 5.8 OW ,very steep, going directly above the belay with zero pro for about 25 feet.
When the bodies were examined, they figured out that the belayer was standing on the ledge, clipped into the anchor with slings and belaying off his harness with a stich plate. The slings were sort of long-- to long to have been under his body weight. The leader had climbed about 20 feet and placed no protection when he fell. So now you have a 40 footer on to the belay, it must have created some huge forces. The cams pulled right out! Kris says he looked at the little scratch marks the cams created as they blew.
I always remember this tale. When I am setting up I put my weight on the anchor cams so the lobes are tight.
I always remember the two poor fellows who pulled a cam anchor and went south on Taquitz, I forget the climb, super pooper? I have never read any good explanation for that one.
And I never belay off of the anchor, looks pretty sketchy to me, always off of my harness.
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mongrel
Trad climber
Truckee, CA
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Mar 10, 2010 - 04:56pm PT
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Pate and Jim E: Then please explain WHY it's a myth so the rest of us can understand and be enlightened and stop perpetuating that myth. But the explanation needs to make sense. The verbiage quoted just above says, "...when/if a piece blows there is further reduction."...[implication: of the "initial impact on the anchor"] Wait, so when pieces blow there's LESS force on the remaining piece or pieces? That doesn't sound right, so I'm misinterpreting something. Otherwise, something must have accelerated (or work been done) for that to be the case.
I'd be happy to be pried loose from the shock-load myth, but just being told it's a myth isn't quite enough info. It's natural enough to want to hear a little more explanation (or else I wanna know who Jim E works for and buy some other brand of rope!). Just kidding, but I would like to hear more.
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Jim E
climber
away
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Mar 10, 2010 - 05:03pm PT
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mongrel,
I'll take a look around for the data I gathered during the anchor work for Long's book. I'm about done for the day so won't be able to look for it until tomorrow... even then I may not have time but will try.
One of my lab computers was DOA when we moved to a new facility a few years ago, I'm hoping the data wasn't in that one. I might have hard data kicking around, too.
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aa-lex
climber
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Topic Author's Reply - Mar 10, 2010 - 05:05pm PT
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Just curious why some people feel belaying off the anchor is sketchy. Seems like if the anchor is bomber, then why would it be an issue. If the anchor is suspect and it's really important to absorb some energy using my body then it would help to belay off myself but I feel like an auto blocked anchor belay off a great anchor is a good way to belay.
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rgold
Trad climber
Poughkeepsie, NY
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Mar 10, 2010 - 05:09pm PT
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Well, we seemed to be doomed to reiterate on this subject (not that there is anything necessarily wrong with that). Before beginning, I feel obliged to defend against what I think is a fallacious criticism: that all this complication slows things down to a crawl. Personally, I'm not arguing for complicated set-ups; I have no interest in the various "olettes" that have been proposed. But I reject the contention that somehow knowing and understanding a lot is bad. Knowledge gives you options, and it enables you to make informed choices about the risks you are undertaking.
Stats on anchor failure: I've never seen anything official. In fifty years of climbing, I've heard of a few more than five, so maybe one every eight years or so. Not very likely, but of course when it happens you don't want it to be you or anyone you know. Remember that the unlikelihood of anchor failure is confounded with the unlikelihood of leader falls directly onto the anchor; we surely have no idea of what the anchor failure rate is.
Although not mentioned much yet, I think even the most dedicated rope-anchorers agree that when you get on a wall and have all kinds of crap hanging from your anchor, a cordelette and its master point are the way to go.
For cragging and mostly free climbs, even long ones, I just use the rope unless I am in some kind of "guiding" mode in which I'm doing all the leading and my partner is not an equal, in which case a cordelette seems advantageous.
As for myths, the real myth is equalization. Even various sliding systems are hindered, perhaps decisively, by friction. Equalizing two pieces with a sliding thing and clipping directly to a third is not going to equalize any better, on average, than some equivalent fixed-leg setup. The convenience of rigging might still be decisive in such a case, and such a set-up may, in some situations, cope better with forces that are not in the expected direction.
