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clmbnski
Mar 4, 2006, 2:41 AM
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Inspired by the discussion in the sliding x thread Edit: You may want to read through the thread a bit before posting if you have never heard of the issues involved. ... I guess I screwed up the poll when I edited the topic
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rockguide
Mar 4, 2006, 2:56 AM
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The cordellette system is excellent ... I usually use 19mm sling instead of 7mm cord now for strength over an edge, but still use 6 or 7mm cord on occasion. I also use the sliding X (with two limiting knots) and many other ways of building anchors - including, occasionally tying the pieces together with rope. Toolbox, meet terrain. Terrain, this is my toolbox. If anybody is looking for the one system that will work all the time in all situations, they would be better off looking for the Holygrail. I would join the quest, but I lost the coconuts and I cannot face the killer rabbit again. Brian
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moose_droppings
Mar 4, 2006, 2:59 AM
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Of course I'll continue to use it, different tools for different situations. There will always be a search for the holy grail, (i don't think there is one myself) and the next one will have a few hairline cracks in it too.
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sactownclimber
Mar 4, 2006, 3:18 AM
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I'm intrigued by the discussion in the "sliding x" forum . . . I've read about half of it so far. The cordelette is a useful tool, in spite of it's imperfections.
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gordo
Mar 4, 2006, 3:18 AM
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It continues to have it's place in anchors with bomber pieces and no reall need for equalization. I won't use it in a situation where the placements are not ideal. There are better solutions.
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tattooed_climber
Mar 4, 2006, 5:46 AM
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cord is the most adaptable tool when used: right, safetly, smartly, etc. :roll: trad ain't no amateur arena...last thing i want to see near me is an explosion at the spaghetti factory
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dingus
Mar 4, 2006, 5:56 AM
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I use the Holy Grail for all anchors. Thank uyou. Thankyouverymuch. DMT
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bloodyhands
Mar 4, 2006, 8:51 AM
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The cordelette, may not be the best of equalizing systems, but it is by far the simplest. I doubt it will ever go out of style.
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keithlester
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Mar 4, 2006, 1:56 PM
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I have never used a cordelette, on short pitches I connect to my anchors with the climbing ropes, using half ropes this often suffices. Otherwise I supplement this with long slings, 8ft long, I usually carry 2 or 3 of these and rarely need more than one to connect up.
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ridgeclimber
Mar 4, 2006, 2:56 PM
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I use almost exclusively cordellete anchors. I have never had any problems with equalization at all. It's simple and there are so many ways to use it; a second clipping point at the top shelf, for one.
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roy_hinkley_jr
Mar 4, 2006, 4:18 PM
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Cord-a-death works great...till it doesn't...it's a long riiiiiiiide dooooown.
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reno
Mar 4, 2006, 4:45 PM
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Vesatile. Doesn't do everything perfectly, but does several things "pretty well." It will continue to have a place on my rack, and, like everything else on the rack, used when appropriate and not used when not appropriate.
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pbcowboy77
Mar 4, 2006, 6:17 PM
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If you know how to use it and little tricks with it, it's great. It's simple not much thought goes into it. You can use it for other things than the anchor i.e. sling something to bail, cut it for pursiks, first aid, blah blah blah. So why not carry one? Are you trying to savr weight? Are you gonna use the rope for the anchor and make it a bit shorter for the next pitch? Are you gonna use up sling and run out on the next pitch? There are hundreds of diffrent ways to build an anchor, why not have every option at your side.
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jabtocrag
Mar 4, 2006, 7:59 PM
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In reply to: ... I usually use 19mm sling instead of 7mm cord now for strength over an edge... Seems like overkill :wink:
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rockguide
Mar 5, 2006, 6:00 AM
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In reply to: In reply to: ... I usually use 19mm sling instead of 7mm cord now for strength over an edge... Seems like overkill :wink: I just get no slack. where is the love for paranoia? :lol: :lol: :lol: On some terrain I find myself slinging blocks rather than tying pieces together. 19mm sling is substantially better than round cord on the rough limestone here - and almost as easy to work with. Top rope anchors that hang over edges and see abrasion over the day are also a good application for the flat tape rather than the round tape. Multi pitch anchors ... hanging clean ... round cord is fine and easier to work with (and, in theory, the cord also helps in improvised rescue. Sorry - some guy explained to me that rock rescue is a myth in another thread ... so forget that :lol: ) Brian
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gonzo
Mar 5, 2006, 9:10 AM
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I use the wild country ready made cordelette. It is made of dyneema sling, I think around 22kN, so it's very thin, easy to rack up and handle and much stronger then standard perleon. Only disadvantage is that its pretty pricey.
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rad_dog
Mar 5, 2006, 3:01 PM
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I don't use cordolettes, but then again I'm not a fan of trad draws either. I usually just equalize anchors using the stuff I normally carry - regular shoulder length slings, quick draws, and the rope. If I'm going to be top roping I carry a 25 foot scrap of static caving rope that somebody gave me. It's so much nicer than messing up your good slings or trusting webbing over edges. But hey, if you like that cordolette and it's working for you - go for it.
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devkrev
Mar 5, 2006, 3:35 PM
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One of the major advantages that I see with a cordelette is that it keeps the rope free from the anchor. If you have a problem that requires you to rescue a stuck partner for whatever reason, it will be ALOT easy to do if the rope isn't all tied up as an integral piece of the anchor. Thats just my opinion, though, but I'm just a noob, what do I know dev
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dingus
Mar 5, 2006, 4:03 PM
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In reply to: One of the major advantages that I see with a cordelette is that it keeps the rope free from the anchor. If you have a problem that requires you to rescue a stuck partner for whatever reason, it will be ALOT easy to do if the rope isn't all tied up as an integral piece of the anchor. Thats just my opinion, though, but I'm just a noob, what do I know dev What you don't know is the dreaded shock load of an anchor (or the belayer's pelvis) rises considerably when you don't incorporate a dynamic component into your anchor. DMT
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altelis
Mar 5, 2006, 4:17 PM
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....and what you don't know might kill you......
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tradrenn
Mar 5, 2006, 4:43 PM
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In reply to: Cord-a-death works great...till it doesn't...it's a long riiiiiiiide dooooown. Care to elaborate your point ?
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scrapedape
Mar 5, 2006, 4:56 PM
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In reply to: In reply to: One of the major advantages that I see with a cordelette is that it keeps the rope free from the anchor. If you have a problem that requires you to rescue a stuck partner for whatever reason, it will be ALOT easy to do if the rope isn't all tied up as an integral piece of the anchor. Thats just my opinion, though, but I'm just a noob, what do I know dev What you don't know is the dreaded shock load of an anchor (or the belayer's pelvis) rises considerably when you don't incorporate a dynamic component into your anchor. DMT Doesn't the advantage lie in establishing an anchor with a powerpoint, whether you use a cordelette or some other method? You can clip into that powerpoint with your rope, so you have a dynamic link between you and the anchor, but can still escape the system more easily than if the climbing rope is goingto each piece in the system.
