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jberk
Jun 9, 2013, 12:01 AM
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Hey I was wondering if it is safe to use an EDK (backed up with a second EDK) in a cordelette anchor toprope? I know that I can use a double fishermans but it tends to be a real pain to untie if weighted. Thanks.
(This post was edited by jberk on Jun 9, 2013, 12:14 AM)
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billl7
Jun 9, 2013, 1:34 AM
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jberk wrote: Hey I was wondering if it is safe to use an EDK (backed up with a second EDK) in a cordelette anchor toprope? I know that I can use a double fishermans but it tends to be a real pain to untie if weighted. Thanks. Is this to tie the cordelette in a loop? Or something else?
(This post was edited by billl7 on Jun 9, 2013, 1:34 AM)
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dagibbs
Jun 9, 2013, 1:52 AM
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Assuming you're trying to make a loop, yes an over-hand knot (AKA an EDK), backed up with another over-hand knot will work quite fine. If they've been weighted a time or two, they also get hard to untie, of course.
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jberk
Jun 9, 2013, 2:20 AM
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billl7 wrote: jberk wrote: Hey I was wondering if it is safe to use an EDK (backed up with a second EDK) in a cordelette anchor toprope? I know that I can use a double fishermans but it tends to be a real pain to untie if weighted. Thanks. Is this to tie the cordelette in a loop? Or something else? Yup, tying to ends of my cordelette together.
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billl7
Jun 9, 2013, 2:27 AM
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jberk wrote: billl7 wrote: jberk wrote: Hey I was wondering if it is safe to use an EDK (backed up with a second EDK) in a cordelette anchor toprope? I know that I can use a double fishermans but it tends to be a real pain to untie if weighted. Thanks. Is this to tie the cordelette in a loop? Or something else? Yup, tying to ends of my cordelette together. ... and there are many ways to use a cordelette for a top rope anchor. Sometimes, one can even rig the anchor with it without directly joining the two ends together. What's your plan? Bill L
(This post was edited by billl7 on Jun 9, 2013, 2:30 AM)
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jberk
Jun 9, 2013, 2:43 AM
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billl7 wrote: jberk wrote: billl7 wrote: jberk wrote: Hey I was wondering if it is safe to use an EDK (backed up with a second EDK) in a cordelette anchor toprope? I know that I can use a double fishermans but it tends to be a real pain to untie if weighted. Thanks. Is this to tie the cordelette in a loop? Or something else? Yup, tying to ends of my cordelette together. ... and there are many ways to use a cordelette for a top rope anchor. Sometimes, one can even rig the anchor with it without directly joining the two ends together. What's your plan? Bill L I am a little confusing what you mean. I am building an anchor out of three pieces of trad. Does this answer your question? Thanks.
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billl7
Jun 9, 2013, 2:47 AM
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jberk wrote: billl7 wrote: jberk wrote: billl7 wrote: jberk wrote: Hey I was wondering if it is safe to use an EDK (backed up with a second EDK) in a cordelette anchor toprope? I know that I can use a double fishermans but it tends to be a real pain to untie if weighted. Thanks. Is this to tie the cordelette in a loop? Or something else? Yup, tying to ends of my cordelette together. ... and there are many ways to use a cordelette for a top rope anchor. Sometimes, one can even rig the anchor with it without directly joining the two ends together. What's your plan? Bill L I am a little confusing what you mean. I am building an anchor out of three pieces of trad. Does this answer your question? Thanks. Configured roughly like this?
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jberk
Jun 9, 2013, 2:51 AM
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billl7 wrote: jberk wrote: billl7 wrote: jberk wrote: billl7 wrote: jberk wrote: Hey I was wondering if it is safe to use an EDK (backed up with a second EDK) in a cordelette anchor toprope? I know that I can use a double fishermans but it tends to be a real pain to untie if weighted. Thanks. Is this to tie the cordelette in a loop? Or something else? Yup, tying to ends of my cordelette together. ... and there are many ways to use a cordelette for a top rope anchor. Sometimes, one can even rig the anchor with it without directly joining the two ends together. What's your plan? Bill L I am a little confusing what you mean. I am building an anchor out of three pieces of trad. Does this answer your question? Thanks. Configured roughly like this? [image]http://www.chockstone.org/TechTips/Cordelette6l.JPG[/image] Exactly, if you swap out the runner for a chordelette.
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billl7
Jun 9, 2013, 3:00 AM
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Well, if you really need to not have a knot there when you're done for the day and if your cord is long enough ... * pretend there is a fourth piece of gear; * when you thread the cord through the pieces, leave the two ends in the vicinity of the imaginary fourth piece; * tie the power point's knot as shown in the picture. The two ends are then isolated from any load by the power point's knot. You can tie them together however you like and it does not matter or leave them free. They will never see a load. Bill L P.S. Personally, I just tie the double fishermans and rarely untie it.