A second myth, unfortunately, is the rapidly propagating myth that shock-loading is a myth. Of course, shock-loading is an undefined term, but what people typically mean is that extension in an anchor doesn't matter, and they cite the Sterling tests quoted by Largo. Unfortunately, the implementation of those tests was flawed---their negative conclusion was predictable ahead of time---and they actually shed no light on the real issue. Here are some things I think it safe to assert:
(1) In principle, anchor extension could be catastrophic.
(2) How serious it is in practice will depend, I believe, roughly on the ratio of anchor extension to belayer tie-in length (at least if the anchor has been constructed from relatively static materials). This is an H/L ratio for fall arrests by climbing ropes, and if it is big (i.e. short tie-in compared to anchor extension, then I'll go out on a fairly sturdy limb and claim that high anchor loads are guaranteed.
The reason this wasn't detected in the Sterling tests is that they were set up in such a way that the relevant ratio was very small, perhaps in part because there was no weight in the test playing the role of the belayer. (*)
What does this mean practically? I'd say that if your belay anchor includes potentially extending components, then you should try to rig the longest (rope!) tie-in your stance will accommodate. This is all situational, as is everything in climbing, but it is easy to think about and easy to implement if the opportunity exists.
By the way, connecting yourself to an anchor rigged with static material by way of some sort of tether rather than the rope means that you will be applying the largest possible load to the anchor if a bad situation happens. Given the speed with which one can tie in with the rope itself, I find it hard to imagine that tethering-in the belayer could ever be a very intelligent idea, even in the context of a speed ascent.
Most of the time, the ultimate security of the belay anchor is a hypothetical consideration that will never be tested. But if you are forced to build a belay anchor with pieces that are not highly reliable---surely the best example is an anchor built with small cams, and I'll leave the definition of "small" to the reader but would propose sub-purple camalot size---then I think the best thing to attempt is a four-piece doubly-equalized anchor (2 sliding X's or equivalent equalized with a sliding X). You can make one of these easily and very quickly, although using up six carabiners in addition to the powerpoint locker might be a high price to pay. This set-up has the best chance of equalizing the load and so keeping everything in place. I wouldn't use a three-point anchor with questionable gear because I don't think there is any decent way to rig one that isn't likely to put half the total load on one of the anchor pieces.
Ok, I've gone on for too long now. Time to go home.
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(*) I hope these comments are not taken as criticism of those who gave freely of their time and efforts. I'm only saying, in retrospect, that the tests don't actually test the belay-anchor scenarios that matter. I should add further that I read an advance copy of Largo's text and did not spot this problem at the time, so any inferred criticism falls on my shoulders as much as on anyone elses.
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Chiloe
Trad climber
Lee, NH
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Mar 10, 2010 - 05:12pm PT
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What's that knot at the bottom on the left side of the second anchor Chiloe?
Just a loosely-tied overhand knot. I tend to use overhands in anchor setups too, for tying into a piece that is out of line with the main direction of pull. The overhand loop serves like a runner out to the side piece, but its knot should have the fine properties of a Euro Death Knot if pulled directly. (But only if tied properly, of course.)
Really, I make up each anchor on the spot. There's a time and a place where this made perfect sense:
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Morgan
Trad climber
East Coast
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Mar 10, 2010 - 06:58pm PT
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Anchor Force Continuum (belaying the second)
I've always understood the following:
When the anchors are sketchy, don't redirect the belay off the anchors, belay off the harness.
Direct belay off the anchor. It's strong because the anchor only has to absorb the force of the second in the event of a fall. If it's a sling belay the leader's weight may already be on the anchor.
Redirected belay. This is ideal if the second is following a traverse and convenient when swinging leads. Some good shock absorbing because the leader can often move slightly upward toward the anchor. A redirected belay puts more force on the anchor because it bears the weight of both the second and the belayer.
For belaying the leader, it seems the redirected belay is the belay of choice, even though the direct belay is popular in Europe. By definition, anything else is a factor 2.
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Largo
Sport climber
The Big Wide Open Face
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Mar 10, 2010 - 07:29pm PT
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I think I might have looked at the entire subject of anchors about as much as anyone else out there. In reading 1,000s of pages of shite and writing two books on the subject, a few of my final conclusions are:
If you want totally bombproof anchors, you must stick with good rock.