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roy_hinkley_jr
Mar 5, 2006, 5:02 PM
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In reply to: In reply to: Cord-a-death works great...till it doesn't...it's a long riiiiiiiide dooooown. Care to elaborate your point ? Sure. I'll quote John Long from the other thread:
In reply to: A dozen years ago, I promoted the cordelette across the board. Testing found that it didn't work as advertised--or even close to as advertised. Unless a cordelette has perfectly equal length arms, and is attached to TWO side by side placements (like bolts), it does not function remotely as well as other systems. You should not use the cordelette to connect 3 pieces in ANY configuration. In fact, if you are trying to rig up anything but two side by side pieces, there is no such thing as a "well made cordelette." They were never safe to begin with but, based on the poll results so far, the lemmings keep on trusting in divine intervention.
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clmbnski
Mar 5, 2006, 5:49 PM
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I will elaborate some more for those not familiar. Testing conducted recently by John Long et al. has found that the cordelette fails to equalize the forces when it is loaded. This was somewhat known but I guess never really investigated thoroughly. The problem is due to (let me know if I am missing something) the different length arms in the cordelette stretching at different lengths and therefore loading the shortest arm piece the most. Also, the fixed power point does not adjust for loading from an unexpected direction. I would like to see the data for how bad the equilization really is and the way the drop tests were conducted. Hopefully that goes into the new book or a paper is written up on the testing. So there has been attempts at creating new anchor systems: see sliding x thread. Personally, I will keep using the cordelette unless something is invented that is similarly quick, versitile, and relatively simple unless I am faced with a situation where the pieces in the anchor are weak and equalization is manditory for strength. Chris
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akicebum
Mar 5, 2006, 6:10 PM
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For all haters, here are a few questions: 1: With a Weballete, Trango instant anchor, or Metolius PAS can you make an effective prussik? 2: Can you make a V-thread out of any other anchor system? 3: With the exception of the weballete, can you make knotted chocks out of any other anchor system? I just got back from a trip with the ultimate "gear guy." He was ranting and raving about his PAS. I think they work great myself, but in the mountains or on longer routes, I am more comfortable with my cord because it is more versatile when things don't go as planned.
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roy_hinkley_jr
Mar 5, 2006, 6:19 PM
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In reply to: For all haters, here are a few questions: 1: With a Weballete, Trango instant anchor, or Metolius PAS can you make an effective prussik? Yes, though a Hedden hitch is better most of the time.
In reply to: 2: Can you make a V-thread out of any other anchor system? Yes, though never needed to on rock. Even with a cordadeath, you can't make one on ice without carrying a special tool.
In reply to: 3: With the exception of the weballete, can you make knotted chocks out of any other anchor system? Yes, quite easily.
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clmbnski
Mar 5, 2006, 6:20 PM
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(In regards to the poll) Ignore the duplicate options until someone fixes it, Im going to quit screwing with it. :roll:
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stymingersfink
Mar 5, 2006, 10:26 PM
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where else am i going to find something on my rack that I feel good about: cutting lengths to replace that ratty ol tat hanging from some rarely-used rap anchor cutting to length for v-threads slinging HUGE 'cicles with, that double-length slings would never fit around slinging huge boulders/rock horns/flakes that standard slings won't fit over extending an anchor to better facilitate bringing up a second Personally, even with the discussion surrounding the whole "improved-x" brou-haha I'll continue using my 8mm dynamic to build anchors with, in as intelligent a manner as possible for each given situation. Sliding-x+limiting knots+large basket biner while paying attention to arm length and angles, same as always. Hey, it's not perfect, but its as close as can be given the tools to work with in the situation i'm in.
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akicebum
Mar 5, 2006, 10:42 PM
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WHAT!!! "you cannot make a v-thread without a tool." Thats bullshit, I've done it more times than can count. A haden hitch works, but sometimes if binds, but it is true, though only with a weballette or sling. whatever I'm stickin to my cord. besides cord costs nothing compared to the presewn systems.
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trebork2
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Mar 6, 2006, 10:25 PM
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I think 8mm cord is the way to go. If you know how to build anchor systems correctly then I believe it works fine. I believe the problem with it lies in the climbers out there that don't know how to build a correct anchor system. I bet you that 75% of the climbers out there don't know how to build correct anchor systems. The same probably goes with know how to place a proper piece of protection. If you can't place the protection right anything is going to fail on you. I play it as safe as possible. I use a minimum of three anchor points, make sure everything is equalized and multi-directional. Maybe a lot of people need to go back to the basics of SRENE
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tradrenn
Mar 6, 2006, 11:29 PM
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In reply to: In reply to: In reply to: Cord-a-death works great...till it doesn't...it's a long riiiiiiiide dooooown. Care to elaborate your point ? Sure. They were never safe to begin with but, based on the poll results so far, the lemmings keep on trusting in divine intervention. I guess I'm owned on this one I didn't read the other thread till late night yesterday. I do like Gordolette thou. Let me see what happends, I'm only on page 12 so far.
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tradklime
Mar 6, 2006, 11:57 PM
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It's funny that many people are arguing for a cordalette anchor by the virtues of having cord when climbing. There are many alternatives to the traditional cordalette anchor using the exact same cord. Perhaps its a simple terminology misunderstanding. Anyway, for those that cling to their cordalette anchors... til death do you part, eh? :lol:
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ryko
Mar 6, 2006, 11:58 PM
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In reply to: I will elaborate some more for those not familiar. Testing conducted recently by John Long et al. has found that the cordelette fails to equalize the forces when it is loaded. This was somewhat known but I guess never really investigated thoroughly. The problem is due to (let me know if I am missing something) the different length arms in the cordelette stretching at different lengths and therefore loading the shortest arm piece the most. Also, the fixed power point does not adjust for loading from an unexpected direction. I would like to see the data for how bad the equilization really is and the way the drop tests were conducted. Hopefully that goes into the new book or a paper is written up on the testing. So there has been attempts at creating new anchor systems: see sliding x thread. Personally, I will keep using the cordelette unless something is invented that is similarly quick, versitile, and relatively simple unless I am faced with a situation where the pieces in the anchor are weak and equalization is manditory for strength. Chris If there is any inkling to these things not working as advertised, I'm surprised they're still on the market. If a fatal fall is investigated and determined that it was due to anchor failure at the cordelette, that's one major lawsuit. I've used cordelletes quite extensively. Makes me wonder about using it now for anything other than top-rope or slinging a large block. :cry:
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moose_droppings
Mar 7, 2006, 12:08 AM
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In reply to: I use a minimum of three anchor points, make sure everything is equalized and multi-directional. Maybe a lot of people need to go back to the basics of SRENE Would you care to show me this anchor that can do this and still remain; Simple Redundent Equalized No Extension
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healyje
Mar 7, 2006, 12:31 AM
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John, From these discussions I'd say one take away is to be really carefully what you write this time around as anything you say ends up like a screw stuck in a tire going round and round. It's quite amazing how powerful the con-joined influences of learned skills and practiced habit can be such that one won't relinquish something even when confronted with the fact that is is often deficient.
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sweetchuck
Mar 7, 2006, 12:40 AM
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So many people have been using the cordelette for so long. So now it's deficient and dangerous. It seems like there should be at least a few scary cordelette stories out there. Has anyone had a leg of their cordelette blow (how and what happened next)? Anyone hear about a cascade failure? I am just curious. I too have been following the sliding x thread, and am rethinking my cordelette. I guess I'm not expecting a holy grail, but I do hope a simple stable solution might come out of it. So, any cordelette horror stories???!!!
