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marky
climber
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Topic Author's Original Post - Jul 11, 2007 - 04:07pm PT
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browsing through reviews of Long's revised Climbing Anchors monograph, one of the blurbs said, essentially, that the cordelette is now passe, made obsolete by the ... equalette
well, I'll buy the book soon enough. In the meantime, would someone offer a primer on this equalette business
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Largo
Sport climber
Venice, Ca
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Jul 11, 2007 - 04:19pm PT
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The Cordelette is still a viable rigging system under many situatioons, especially when the anchors are bomber, or when you are doing slow-pull type of stuff for hauling and rescue work. The cordelette is not your methodd of choice once the placements get less than ideal, mainly because the shortest arm in the cordelette will stretch the least and absorb a dissproportionate amount of the load -- like most of it. Testing showed that in very few cases does the cordelette approximate equalization, which opens up a greater question about equlaization as a hard and fast rule - when it is crucial and when it might not be so absolutely essential (though always desired).
JL
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andanother
climber
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Jul 11, 2007 - 04:55pm PT
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I know this topic has been beat to death, and both systems have their positives and negatives.
But if there was a peice of questionable gear in my anchor, I would definitely NOT use an equalette.
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the Fet
Knackered climber
A bivy sack in the secret campground
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Jul 11, 2007 - 05:07pm PT
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The equalette will allow you to equalize 2 pieces, with 1 or 2 more backup pieces that get weighted if a primary piece fails.
You could do the same thing with a slidingX with limiter knots and another sling(s) going to a backup piece(s).
Edit: the slidingX can bind though, unless you know how to tie it to avoid binding.
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travelin_light
Trad climber
california
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Jul 11, 2007 - 05:08pm PT
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nooooooooooooooooooooooooooooo!!!
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rgold
Trad climber
Poughkeepsie, NY
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Jul 11, 2007 - 05:25pm PT
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My take is that the equalette is clearly the best way to rig a two-point anchor. The only trouble is that the two points in a two-point anchor tend to be bolts, and if they aren't relics from the quarter-inch age, are really not in need of serious equalization. But if you are rigging a two-point gear anchor, the equalette is unquestionably the best method.
The situation for three point anchors, which probably make up the majority of gear anchors on trad climbs, is far less clear. The equalette with clove hitches is going to deliver about half the total load to one of the three pieces, which is, on average, what happens with a traditional cordelette. The possible discrepancies in the arm length mentioned by Largo, the impossibility of making the arms exactly the correct length, and the uncertainties about how much slack will be ejected from the powerpoint knot under loading all contribute to unequal loading.
The equalette with clove hitches enjoys the advantage of reorientability. Cordelettes will typically transfer the entire load to a single anchor if the load is off the axis the cordelette was tied for.
The self-equalizing schemes that have sprung up in response to the equalette's success are complex, unpredictable, gear-intensive, and may suffer so much from friction that they end up no better than a cordelette.
In spite of very poor behavior in off-axis loading, I don't think either the cordelette or direct rope tie-ins will die unless much better three-point anchor systems emerge. An intelligent approach to using the traditional methods is to deploy low-stretch slings strategically in the anchor in order to keep the cordelette or rope tie-in arms as close to the same length as possible.
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the Fet
Knackered climber
A bivy sack in the secret campground
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Jul 11, 2007 - 06:18pm PT
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"But if you are rigging a two-point gear anchor, the equalette is unquestionably the best method."
Except a slidingX pretied with limiter knots doesn't require you to tie two clove hitches at each anchor, and is therefore faster. So I like it better.
e.g.
"The equalette with clove hitches is going to deliver about half the total load to one of the three pieces, which is, on average, what happens with a traditional cordelette."
If I remeber correctly from the testing Largo had done (which I can't seem to find now) the cordelette only put about half the load on one piece when the arm lenghts were equal. Otherwise the majority of the load went to the piece with the shortest arm.
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andanother
climber
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Jul 11, 2007 - 07:06pm PT
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nice.
I'm sure the box plot diagram will show up somewhere within the next 50 posts.
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Chiloe
Trad climber
Lee, NH
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Jul 11, 2007 - 07:21pm PT
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I'm sure the box plot diagram will show up somewhere within the next 50 posts.
No it would make you sneeze.
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wootles
climber
Gamma Quadrant
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Jul 11, 2007 - 08:11pm PT
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If I remeber correctly from the testing Largo had done (which I can't seem to find now)...
Which I will likely never forget no matter how much I try.
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Largo
Sport climber
Venice, Ca
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Jul 11, 2007 - 09:43pm PT
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Wottles did the testing, not I. It is all his fault. His was the start of a very interesting and also fatally boring subject.
JL
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rgold
Trad climber
Poughkeepsie, NY
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Jul 11, 2007 - 09:55pm PT
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"Except a sliding X pretied with limiter knots doesn't require you to tie two clove hitches at each anchor, and is therefore faster."