Concentrate on setting solid primary placements, the actual nuts, cams and so forth in the anchor array. If two or more primary placements are bomber, the chances of the anchor failing approach zero.
Avoid rigging systems that feature the possiblity for huge extension. The value of equalization (never fully achieved) is usually overstated.
Understand about direction of pull/loading, and basic force vectors, and learn basic ways to safeguard against them.
Rig the anchor with the simpliest system possible, using as much nylon rigging gear (the rope) as is realistic.
Elaborate rigging systems (various "olette" arrays) are very rarely needed and often waste time. However, in extreme cases, these systems might be life savers, ergo they are worth knowing. 99% of the discussions per belay anchors are germane to about 1% of anchors you will encounter out there, when the primary placements are VERY poor and various SRENE and tricky rigging strategies are called on.
Anchors built in horizontal cracks are more likely to fail than those built in vertical cracks. A consideration.
Belay anchors rarely fail, not because climbers do such an outstanding job of anchor building, rather because true, factor 2 falls, or significant falls directly onto the belay anchor (other than slab skidders) are VERY infrequent.
Questionably, the most important single piece in the entire roped belay system is the "Jesus Nut," the first piece of pro off the belay. If Jesus is solid, the chance for sudden anchor failure is remote providing you have at least one decent primary placement.
Much of the concern about belay devices and where to put them and how to clip them off and to what and wherefore and how come - this is pretty much overstated since the old hip belays so rarely failed. They also provided another dynamic link in the anchor chain and while seeminly less reliable than modern techniques, they were in some cases more secure.
If you frequently climb where you anchor of to two side by side bolts (classic sport anchors), always carry a pre-rigged "Quad" and rig the anchor with this and this alone. Almost perfect equalization, super strength, instant and simple to rig, and super light and low profile.
Climb long enough and you'll likely run into the rare situation where you're not sure if the belay anchor can withstand a significant fall. You'll also run into routes where you're unsure if you can crank unprotected climbing directly off the belay. Do NOT, under any circumstances, try your luck with the previous two scenarios AT THE SAME TIME.
Put differently, if the anchor is sh#t, carry on only if you KNOW you can make it (and how can you?), and if a fall seems likely directly off the belay, make sure the anchor/protection/Jesus Nut is bomber. If the anchor is sh#t and you don't know if you can crank the climbing just above, your're truly "all in."
JL
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the Fet
climber
Tu-Tok-A-Nu-La
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Mar 10, 2010 - 08:24pm PT
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The problem I have with the "Jesus Nut" is they always vote Republican.
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pud
climber
Sportbikeville
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Mar 10, 2010 - 08:27pm PT
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I was hoping you'd put in your $.02 John.
Your knowledge on this subject taught me alot about things I thought I knew.
-w
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tolman_paul
Trad climber
Anchorage, AK
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Mar 10, 2010 - 08:30pm PT
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As to benefits of belaying off the harness vs. the anchor:
1) I have never been able to move rope as quickly and smoothly from a remote located belay device as I do when the belay device is right in front of me. You say so what, jerk, jerk, jerk, I'll catch up the second eventually. If you're not keeping up to your second, if he falls, he will generate a greater force with slack in the system then if the rope is taught, and that fall is directly on the anchor.
2) Adding stretch and give to the system is better than having a rigid system. Some of the force of the fall will be absorbed by the belayers bodie before forces are transmitted to the anchor.
3) Call me somewhat paranoid, but I prefer to put as little loading as possible on gear. You never know how good an anchor is until you load it, and for belay stances where the belayer will be able to catch a fall w/o loading the anchor, that's a good thing.
4) It's how I learned how to do it, it's how I've always done it, and sticking with systems and techniques you are familiar with is generally the best way to go. Add fatigue and changing weather into the equation, and you have added more potential for problems.
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HighTraverse
Trad climber
Bay Area
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Mar 10, 2010 - 10:04pm PT
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Avoid rigging systems that feature the possiblity for huge extension
OK, so I've climbed a long time, rigged many anchors and understand the physics of them (I'm a mechanical engineer). I've read Largo's book on anchors a few times.