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jakedatc
Mar 7, 2006, 12:40 AM
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In reply to: If there is any inkling to these things not working as advertised, I'm surprised they're still on the market. If a fatal fall is investigated and determined that it was due to anchor failure at the cordelette, that's one major lawsuit. It's not the cord that is failing.. it is the system created that has not faired well in the drop tests. all those prepackaged "cordalettes" are just 7mm cord tied together for marketability. what you do with it after is not the cord maker's problem. 7mm cord is used for alot of things.. they arent going to take it off the market
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patto
Mar 7, 2006, 12:46 AM
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In reply to: [Cordelettes] were never safe to begin with but, based on the poll results so far, the lemmings keep on trusting in divine intervention. How exactly aren't they safe? Sure they don't perfectly equalise across all pieces but that doesn't make things unsafe. You still have 3 pieces linked that should hold more than 10kN each, with the load spread over at least two pieces. Where the expected load is likely to be FAR less than 10kN. As far as I'm concerned I'm sticking with the cordelette and yes I have undstand and believe discussion in the sliding-x thread.
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healyje
Mar 7, 2006, 12:59 AM
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If I'm interpreting the test results right then cordelettes on more than two piece anchors simply fail at loads surprisingly below other designs.
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delcross
Mar 7, 2006, 1:09 AM
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philbox
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Mar 7, 2006, 1:35 AM
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The full test results have not been published yet. John does however describe the findings and that is contained within the sliding x thread. I implore everyone to read that thread before posting anything in this thread. Lotsa awesome discussion in that thread and in fact I will go so far as to say that the sliding x thread may be one of the most important discussions as far as climbers go that has appeared in years. I shall be linking to that thread from other climbing sites around the net. My thinking is that there is still a ways to go before this discussion has drawn any concrete solutions. Of course being the very inventive and resourceful souls that we are the discussion may never be finalised to a simple and effective anchor outcome that can be taught with confidence.
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vivalargo
Mar 7, 2006, 1:48 AM
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Hi, all: I only just received the initial data crunching and work ups from the statisticians, both nationally recognized PhD data wizards and experienced climbers. The drop tests themselves were conducted by the guy widely considerd the leading drop tester in the US, who has all the fancy UIAA drop towers and computer assist gear at his disposal. It took the poor guy weeks and hundreds of drop tests to finish the study. I can't post the actual graphs and box charts, nor yet the long lists of numbers. But I can quote an abridged version of a few paragraphs from the study that give a clear indication of how the cordelette performed under dynamic loading (factor one fall). These paragraphs concern the initial testing, done with the cordelette (in both equal and unequal arm length configurations) connecting only two primary anchor points. ------------- A. Cordelette, equal length: Tests simulating a factor 1 fall demonstrate that on average, a cordelette, equal length configuration generated an absolute difference in load that was a little less than 1 kN. Repeated measurements of the difference in the forces generated varied somewhat across multiple tests. Contrary to conventional wisdom and popular usage, the cordelette, with equal length arms is not a very effective system to achieve equalization. D. Cordelette, unequal length: This clearly-the-worst-configuration tested produces an absolute average difference in force between the anchor arms of almost 3.5 kN. Aside from generating the largest difference in force of the riggings measured, the cordelette, unequal length rigging was the most inconsistent when repeated measures of this difference was taken. In some cases, the difference in load measured was greater than 5 kN! To put it bluntly, the cordelette, unequal length configuration is the poorest performing anchor considered in all the testing conducted. Not only is equalization very poor, the degree of equalization varies wildly from fall to fall. This configuration is very unpredictable, except in that the difference in the forces generated from a fall will be high. The cordelette unequal length is simply to be avoided. Summary: While the equal armed cordelette distributes a dynamic load to an (barely) acceptable degree, and will no doubt remain a viable option in that configuration, a cordelette rigged with unequal arms is an inferior–and likely hazardous--choice when contrasted with the far more efficient load distribution of the sliding x and the equalette.
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healyje
Mar 7, 2006, 1:57 AM
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Worth repeating for those that want the abridged version:
In reply to: ...To put it bluntly, the cordelette, unequal length configuration is the poorest performing anchor considered in all the testing conducted...
In reply to: Summary: While the equal armed cordelette distributes a dynamic load to an ( barely) acceptable degree, and will no doubt remain a viable option in that configuration, a cordelette rigged with unequal arms is an inferior–and likely hazardous--choice when contrasted with the far more efficient load distribution of the sliding x and the equalette.
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roy_hinkley_jr
Mar 7, 2006, 2:16 AM
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In reply to: So, any cordelette horror stories???!!! Like this one at Tahquitz?
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sweetchuck
Mar 7, 2006, 2:36 PM
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Yeah Roy, just like that. I had forgotten that thread. Thanks. sc
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clmbnski
Mar 13, 2006, 10:37 PM
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...the poll is fixed
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mrpants
Apr 6, 2006, 7:35 PM
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For the record, I can't believe that given the now available information on cordelettes that nearly 70% of the poll respondents don't seem to think there is a problem with using them. John Long himself, the man who's anchor books are nearly universally read by any new trad leader, has pointed out some rather unsettling facts regarding the method. Are people simply unaware, or are they discounting his words because cordelettes just "seem" to make perfect sense?
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schveety
Apr 6, 2006, 8:35 PM
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Kind of an aside to the whole cordelette issue, but to Roy-Hinkley-Jr on the Tahquitz accident. I was up there this past August and talked to one of the climbing members of the rescue team who responded to that accident and he said that the two climbers were inexperienced with placing gear and were actually seen placing their cams like chocks and not in the camming mode. So who knows if that accident really was forces on the anchor or inexperience..............
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tomtom
Apr 6, 2006, 10:34 PM
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In reply to: For the record, I can't believe that given the now available information on cordelettes that nearly 70% of the poll respondents don't seem to think there is a problem with using them. John Long himself, the man who's anchor books are nearly universally read by any new trad leader, has pointed out some rather unsettling facts regarding the method. Are people simply unaware, or are they discounting his words because cordelettes just "seem" to make perfect sense? Well duh. I'm amazed that it took you this long to figure out that the cordelette isn't perfect.
