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Karl Baba
Trad climber
Yosemite, Ca
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Jun 30, 2008 - 02:45pm PT
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Macolm's rule's are total BS, except for #2 which is on the money.
But the OP talked about using the x for PROTECTION.
Much better to use a screamer on necessary but dicey pro in my mind.
Peace
karl
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Prod
Social climber
Charlevoix, MI
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Jun 30, 2008 - 03:04pm PT
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Use it, as well as a tied off cordalette, and have used the equelette, and have tied in with rope to gear, and one of my favorites is to wedge my feet against a tree on a hip belay (bringing up lighter climbers on easy stuff).
Basically I agree with TP.
MAL,
Your system seems complicated. I try to keep it to your rule #1 as a rule, and your rule #4 as a principal applied where necessary.
On a completely other note, at the same time I am writing this I am writing a note to my girlfriend. I nearly signed this Love Guy.
Love,
Prod.
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Moof
Big Wall climber
A cube at my soul sucking job in Oregon
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Jun 30, 2008 - 03:06pm PT
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Yes I use it, but yes it has limitations. Usually I end up using it in part of a larger setup, when I have 4 good pieces for downward (cuz sometimes I just can't help myself when placements are begging for gear!). I'll sliding X together a couple pieces to creat 3 points for the cordalette, and try to get another piece for upward pull. Usually the rock dictates the anchor more than rc.com, or Largo's most recent rant.
I objected to the sliding X being used by my partner only once, none have objected to my use of it so far (not to my face anyway). The anchor was 2 bolts, which he equalized with a 2' runner on a sliding X using lockers all around. My only gripe was that there was no redundancy if the sling failed. I know the sling isn't going to fail, but I really want redundancy against any single point failure. From then on he used 2 slings together, problem solved. In the same situration I usually using either two slings, one per bolt, or a 4' sling with a figure 8 knot at the bottom. With bomber bolts, redundancy is more important than equalization.
Strictly speaking SRENE is an oxymoron. You can't Equalize AND have No Extension for a multi-directional anchor. The best you can do is SRELE (surreal), where you aim for "Little Extension".
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bluering
Trad climber
Santa Clara, Ca.
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Jun 30, 2008 - 03:09pm PT
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Yep, I use it fairly often at anchors. Sometimes a cordalette, sometimes a SX, sometimes a funky combo of a SX and another piece slung to the x.
It's all situational. Just refer to Mal's rule#2 and quite overanalizing. Well, you're buddy was the one complaing, not you, so tell him to STFU and read largo's book.
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piquaclimber
Trad climber
Durango
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Topic Author's Reply - Jun 30, 2008 - 03:59pm PT
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Karl is right, I was asking about using the x for protection on a pitch, not for anchor purposes. Sorry for my poor communication.
I agree about the screamer Karl... if it's that sketch and if I have the gear available, I use the X with a screamer at the clip in point.
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Largo
Sport climber
Venice, Ca
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Jun 30, 2008 - 04:05pm PT
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One of the things that gets overlooked in all these discussions is something we confirmed during testing - namely, that all systems with a sliding powerpoint are prone to binding (as in the sling binding when weighted, negating the sliding motion) in what is known as the clutch effect. Using an anodized, pear-shaped biner all but eliminates the binding, so go with that.
JL
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piquaclimber
Trad climber
Durango
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Topic Author's Reply - Jun 30, 2008 - 04:11pm PT
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John,
Do you think the clutch effect can be partially mitigated by placing the bartracks of a swen sling in a specific place in the setup? Is the bartrack involved at all in the binding that you saw?
Or do you think the clutch effect is multiplied or reduced depending on the type of sling you are using? (Nylon vs Spectra)
Cheers,
Brad
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Largo
Sport climber
Venice, Ca
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Jun 30, 2008 - 05:05pm PT
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John,
Do you think the clutch effect can be partially mitigated by placing the bartracks of a swen sling in a specific place in the setup? Is the bartrack involved at all in the binding that you saw?