I'm unfamiliar with the word "extension" used in two posts. Did I miss it in Largo's book?
I can guess what it means but will someone state what is meant?
Very useful discussion.
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HighTraverse
Trad climber
Bay Area
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Mar 10, 2010 - 10:25pm PT
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Thanks a lot. That's what I was guessing. And you show two very good examples.
When 1 piece of an equalized sliding anchor fails, the remaining anchor rigging will "extend" the anchor until the second piece is loaded.
So in some cases a cordalette rig has advantages, depending on the direction of load. If the load results in almost equal distance to the two anchors, when the taut one fails the extension will only be a few inches before the second is loaded. This results in a very small increase in kinetic energy from the extension. And the first anchor failure will have absorbed some kinetic energy. A sliding anchor point may have much greater extension and kinetic energy increase before the second anchor is truly loaded.
I believe every anchor has to be setup with consideration for all factors. There is no one easy solution. As John points out in his post and his book.
More than once, I've modified an anchor after my second has come up and I've been thinking things through while he's climbing. The fall dynamics may be completely different for the leader. Yeah, I should have worked it out before belaying the second but sometimes looking at the situation makes new possibilities apparent.
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dktem
Trad climber
Temecula
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Mar 10, 2010 - 10:29pm PT
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I have never been able to move rope as quickly and smoothly from a remote located belay device as I do when the belay device is right in front of me.
I agree with this one completely. I've tried belaying off the anchor and it almost always seems awkward and unsafe. Even tried the newfangled belay devices made for that purpose. If it's attached to your belay loop, it can't get away from you.
[...]Some of the force of the fall will be absorbed by the belayers bodie before forces are transmitted to the anchor. A good idea, just be sure the force through the body is very limited. Under the right circumstances, falls can generate thousands of pounds of force. You definitely don't want that kind of energy going through your spine. A good system should use the rope as the primary shock absorber.
I prefer to put as little loading as possible on gear. You never know how good an anchor is until you load it
I think the one of the goals in learning to build anchors is to know how to recognize how good an anchor is, or at least how to know that it's good enough. I don't claim to be the expert here, but I that's my goal in the learning process. In my view, a "good" anchor is one where we can be confident that the gear will do it's job.
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mongrel
Trad climber
Truckee, CA
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Mar 10, 2010 - 10:33pm PT
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Largo strikes again with a superb summary of the whole deal, and even brings the thread drift back to the OP: yes, tying into the anchor with the rope is recommended, basically.
And sometimes, just don't frickin' fall.
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Tomcat
Trad climber
Chatham N.H.
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Mar 11, 2010 - 08:43am PT
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Personally,I don't think anyone in the history of the sport has contributed as much to rope and anchor knowledge as Jim E..
One reason these discussions tend to go a bit awry is that we don't start out defining how we climb.Tradchick and I do 95% of our climbing on doubles.Doubles,or twins,in my opinion,put the final nail in the cordelette coffin,if you can't get a pretty well equalized,quick,efficient safe anchor together with two ropes and no cordelette,give up.I'd consider carrying a lette if I climbed multi pitch trad on a single,but that's about it.
It seems like a lot of the excitement about cordelettes comes from the guiding industry,which has an overwhelming emphasis on escaping the belay,and belaying directly off the anchors.I think rgold has stated what I will too,in thirty years of climbing,rock,ice,sport,trad,you name it,I've never had to escape a belay,but many times have had to settle for less than perfect anchors,where I was glad to use my body to absorb some of the load.
I'm not saying I will never have to do a belay escape,but will say the practiced scenarios won't always apply.Better to have a brain than a fixed procedure.
Your biggest risk,in my opinion,in a FF2 incident will revolve,quite literally,around the type of belay device you employ.If you don't know what I mean,find out.The Jesus nut is,as Largo states,the best thing going.At times where it's tough right off the belay,I'll belay lower than others,and use the anchor for Jesus.Other times I'll start up the next pitch,place a piece,and climb back down to the belay.
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tradmanclimbs
Ice climber
Pomfert VT
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Mar 11, 2010 - 08:44am PT
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Am i missing something all these years or is there some majick rope trick that allows you to lead in blocks and still use the rope as the anchor?
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