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brutusofwyde
Apr 6, 2006, 11:28 PM
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I'm one of the folks who didn't respond to the poll. My choice, "It Depends" (TM) wasn't an option. Do I use a cordelette? Sometimes. On Walls, they are indispensible for keeping the rope from being trapped in the belay, especially when climbing in any number of styles requiring this: Leading in blocks, climbing as a team of three with limited cordage, etc. Do I use cordelette exclusively? Absolutely not. My belay setups range from using the rope exclusively ("pseudo-equalized," Atomic Clip, eights etc) to "Magic X" to a couple of slings clipped into bolts to rope tied around a single 4' diameter Ponderosa Pine like the one near the top of Steck Salathe'. To just myself, wedged in a crack or bracing against boots or skis with tails submerged. While it is indeed enlightening to study various setups to look at how individual pieces are loaded, we must remember that EVERY ANCHOR SYSTEM IS DIFFERENT. In fact, using the same pieces in the same geometric anchor configuration, with a traditional cordelette setup, tie it twice and you will end up with different loads on the pieces each time. So as a climber I must ask myself: how good is good enough? I'm not looking for the perfect anchor system. In the alpine, I generally eschew Cordelettes in favor of rope tie-in because of the time factor involved in setting up a cordelette anchor. OTOH, when leading the second pitch of Tempest on El Capitan, I set up a Cordelette system including screamers and sliding X components on my last good trio of pieces before an 80-foot section of hooking, heads and expando flakes, even though the belay was a long ways away from those pieces. For me, SRENE is the grail, but I never reach this golden chalice. When the placements are bad, I hedge my bets with more redundancy, with equalization. Ditto when the rock is bad. When the direction of loading is very predictable and the pieces are bombproof, I still go for redundancy (I am often known to back up multiple bolt belays with a piece or two when there are cracks handy, which happens more and more often these days) But worry less about equalization, i.e. I tend to use more "fixed length" legs to the belay setup. I confess to not having followed the anchor discussion closely to this point, having waited for the recent "recap" posts. And I confess that those recap posts have said nothing that will change the way I set up anchors, for now, in the real world. But I eagerly await further developments and testing that could produce a simple, lightweight and h#lla strong anchor that will never fail, and can also be used for rap slings, ascending a rope, extending to the ground from a too-short rap rope, looped around a 6' diameter pine or easily tied into improvised multi-step etriers. Staying tuned, Brutus
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billcoe_
Apr 7, 2006, 1:27 AM
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Like Brutus, didn't do the poll. Where was the "occasionally when the situation demands it" box? Like, you are guiding 5 beginners up to a relatively nice ledge and want clusterfrickage minimized. Generally, I always use the rope only for several reasons. Strength and speed. You can bang out a very strong, equalized anchor as fast as roping a steer: bang. You already are tied directly into the strongest cord available, why not use it. Plus, you do not have to carry a single use extra piece of gear which is un-necessary for a 2 or 3 man team (generally). Plus being old, I predate cordelettes and only found them useful when guiding. I often wondered why someone would fiddle with a weaker cord which they had to carry exclusively yet had no advantage to the rope. So I did it my way and some of my partners would do it theirs. It's all good really, don't fall onto the anchor eh? Old skool yet relavant? Old dogs, new tricks kind of situation. Kind of sad when you think of it. Better go drink some wine now before I start talking about gym climbers and 7 year olds out climbing me.
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buckyllama
Apr 7, 2006, 2:28 AM
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Jumping on the billcoe/brutus bandwagon here. Never done a wall so I won't speak to that, but I've only ever really used them when leading a group. One more unneaded chunk of gear. They are still useful in situations where redundency without equalization is adequate for safety and rope management is paramount. Sometimes speed and efficiency are more relevant to safety than absolute anchor strength. It's one more trick in the bag. Know the limitations and use accordingly.
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saxfiend
Apr 7, 2006, 3:27 AM
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In reply to: In reply to: So, any cordelette horror stories???!!! Like this one at Tahquitz? I've read that thread several times, and I've never seen anything there that gives conclusive proof the climbers were killed due to using a cordelette. The lab results posted by John Long are very persuasive, but I don't think you can cite the Tahquitz tragedy as a proven "cordelette horror story." JL
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mrpants
Apr 7, 2006, 1:03 PM
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In reply to: I'm amazed that it took you this long to figure out that the cordelette isn't perfect. I wasn't speaking for myself, but all those people that seem to have not figured it out despite the massive amounts of discussion being directly referenced in every thread that is coming up on the topic. More a comment on folks ability/willingness to wear blinders in order to protect what they believe in, despite evidence to contrary. I digress...
In reply to: But I eagerly await further developments and testing that could produce a simple, lightweight and h#lla strong anchor that will never fail, and can also be used for rap slings, ascending a rope, extending to the ground from a too-short rap rope, looped around a 6' diameter pine or easily tied into improvised multi-step etriers. Thanks for your post Brutus, it was a great and more deeply rooted in the reality of actual climbing than any theoretical discussion on equalization and redundancy (important as that conversation may be). Quick note...regarding your quote above, that's pretty much what the sliding x thread was trying to do. Not do away with the cord itself (cord being, as we know, the most useful thing in the galaxy after a towel), but to come up with a different configuration that would provide better equalization and/or redundancy but not be any more complex or require different or more gear. Anyway, that's my 2 cents. And Brutus, I hope you don't mind, but I plan to try and channel your elite wide skills on Steck-Salathe this May. Thanks for the inspiration.
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corpse
Apr 11, 2006, 2:15 PM
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I have used cordalette, but only other pplz - and only a few times.. I got turned to the good ol webolette a long time ago and have never turned back. It's 16 feet with extra large loops at both ends (great for accomodating 2 biners for a TR setup), it's quick and light, and easier to equalize 4 strands instead of 6! I also have a couple smaller 12' ones, but those have the more annoying smaller loops on the ends (which only really accomodate a single biner - my 16' I believe was custom made for a climbing shop near me).. They are rated at 22kn when doubled for an anchor, or 14kn single strand. Lightweight and strong, easy to untie any knots put in it. Only downside (after reading the sliding x thread), is that you can't do certain fancy equalization techniques that you can with the cordalette (speaking only in the aspect of creating a 3 point anchor - I'm sure there are ways with other anchors and techniques, not to be covered here). So in short, I have no plans of using a cordalette in day to day climbing, but do see it's purposes - it just doesn't have a purpose on MY rack.
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jimdavis
Apr 11, 2006, 4:02 PM
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In reply to: I have used cordalette, but only other pplz - and only a few times.. I got turned to the good ol webolette a long time ago and have never turned back. It's 16 feet with extra large loops at both ends (great for accomodating 2 biners for a TR setup), it's quick and light, and easier to equalize 4 strands instead of 6! I also have a couple smaller 12' ones, but those have the more annoying smaller loops on the ends (which only really accomodate a single biner - my 16' I believe was custom made for a climbing shop near me).. They are rated at 22kn when doubled for an anchor, or 14kn single strand. Lightweight and strong, easy to untie any knots put in it. Only downside (after reading the sliding x thread), is that you can't do certain fancy equalization techniques that you can with the cordalette (speaking only in the aspect of creating a 3 point anchor - I'm sure there are ways with other anchors and techniques, not to be covered here). So in short, I have no plans of using a cordalette in day to day climbing, but do see it's purposes - it just doesn't have a purpose on MY rack. rgold posted a way to use a webolette in an equalizing system. You clove it off, then rig a 3way sliding x below all of it. Jim
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corpse
Apr 11, 2006, 4:13 PM
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In reply to: rgold posted a way to use a webolette in an equalizing system. You clove it off, then rig a 3way sliding x below all of it. I musta missed it - and I've been looking for a way.. I've toyed with it, but couldn't get anything right that seemed solid that I would use.. Anyone got a link - I browsed through some of his posts, but couldn't (quickly) find it... I'll look more later if no one wants to make it easy on me :)
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pastprime
Apr 11, 2006, 5:31 PM
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A cordelette is a piece of gear. It can be rigged many ways. It causes confusion that the name has also come to be applied to one specific anchor configuration. John Long's test results show a particular anchor configuration doesn't equalize well. I'm surprized that surprizes anyone; but if I have three placements, each of which seems bombproof, I don't care if it equalizes. The only reason I don't just anchor off one of the pieces alone is the very slim chance that one piece is not as good as it looks. The chance of all three placements looking absolutely great, but being bad , is so slim I'm more worried about an earthquake breaking the wall off. If I don't have three placements I trust, I use an equalized system, maybe using my cordelette as part of the gear; and maybe with more than three pieces. As for using the rope for part of the anchor, that's fine if you know for sure how far it is to the next belay stance, but that's often not the way I climb. If I knew for sure I only needed 140 feet of my rope, I wouldn't have packed in an extra 60 feet of rope on an all day aproach in the first place. I'd bring a shorter rope and a 4ounce cordellete. As for the rope in the anchor being a shock absorber, that's why it is important to get the slack out of the anchor lines and to rig the belay and anchors so the belayer doesn't get moving and then get stopped suddenly by the anchor lines, and so the force passes from the rope to the belay device to the anchors, maybe moving the belayer some, but not passing through his or her body. I don't know that several very short strands of climbing rope in parallel absorb much shock anyway. Open for correction if they do.