Or do you think the clutch effect is multiplied or reduced depending on the type of sling you are using? (Nylon vs Spectra)
Cheers,
Brad
BRAD:
I THINK IT IS SIMPLY A CASE OF FRICTION COEFFICIENT, MEANING THAT WHATEVER SLING MATERIAL YOU USE, IT TENDS TO BIND ON REGULAR ALUM., WHILE IT SLIPS ON THE POLISHED ARTICLE. SLING MATERIALS VARRY IN SMOOTHNESS (AND PRODUCE LESS FRICTION/BINDING) AND THIS MIGHT BE WORTH LOOKING INTO.
JL
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maldaly
Trad climber
Boulder, CO
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Jun 30, 2008 - 05:10pm PT
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rgold, you're forgiven for the geek nature of your posting. As usual your comments are accurate and insightful. Thanks for chipping in but don't ever do that again.
To all the other posters, I agree: Rule #2 is the best.
Mal
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Matt
Trad climber
primordial soup
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Jun 30, 2008 - 05:23pm PT
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lately though, i've been attaching the lead rope directly to the anchor pieces with clove hitches. this doesn't equalize 100% but no shock load occurs if a piece fails.
how many people do this?
i think this type of anchor was the culprit when those CO guys ripped off the DNB a few years back.
i know there is a fondness for the craft involved, one which goes to the famous photo of that bridwell anchor, but i have always felt like that type of anchor was basically cutting corners, and best to be used only when nothing else would work.
honestly, i don't understand the argument in favor (i.e. "this doesn't equalize 100% but no shock load occurs if a piece fails").
if you haven't really equalized anything (and you haven't), then you basically are loking at sequential shock-loading of as many pieces as it takes before one holds individually, or they all pop.
am i missing something?
(and yes, i am familiar with the ins and outs of a clove hitch)
EDIT
i agree entirely w/ the post below, by TP
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tolman_paul
Trad climber
Anchorage, AK
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Jun 30, 2008 - 05:33pm PT
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I've used the clove hitches in situations where, I was setting up a quick anchor, each point was bomber, and I was situated to where I was belaying from my harness and a fall wouldn't have loaded the anchor.
There are many different situations one finds themself in and anchors are built and equalized accordingly. I've used anchors that I wouldn't even trust to rappel on, and others I could use to winch a truck up, and most fall somewhere in between.
I guess my typical anchor would be a long loop of 1/2" supertape, equalized between 3 anchors, and tied with an overhand at the master point. The three point sliding X really suffers from friction, and when the webbing is long enough to allow the overhand knot it cleans it up a bit.
But it all depends. Best is knowing many different anchors, pros and cons, and using them as needed on a case by case, belay by belay situation.
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maldaly
Trad climber
Boulder, CO
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Jun 30, 2008 - 05:39pm PT
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tolman_paul,
The last sentence in your post is now my rule #5.
Mal
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bluering
Trad climber
Santa Clara, Ca.
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Jun 30, 2008 - 05:47pm PT
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Since piqua was talking about using the sx to equalize two pieces of LEAD PROTECTION for redundancy, clove hitching the two pieces would work also instead of a sx. I've done it, seems to work fine. Of course you gotta get the hitches just right for it to work effectively.
Of course, the hitches are probably better when setting two OPPOSING pieces.
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rgold
Trad climber
Poughkeepsie, NY
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Jun 30, 2008 - 09:38pm PT
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Mal (and Paul), I've enrolled in Over Anal - yzers Anonymous and have been through their 12-step program and...still...can't...help...geekish...posting...eeeaaaahhhhHHHH!