You are referring, presumably, to the diagram attributed to Healyje and most recently posted by...yourself. That diagram has one clove hitch at each anchor, not two. There are, however, four anchors. If you don't put those clove hitches in, you've got a double american death triangle which, in some situations, will only load the higher of each anchor pair. (Think for example, of the very natural situation of two anchor pairs, each pair in a vertical crack.)
Although I was thinking of far more complex set-ups, this illustrates my point about so many of the new systems being complex and unpredictable. (1) The current one, whatever its speed of deployment, just doesn't work for some very natural four-anchor configurations if you aren't going to use the clove hitches, in which case it has no speed advantage. (2) In addition, note that the pretied sling, as depicted, won't work for two anchors in a horizontal crack without adjusting the stopper knots, which may be hard to move if the sling has been loaded.
The picture posted is a minor variation of the Largo equalette. There are some other variations too. My comment about it appearing to be the best way to rig a two-point anchor applies to the variations too; they shouldn't be offered as contrary evidence.
"If I remember correctly from the testing Largo had done (which I can't seem to find now) the cordelette only put about half the load on one piece when the arm lenghts were equal. Otherwise the majority of the load went to the piece with the shortest arm."
I think you missed the point. Largo, Wootles, and Chiloe tested cordelettes with two-point anchors, at least as far as I know. My reference to one of the three anchor pieces getting half the load on average is from tests done by Attaway for three-point anchors rigged with cordelettes. I won't say any more about that to spare those who, in some inexplicable fit of masochism, are reading this while wishing they weren't.
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LuckyPink
climber
the last bivy
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Jul 11, 2007 - 10:22pm PT
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just looked thru the book a week ago and tried out the equilette! LOVED it. Fast to place / clean and works great I thought. sold on it. highly suggest anyone interested actually read the book, pics too.
Met some folks in the parking lot< leader had taken a 65 ft fall on Charlotte, force popped cordellete off the big slung chock stone, flipping the chockstone up into the face of the belayer, other piece in anchor held.. totally unequalized upon the fall. there were injuries but coulda been worse. equilette might have shared the load better.
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wootles
climber
Gamma Quadrant
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Jul 11, 2007 - 10:51pm PT
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Wottles did the testing, not I. It is all his fault. His was the start of a very interesting and also fatally boring subject.
JL
I really did enjoy working on all this and the ensuing discussions. A lot of really cool stuff came from it.
I do wish, however, that people would read the book and the various other threads on the topic before offering up "new" opinions and ideas. New threads on the subject are grounds for a lynching.
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Thom
Trad climber
South Orange County, CA
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Jul 11, 2007 - 11:23pm PT
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LuckyPink,
You may have missed the point of your own post:
The cordelette held.
JL has mentioned how these discussions have opened the door for additional, and perhaps more pertinent, questions:
In our somewhat vain attempts at equalization we don't see bolts, cams, stoppers, cordelettes, or slings blowing apart even under some serious falls, so perhaps we're overthinking this thing and making more out of it than we should.
(I've witnessed some pretty serious and heated discussions over the use of oval 'biners and "D" 'biners: ovals are weaker, blah, blah, blah... they'll both hold a small car, get over it.)
Cordelette, Equalette. As long as you make some attempt at equalization while understanding the forces you're potentially dealing with, I don't think it matters much; you're not likely to die; use what you're comfortable with. JMO.
T.
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nick d
Trad climber
nm
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Jul 11, 2007 - 11:37pm PT
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"Fatally boring" Now that's funny!
I rely exclusively on 6 rurps clove hitched together.
MS
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WBraun
climber
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Jul 11, 2007 - 11:45pm PT
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In 71 I jugged to anchor that Charlie Porter made and there it was 3 fuking rurps equalized in a vertical row.
Right then and there I saw the possibilities for future anchors and what was possible.
Big fat ass bolts are OK and make life very easy on big aid routes. They even speed things up immeasurably. (One big reason for one day speed ascents of big aid routes.)
But there's just nothing like fukin around making trippy anchors with gear, which is becoming more and more a lost art.
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LuckyPink
climber
the last bivy
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Jul 12, 2007 - 12:03am PT
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Thom, hard to say having not been there myself, but it sounded like the anchor held via the one piece, but that the cordellette did not equalize therefore blowing out the slung stone (center) which was large, about the size of your average cooler. Human error in building anchor? Unequalized cordelette? dunno, but it seems better equalization may have kept it in place. Have you tried the equalette yourself?
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Tom
Big Wall climber
San Luis Obispo CA
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Jul 12, 2007 - 12:17am PT
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WVB:
First of all, it was more like five rurps, clove-hitched together.
Second, it was Bridwell, not Porter.
Third, it was Dale Bard, not you.
Get your story straight, or get in line behind the rest of us 8-)
That cloved-up equallette looks like it could come in handy, even for a wall/hauling anchor. Trying to tie a fig-8 in the three tails of a cordelette to get equal tension in them can be a PITA.
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