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jimdavis
Apr 12, 2006, 2:04 AM
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In reply to: In reply to: rgold posted a way to use a webolette in an equalizing system. You clove it off, then rig a 3way sliding x below all of it. I musta missed it - and I've been looking for a way.. I've toyed with it, but couldn't get anything right that seemed solid that I would use.. Anyone got a link - I browsed through some of his posts, but couldn't (quickly) find it... I'll look more later if no one wants to make it easy on me :) http://www.rockclimbing.com/...p.cgi?Detailed=69926 All I know is RGold posted it before p.26...cause that's where I found the pic, with the rest of the pics from everything up to that point. Cheers, Jim
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mp29000
Apr 13, 2006, 3:21 PM
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personally I would never use this in the real world... too complicated and time consuming to justify... I continue to use the cordolette despite it's downfalls in bomber pice situations (i.e. 2 bolt anchor with a bomber bacup piece, or three bomber pieces that are god for a multi directional pull) I like the simplicity of the "improved sliding x" but have never even used that. Despite my long climbing career, I have not set a ton of gear anchors.
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corpse
Apr 13, 2006, 3:52 PM
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after toying a little - I think there's a big problem with that equalization method - unless I'm not seeing the picture right.. But it appears the lowest part of that sling goes through the gold biner, which is the same biner the rap rings go on.. During movement, the webbing can/will get pinched between the rap rings and the biner - which is going to make it not equalize very well (or not at all). I did a similiar setup in my basement, except I used biners instead of the rap rings - and definitely wasn't happy with the setup - maybe I set it up wrong with the equalization?
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catbird_seat
Apr 15, 2006, 1:03 AM
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In reply to: Hi, all: I only just received the initial data crunching and work ups from the statisticians, both nationally recognized PhD data wizards and experienced climbers. The drop tests themselves were conducted by the guy widely considerd the leading drop tester in the US, who has all the fancy UIAA drop towers and computer assist gear at his disposal. It took the poor guy weeks and hundreds of drop tests to finish the study. I can't post the actual graphs and box charts, nor yet the long lists of numbers. But I can quote an abridged version of a few paragraphs from the study that give a clear indication of how the cordelette performed under dynamic loading (factor one fall). These paragraphs concern the initial testing, done with the cordelette (in both equal and unequal arm length configurations) connecting only two primary anchor points. ------------- A. Cordelette, equal length: Tests simulating a factor 1 fall demonstrate that on average, a cordelette, equal length configuration generated an absolute difference in load that was a little less than 1 kN. Repeated measurements of the difference in the forces generated varied somewhat across multiple tests. Contrary to conventional wisdom and popular usage, the cordelette, with equal length arms is not a very effective system to achieve equalization. D. Cordelette, unequal length: This clearly-the-worst-configuration tested produces an absolute average difference in force between the anchor arms of almost 3.5 kN. Aside from generating the largest difference in force of the riggings measured, the cordelette, unequal length rigging was the most inconsistent when repeated measures of this difference was taken. In some cases, the difference in load measured was greater than 5 kN! To put it bluntly, the cordelette, unequal length configuration is the poorest performing anchor considered in all the testing conducted. Not only is equalization very poor, the degree of equalization varies wildly from fall to fall. This configuration is very unpredictable, except in that the difference in the forces generated from a fall will be high. The cordelette unequal length is simply to be avoided. Summary: While the equal armed cordelette distributes a dynamic load to an (barely) acceptable degree, and will no doubt remain a viable option in that configuration, a cordelette rigged with unequal arms is an inferior–and likely hazardous--choice when contrasted with the far more efficient load distribution of the sliding x and the equalette. John, nowhere do you describe what the angles are between the individual pieces. This greatly affects the load distribution. If the angle between each piece is relatively small, the direction from which the load comes can vary more and still distribute the load. The wider the angle the more critical it become to anticipate the direction of the load. The next factor that you did not mention is what type of cord was used. A 7 mm nylon cord will stretch more than a 5.5 mm Spectra cord. I would predict that the elastic cord will demonstrate the "unequal arm effect" to a much greater degree than the static cord. So it would be possible to get a wide variety of test results depending on all these varying factors.
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ihategrigris
Apr 15, 2006, 6:51 AM
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In reply to: John, nowhere do you describe what the angles are between the individual pieces. This greatly affects the load distribution. If the angle between each piece is relatively small, the direction from which the load comes can vary more and still distribute the load. The wider the angle the more critical it become to anticipate the direction of the load. The next factor that you did not mention is what type of cord was used. A 7 mm nylon cord will stretch more than a 5.5 mm Spectra cord. I would predict that the elastic cord will demonstrate the "unequal arm effect" to a much greater degree than the static cord. So it would be possible to get a wide variety of test results depending on all these varying factors. The elasticity of the material is not relevent to the result. Materials transmit force from one point to another through deformation; this is true in both 'static' (which is still somewhat dynamic) and dynamic set ups. It is important to note for further discussion that all materials are somewhat elastic, and do stretch. In the cordallet case, lets look at a simple example. Assuming the PP moves a fixed distance 'dx'. The arms of the cordallet must deform that same distance, no matter what the cord length. Assuming the elasticity of both arms is the same, the relative deformation of the shorter arm will be higher than that of the longer arm. Therefore, the tension of the shorter arm will be greater. Furthermore, assuming the elastic properties of the material remain constant during deformation, the force in the arm is directly proportional to it's length (the longer the arm, the less of the force it will carry). This remains true whether the material is an elastic band or a steel cable. So in-conclusion, the materials used for the cordallet teseted are not relevent, as all materials, no matter how 'static' will show this behavior in a test.
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catbird_seat
Apr 17, 2006, 11:18 PM
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You are just plain WRONG. An elastic cord can be thought of as a spring. Assume that the spring obeys Hook's Law that is xk=F where x is the displacement and k is a force constant, and F is the force exerted by the spring. The force constant for a cord is inversely proportional to the length of cord. If you have twice the cord, you have half the force constant. [Of course Hook's law assumes a linear response, which isn't actually true]. This should understood intuitively be most climbers who understand the concept of Fall Factor. For a given fall, doubling the amount of rope will halve the fall factor. Same is true for an elastic cordellette. for or a given displacement, if one leg is twice as long as the other, only half as much force will be transmitted by that leg compared to the short one. Of course, it isn't actually this simple, but to an approximation it is true. The anchor holding the short arm sees the larger impact force. It must.