In my opinion, Jim's testing does show that extension in a sliding system used to equalize pro is of little concern, because in the case of pro the extension will almost always be tiny compared to the amount of rope absorbing energy. So the pro situation is very different from the anchoring situation, and this makes the sliding X or, better, an equalette, a good choice for two questionable pieces. The equalette will, in many cases, be too tricky to tie while leading, while the sliding X, although more subject to binding, is easily installed with one hand.
An issue I've never seen discussed with the sliding X is what happens to the power-point biner if one of the anchors fails. A turn of webbing holding the failed anchor is going to tighten around the power point biner, with significant potential for opening the gate or cross-loading the biner. Because of this, I'd say that the power point in a sliding X set-up on pro should always consist of two biners with the gates opposed.
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Jaybro
Social climber
wuz real!
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Jun 30, 2008 - 09:45pm PT
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of course not... trick question?
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Lost Arrow
Trad climber
The North Ridge of the San Fernando
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Jun 30, 2008 - 10:10pm PT
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I no longer use a sliding x. I tie in to a bomber with the rope and than back that piece up with more pieces and webbing to a single locker.
JDF
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Ed Hartouni
Trad climber
Livermore, CA
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Jun 30, 2008 - 10:13pm PT
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Answer the question:
I use the sliding-x sometimes, usually in a 3 piece anchor where it equalizes two pieces and the the rope goes to the third piece by a clove-hitch.
Sometimes I use the cordelette in the same manner, depends on the distance of the pieces.
Sometimes I use the cordelette with three pieces, especially if the legs are pretty much equal in length.
I always try to to follow Mal's first three rules...
The accident on the DNB will never be definitively analyzed. However it is possible that a flake blew and that all the pieces were behind the same flake. Note that that arrangement violates Mal's rules 1 through 3, and those people were experienced.
Read the accident report...
http://www.supertopo.com/climbing/thread.html?topic_id=554557&msg=557937#msg557937
I did try to measure the coefficient of friction in the "sliding x" configuration, the "clutching" can be significant, but it depends on how the sling sits, on top of each other or next to each other... so not a reliable setup, but less of a force differential than the cordelette in a very "asymmetric" configuration (one leg much longer than another).
As for "shock loading" analysis would say that it has to be a factor... so it would be interesting to push the analysis difference of the tests and the calculations... there is some good wisdom hiding in there that a concerted effort at understanding would reveal.
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k-man
Gym climber
SCruz
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Jun 30, 2008 - 11:26pm PT
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... OT from the OP ...
Using the lead rope to anchor, a friend showed me how to "equalize" with a bowline-on-a-bite.
FOLLOW RULE #3!
I now use this at all two-bolt belays.
A single biner on each bolt. Fast, and the least amount of gear
you can possibly use. You can adjust the bowline, if needed, to
assimilate a degree of "equalization."
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tom woods
Gym climber
Bishop, CA
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The thing with anchors is that we build them fro two purposes. For the follower and for the leader. For the folllower, barring an extreme swing, you could body belay the person from a good ledge.
For the leader, (that's what got the DNB folks a couple of years back) you're building a an upward or mulit directional anchor, but you have body weight on your side.
Things get interesting until you get back to the old schoolers and the leader must not fall mentality. I don't like falling either so problem solved, QED.
Tom
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Gobie
Trad climber
Northern, Ca.
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Did anyone read the OP??
Karl is obviously the only one that did.
It doesnt say anything about belays. Do rules 1-4 apply to protection as well? I wish all my pro was bomber, sometimes I settle for what I get. Hopefully it will slow me down before I get to rules 1-3 and its strong enough to apply force to rule 4.
Answer to question. I would prefer to extend my (dubious) pro to be as close to equal to each other as possible even if this results in a little bit longer of a fall. I did this once with a small brass hb and a loweball. I thought it was cute at the time and then I got higher and realized that it was my pro. I fell and pulled the hb and the loweball held. I cant be convinced this would of happened if they were on an X. I didnt have a calculator, or time to think about it, my brain just works that way.
"Have you ever been experienced...well I have."
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