In reply to: "relative deformation of the shorter arm will be higher than that of the longer arm. False. Both arms must deform to the same degree. They must. The shorter one deforms more relative to its length.
In reply to: Therefore, the tension of the shorter arm will be greater. True. Thank you. You made my point. More tension means more force on the anchor to which that arm is attached. Now what happens when you have a cordellette made out of a static material like Spectra? Not everyone knows this but Spectra is as low stretch as Kevlar. It has an elongation of 1% at 30% of its tensile strength. Perlon has, if I remember correctly, about 3-5% elongation. If you compare the RELATIVE stretch of different lengths of Spectra and Perlon it is obvious that there will be a larger amount of stretch. The Spectra will distribute the load more evenly between the two anchor points than the Perlon given the same angle between pieces but different arm lengths.
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ihategrigris
Apr 18, 2006, 3:03 AM
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In reply to: In reply to: "relative deformation of the shorter arm will be higher than that of the longer arm. False. Both arms must deform to the same degree. They must. The shorter one deforms more relative to its length. Now what happens when you have a cordellette made out of a static material like Spectra? Not everyone knows this but Spectra is as low stretch as Kevlar. It has an elongation of 1% at 30% of its tensile strength. Perlon has, if I remember correctly, about 3-5% elongation. If you compare the RELATIVE stretch of different lengths of Spectra and Perlon it is obvious that there will be a larger amount of stretch. The Spectra will distribute the load more evenly between the two anchor points than the Perlon given the same angle between pieces but different arm lengths. On the first point you misunderstand me. Both lengths will deform the SAME AMOUNT, however the shorter length will deform more relative to it's length. On the second point, i'm not too sure what your trying to say with your statement. If you hang 100 lbs off of two elastic bands, and another weight off of two steel cables, they will distribute the force in the same way (neglecting the effect of angles of course). Are you talking about mixing two materials in the anchor? If the whole anchor is built out of the same material, the only factor that changes the weight distribution is the final angle the cordallette arms end up at. I would argue that a difference of 1% to 3-5% for perlon is insignificant.
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jimdavis
Apr 18, 2006, 5:48 AM
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In reply to: You are just plain WRONG. An elastic cord can be thought of as a spring. Assume that the spring obeys Hook's Law that is xk=F where x is the displacement and k is a force constant, and F is the force exerted by the spring. The force constant for a cord is inversely proportional to the length of cord. If you have twice the cord, you have half the force constant. [Of course Hook's law assumes a linear response, which isn't actually true]. ... The Spectra will distribute the load more evenly between the two anchor points than the Perlon given the same angle between pieces but different arm lengths. And your answer is....BUZZZ! Wrong. Tech cord leads to a higher difference in force felt between the two legs of the anchor than nylon does...ie: worse equalization with a cordelette setup. John has stated this before in other threads, and it will be published in John's book. Let me say this again...without trying to use textbook physics to make my point. Cordelettes with master point knots, fixing the length of each arm...do not equalize well with unequal arm lengths (vertical crack setups). Nylon cord will distribute the force between the legs of the anchor better than tech cord will. The reason for this have been stated before, and will be stated again in John's book, I'm sure. I'm not gonna try and argue why myself, I'll f* it up trying to explain it. If you don't wanna belive me, don't. But take a look at Johns new book, once it hits the shelves. Cheers, Jim
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catbird_seat
Apr 18, 2006, 4:05 PM
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Jim, It's a complex issue. You have two factors to consider. 1) The angle beween the individual pieces. AND the angle of the load relative to each. 2) Differences in the length of the legs. Stretch in the cordellette mitigates inequalities in the first case. Legs with smaller angles will stretch to put more force on legs having larger angles. In the case where all legs have small angles relative to the load, then elasticity works against you in your quest to distribute loads equally. In the real world it may turn out that indeed Factor 1 greatly outweighs Factor 2.
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ihategrigris
Apr 19, 2006, 1:02 AM
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In reply to: And your answer is....BUZZZ! Wrong. Tech cord leads to a higher difference in force felt between the two legs of the anchor than nylon does...ie: worse equalization with a cordelette setup. John has stated this before in other threads, and it will be published in John's book. Let me say this again...without trying to use textbook physics to make my point. Cordelettes with master point knots, fixing the length of each arm...do not equalize well with unequal arm lengths (vertical crack setups). Nylon cord will distribute the force between the legs of the anchor better than tech cord will. The reason for this have been stated before, and will be stated again in John's book, I'm sure. I'm not gonna try and argue why myself, I'll f* it up trying to explain it. If you don't wanna belive me, don't. But take a look at Johns new book, once it hits the shelves. Cheers, Jim You owe at least a link to something backing up your argument. This is of course looking at a corallette, webolette, etc with a fixed power point knot. I'm talking talking about the actual distribution of force (say 20% to one point, 80% to another). In the static case (in the final rest position) the distribution should only be dependant on the geometry of the anchor, and not on the material. In the dynamic case, obviously, the more elastic material will transfer less force to both anchor points, and the net froce difference will be lower because of this. That being said, the percent distribution of force should be independent of material, and dependent only on geometry, as in the static case. so what am I missing here?
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jimdavis
Apr 19, 2006, 2:05 AM
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In reply to: You owe at least a link to something backing up your argument. so what am I missing here? Just take a look at John's posts in the various threads. He's come right out and said that nylon gives a better force distribution than tech cord in an cordelette configuration. I forget where it was, but I'm sure you can find it just like I did. Jim
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anchorhead
Apr 21, 2006, 3:48 PM
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Some of the recent posts attempt to model the tether material as linear springs. That's a critical simplification. If the tethers were truly linear springs, then we would typically see a fairly reasonable distribution from leg to leg, typically a 1 : 2 : 1 distribution or less. I'd be glad to explain that if anyone wants to be bored with the math (eeeks - cosines!). The real issue in my mind is that the stretch of most tether materials used in climbing are not linear. A while back I measured the stretch of some of my favorite climbing materials under static loads. Not to pick on Titan Spectra Cord, but this stuff stretches relatively easily and linearly up to about 150 lbf, then it gets very stiff. The one leg that takes the most force, usually the center one in a 3-leg cordelette setup, reaches that 150 lbf point quicker than the other 2 legs. Any additional force applied to the anchor system will result in very small additional movement in the power point. As a result, the outer legs which are still in their 'stretchy' phase will experience minimal additional force. The center leg is not totally stiff, so a large enough load will move the power point enough to impose 150lbf on the outer tethers, at which time any further load will be distributed more reasonably. I've done some computer modeling of anchor systems, and one of the models showed that a 3-anchor cordelette results in about a 1 : 2 : 1 distribution of force under small loads, but something closer to 1 : 9 : 1 distribution under around 1000 lbf loads. This particular simulation was done on a cordelette anchor system on a flat wall with 45 degree angles between the tethers and with the direction of pull in line with the center tether. I'd caution everyone that this was just based on a simulation. I am anxiously awaiting JL's book to see how far off my simulations are. One last point. I have to agree with Craig Connally regarding the importance of security vs strength. Most of the time the distribution of force is not important. But on snow, ice, aid gear, or when you're trapped with no means of secure protection, it's good to know what's going on.
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catbird_seat
Apr 21, 2006, 6:01 PM
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Let us suppose that some of us would like to continue to use the cordellette in the tied-off mode, that is, with static equalization, the "traditional" configuration. Given what has been learned, what would you do differently in the way you set up the anchor? Let's call this an interim solution pending the release of John's new book. We know that unequal lengths are worse than equal lengths with regard to the individual legs. Vertical cracks by their very geometry tend to lead to unequal lengths. This is because we prefer to hang below our anchor point. There are more points above us than below us. The upper legs tend to be longer so the bottom tends to take most of the load. What can we do to reduce unequal lengths? 1) Minimize the angle between pieces. I would say that the 45 degree angle mentioned above would be the extreme case for me. I try to keep it smaller than that. 2) Build the anchor with the pieces arrayed horizontaly whenever possible. 3) If you can't do (1) or (2), then use dyneema runners to extend from the individual piece to reduce the unequalness. What else?
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jimdavis
Apr 21, 2006, 6:21 PM
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In reply to: Given what has been learned, what would you do differently in the way you set up the anchor? Let's call this an interim solution pending the release of John's new book. Use John's Equalette, or Duo-Glide setup. For a three piece anchor..clip one loop to the strongest piece, tie 2 overhand limiter knots...then close the other side of the cordelette to each piece with a single strand. Put a HMS biner in on a Magic X, or use a locker on each strand between the limiter knots...and rig everything off those biners (<< this is my opinion, not John's recommendatation...as far as I know) You'll get teriffic load distribution between 2 pieces, with a 3rd stepping in if the load shifts or 1 piece fails. I'm pretty sure this is still the best way to use a cordelette for a 3 piece vertical anchor...unless these "troublettes" are testing out well. Maybe Craig has something to add on that. Cheers, Jim
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catbird_seat
Apr 21, 2006, 6:35 PM
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You didn't answer my question. You are talking about an entirely new way of using the cordellette. It may be the way to go, but just for the sake of argument let's focus on the statically equalized design. Let's say we are not using Equallettes or Sliding X's. Okay?
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mrpants
Apr 21, 2006, 8:37 PM
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In reply to: Let us suppose that some of us would like to continue to use the cordelette in the tied-off mode, that is, with static equalization, the "traditional" configuration. Given what has been learned, what would you do differently in the way you set up the anchor? Let's call this an interim solution pending the release of John's new book. The reason behind all of these threads and conversations has been that JL states he has conclusive, verifiable and soon-to-be-published test results that using a cordelette to statically equalize anything other than two bolt-strength anchors located horizontal from one another doesn't work. Except for the two bolt scenario, any configuration of anchors, angles, strand lengths, etc results in something that is subject to widely variable and unpredictable forces. It sounds to me like you want to try and approximate this ideal two-bolt situation by tweaking your anchor points, angles and heights. I very much doubt this is a realistic solution, particularly as you add slings per your earlier suggestion...this just adds more variability. So is this really worth the time? In real-life is it even reasonably possible? The great thing about cordelettes as we used to believe they worked was you could *quickly* equalize your points...no need for the readjustments you suggest. Once you start needing to futz around that much, the idea of using a cordelette to statically equalize becomes much less efficient and much more time consuming. Not to mention that it never will reliably equalize anyway. Better to find a new way, or go back to more traditional methods that have been used for decades. Seems like you a trying to plug holes in a sinking ship because...well, I'm not sure why.
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sterlingjim
Apr 21, 2006, 9:03 PM
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It appears that 71% of the responders just don't get it. :wink:
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tradklime
Apr 21, 2006, 11:43 PM
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In reply to: It appears that 71% of the responders just don't get it. :wink: I think you mean 81%, and I agree with your sentiment.
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roy_hinkley_jr
Apr 22, 2006, 12:15 AM
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And 71% of that 81% started climbing after the cordedeath was introduced. They all think it's ancient history and well tested when actually it is neither.
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jimdavis
Apr 22, 2006, 12:29 AM
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In reply to: You didn't answer my question. You are talking about an entirely new way of using the cordellette. It may be the way to go, but just for the sake of argument let's focus on the statically equalized design. Let's say we are not using Equallettes or Sliding X's. Okay? Your joking right? Your requesting that we fix a problem, without elimination the root of it. Static equalization is the problem...There's nothing to argue about. You asked how do we fix the problem of unequal load distribution... this is how to rig an anchor still using the same cord. Dunno what else your expecting.... Jim
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anchorhead
Apr 22, 2006, 3:35 AM
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In reply to: Let us suppose that some of us would like to continue to use the cordellette in the tied-off mode, that is, with static equalization, the "traditional" configuration. Given what has been learned, what would you do differently in the way you set up the anchor? Let's call this an interim solution pending the release of John's new book. We know that unequal lengths are worse than equal lengths with regard to the individual legs. Vertical cracks by their very geometry tend to lead to unequal lengths. This is because we prefer to hang below our anchor point. There are more points above us than below us. The upper legs tend to be longer so the bottom tends to take most of the load. What can we do to reduce unequal lengths? 1) Minimize the angle between pieces. I would say that the 45 degree angle mentioned above would be the extreme case for me. I try to keep it smaller than that. 2) Build the anchor with the pieces arrayed horizontaly whenever possible. 3) If you can't do (1) or (2), then use dyneema runners to extend from the individual piece to reduce the unequalness. What else? Here's an idea. I posted a picture to this site titled "cordelette w better static equalization". Once approved I hope I can add a link to it. In lieu of that, words will have to do. Don't pre-tie your accessory cord. Tie one end to the center anchor with your knot of choice, string the outer anchors as you normally do with a cordelette, and tie your power point. You'll end up with one strand going to the center anchor, 2 strands to each of the outer anchors, and a loose tail hanging out of the power point knot. The loose tail can be tied to a second center anchor if you want to make a 4-anchor system. This should
1) improve on the distribution of forces considerably. 2) let you use your 20 ft accessory cord for other purposes such as rescue, hauling packs, or helping a neophyte over a scramble crux. That double fisherman is a bear to untie. BTW, like everything in climbing you have to make tradeoffs. The advantage of 45 degree legs is that you can spread out your anchors a bit more to improve the diversity on the rock, if that's what you want to optimize. The well known disadvantage is the increase in force on the outer anchors if the center anchor(s) fail. It all depends on what you're trying to protect against.
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jimdavis
Apr 22, 2006, 4:07 AM
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In reply to: Here's an idea. I posted a picture to this site titled "cordelette w better static equalization". Once approved I hope I can add a link to it. In lieu of that, words will have to do. Don't pre-tie your accessory cord. Tie one end to the center anchor with your knot of choice, string the outer anchors as you normally do with a cordelette, and tie your power point. You'll end up with one strand going to the center anchor, 2 strands to each of the outer anchors, and a loose tail hanging out of the power point knot. The loose tail can be tied to a second center anchor if you want to make a 4-anchor system. This should 1) improve on the distribution of forces considerably. 2) let you use your 20 ft accessory cord for other purposes such as rescue, hauling packs, or helping a neophyte over a scramble crux. That double fisherman is a bear to untie. BTW, like everything in climbing you have to make tradeoffs. The advantage of 45 degree legs is that you can spread out your anchors a bit more to improve the diversity on the rock, if that's what you want to optimize. The well known disadvantage is the increase in force on the outer anchors if the center anchor(s) fail. It all depends on what you're trying to protect against. http://www.umit.maine.edu/..._small.JPG?WasRead=1 here ya go! Jim
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sterlingjim
Apr 23, 2006, 3:10 AM
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In reply to: I think you mean 81%, and I agree with your sentiment. I suppose you're right. I was just giving that middle 10% the benefit of the doubt. I don't like the last two choices much though. How about 'one probably won't die using it but one should use something else.'? I used a cordelette once and thought 'damn, this is a waist of time' and chucked it off the cliff. OK, I didn't actually chuck it off the cliff but I gave it away then and there.
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clmbnski
Apr 23, 2006, 7:02 PM
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Well after all the talk I am still unconvinced that the cordelette tied in its traditional configuration is as horrible as some people make it out to be. I do use a slightly different system now though. If there are pieces in my anchor that are lower strength like smaller nuts,cams, ect. I connect them with the magic x and then incorporate that into the rest of the anchor making a sort of hybrid. Sorry to those who want different poll options, but I am not going to change it because last time it messed the poll up for a week. Besides I think the current choices are pretty representative.
In reply to: I used a cordelette once and thought 'damn, this is a waist of time' and chucked it off the cliff. OK, I didn't actually chuck it off the cliff but I gave it away then and there. :roll:
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jimdavis
Apr 23, 2006, 7:26 PM
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In reply to: Well after all the talk I am still unconvinced that the cordelette tied in its traditional configuration is as horrible as some people make it out to be. So why start this thread, then? You've had John Long, and Jim Ewing step in and flat out tell you the cordelette sucks. There is no-one else closer to this research, and it's implications, than these 2 guys right here. If your not going to take the word of the 2 guys that actually performed the research...what the hell are you going to believe? Jim
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clmbnski
Apr 23, 2006, 8:08 PM
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In reply to: If your not going to take the word of the 2 guys that actually performed the research...what the hell are you going to believe? John Long and Jim Ewing definitely have credibility, and are worth listening to but I am not going to come to the same conclusions until see more data, because that is just the way I am. So far I have seen about a three sentence summary of the testing data. What would convince me is somesort of technical writeup, as someone else also requested, detailing methods, raw data, discussion ect. If that has been posted already let me know. Am I the only one who thinks being skeptical is a good thing? Isnt that what science is all about, not just taking something on faith but saying show me your evidence. When you are taking physics or chemistry or any other class the instructor doesnt just say "well this is the way it is" but rather why and how it came to be. The point is that just telling me is not going to convince me.
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jimdavis
Apr 23, 2006, 8:45 PM
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In reply to: In reply to: If your not going to take the word of the 2 guys that actually performed the research...what the hell are you going to believe? John Long and Jim Ewing definitely have credibility, and are worth listening to but I am not going to come to the same conclusions until see more data, because that is just the way I am. So far I have seen about a three sentence summary of the testing data. What would convince me is somesort of technical writeup, as someone else also requested, detailing methods, raw data, discussion ect. If that has been posted already let me know. Am I the only one who thinks being skeptical is a good thing? Isnt that what science is all about, not just taking something on faith but saying show me your evidence. Care to show the evidence you used to determine that the cordelette works well? I mean, if your such a skeptic...and won't do anything until you see the hard data on it...what'd you base your descission to use a cordelette off of? Johns evidence should be written up in his book...guess you'll have to wait till then to see the numbers...just like the rest of us. In the mean time, why would John and Jim stake their names on something they can't proove? Jim
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roy_hinkley_jr
Apr 23, 2006, 11:33 PM
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In reply to: Am I the only one who thinks being skeptical is a good thing? Isnt that what science is all about, not just taking something on faith but saying show me your evidence. When you are taking physics or chemistry or any other class the instructor doesnt just say "well this is the way it is" but rather why and how it came to be. The point is that just telling me is not going to convince me. Yet you blindly accepted the untested cordadeath :roll:
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tradmanclimbs
Apr 24, 2006, 12:02 AM
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John allready did stake his name on something he did not prove. John was the one who convinced us all to use the cordelette in the first place 8^)
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clmbnski
Apr 24, 2006, 1:15 AM
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In reply to: Yet you blindly accepted the untested cordadeath Rolling Eyes Well it has been used widely and is included in almost any climbing publication Freedom of the Hills, Self Rescue, even on Sterling's website. So in a sense it has been tested. I know, its thought that factor two falls onto it rarely occur, and that is why it is good that there has been this new testing that we are all arguing about. I have an open mind and will get the new anchor book when it comes out but the arguments I have seen against it on this website do not convince me that one should not use a cordelette. Evidence that it works well: (And I am not saying it should be used all the time in every situation, but in general...) -It is widely used and has been for some time -It is very versatile and can be used in many different ways including self rescue -It is quick and clean eliminating clusterfk As far as SRENE goes I realize it has equilization problems but will conclude on the extent of the problem when I see the data. If the new equalette or something similar can perform in a similar manner than I am all for it. Chris
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catbird_seat
Apr 24, 2006, 7:03 PM
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In reply to: In reply to: Here's an idea. I posted a picture to this site titled "cordelette w better static equalization". Once approved I hope I can add a link to it. In lieu of that, words will have to do. Don't pre-tie your accessory cord. Tie one end to the center anchor with your knot of choice, string the outer anchors as you normally do with a cordelette, and tie your power point. You'll end up with one strand going to the center anchor, 2 strands to each of the outer anchors, and a loose tail hanging out of the power point knot. The loose tail can be tied to a second center anchor if you want to make a 4-anchor system. This should 1) improve on the distribution of forces considerably. 2) let you use your 20 ft accessory cord for other purposes such as rescue, hauling packs, or helping a neophyte over a scramble crux. That double fisherman is a bear to untie. BTW, like everything in climbing you have to make tradeoffs. The advantage of 45 degree legs is that you can spread out your anchors a bit more to improve the diversity on the rock, if that's what you want to optimize. The well known disadvantage is the increase in force on the outer anchors if the center anchor(s) fail. It all depends on what you're trying to protect against. http://www.umit.maine.edu/..._small.JPG?WasRead=1 here ya go! Jim This is exactly the sort of thing I was interested in. People are fond of saying now that the power point tie-off method was never tested, by which they mean it was never subjected to rigorous scientific study. In a sense though, it has been tested empirically by untold thousands of climbers in everyday use. The number of climbers who have died from anchor failure has been very small compared to other causes. If one could make some minor improvements to something that is arguably safe, why not?
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jimdavis
Apr 25, 2006, 1:54 AM
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^^As someone else on this site put it: preventative medicine. If you owned a car that had a potential issue with the airbag deploying...wouldn't you want it recalled? You still need to f* up (get in an accident in the first place) and you have a good ole seat belt, too...so it's no big deal, right? But you'd rather stack all the odds in your favor...wouldn't you? Just my take on it... Cheers, Jim
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