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jberk
Jun 9, 2013, 3:09 AM
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billl7 wrote: Well, if you really need to not have a knot there when you're done for the day and if your cord is long enough ... * pretend there is a fourth piece of gear; * when you thread the cord through the pieces, leave the two ends in the vicinity of the imaginary fourth piece; * tie the power point's knot as shown in the picture. The two ends are then isolated from any load by the power point's knot. You can tie them together however you like and it does not matter or leave them free. They will never see a load. Bill L P.S. Personally, I just tie the double fishermans and rarely untie it. This sounds like a great option, but I am concerned with how much tail I would have to leave if I dont knot the chordelette. Plus there is something psychologically screaming at me when I conceptualize an open ended rope on an anchor, regardless of how safe it is. I like the idea of a permanent double fisherman's but at enchanted rock I often need to tie anchors using a bowline knot. Do you have any other suggestions? Are you deliberately staying away from the double EDK because your concerned with its safety?
(This post was edited by jberk on Jun 9, 2013, 3:13 AM)
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billl7
Jun 9, 2013, 3:15 AM
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jberk wrote: Are you breathlessly staying away from the double EDK because your concerned with its safety? Yes, I stay away from it for that application because many of my anchors are high above the deck. There are much stronger knots. Bill L Edit: What I mean is ... high above the deck where I want them to be able to withstand a leader fall right onto the anchor.
(This post was edited by billl7 on Jun 9, 2013, 3:20 AM)
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jt512
Jun 9, 2013, 6:28 AM
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jberk wrote: Hey I was wondering if it is safe to use an EDK (backed up with a second EDK) in a cordelette anchor toprope? I know that I can use a double fishermans but it tends to be a real pain to untie if weighted. Thanks. I don't know whether it's safe or not, but I know it's foolish. The double fisherman's knot tightens under tension, which is exactly the behavior you want in a cordelette knot. And, no, it is not significantly more difficult to untie after it has been weighted. Stick with time-tested methods. Resist the temptation to gumby innovate.
(This post was edited by jt512 on Jun 9, 2013, 6:28 AM)
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jberk
Jun 9, 2013, 6:43 AM
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jt512 wrote: jberk wrote: Hey I was wondering if it is safe to use an EDK (backed up with a second EDK) in a cordelette anchor toprope? I know that I can use a double fishermans but it tends to be a real pain to untie if weighted. Thanks. I don't know whether it's safe or not, but I know it's foolish. The double fisherman's knot tightens under tension, which is exactly the behavior you want in a cordelette knot. And, no, it is not significantly more difficult to untie after it has been weighted. Stick with time-tested methods. Resist the temptation to gumby innovate. I do agree that the double fisherman's is safer but I strongly disagree that it is as easy to untie. This is not only my personal experience but reiterated in almost every guidebook and knot tying website. http://www.animatedknots.com even gos so far to say that the two ends can effectively become "welded". It can be extremely foolish for me to risk my cordelette locking up on a multi-pitch especially if I later need to tie a bowline on a later pitch if an overhand backed up with an overhand will suffice. Of course that is the big question that I am trying to figure out.
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swaghole
Jun 9, 2013, 11:01 AM
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jberk wrote: I do agree that the double fisherman's is safer but I strongly disagree that it is as easy to untie. This is not only my personal experience but reiterated in almost every guidebook and knot tying website. http://www.animatedknots.com even gos so far to say that the two ends can effectively become "welded". It can be extremely foolish for me to risk my cordelette locking up on a multi-pitch especially if I later need to tie a bowline on a later pitch if an overhand backed up with an overhand will suffice. Of course that is the big question that I am trying to figure out. Instead of climbing wiht a cordelette that is tied in a loop, you could try building your anchors with a cordelette that is not looped but instead has figure 8s tied at each end. It is just as versatile as a looped cordelette and can be easily configured to join a 3 or 4 piece anchor or can be doubled up for redundancy. In this configuration, the cordelette can be used setting up pulley systems or, in your case, for tying your bowline when needed. If you really must undo all knots, the figure 8 does come undone more easily than a double-fisherman (IMO), even more if you use a Yosemite finish. Just my 2 cents...
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padlinfool
Jun 9, 2013, 1:51 PM
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swaghole wrote: Instead of climbing wiith a cordalette that is tied in a loop, you could try building your anchors with a cordalette that is not looped but instead has figure 8s tied at each end. The above method will not equalize the pieces well as most of the load will be transferred to the piece with the double strand. The single strands will stretch more because there is less material on those legs. You could just NOT tie the cordelette into a loop.... by pulling the loose ends through the one main knot. Pretty easy to do. -Grab both ends together (creating an imaginary loop). -Clip your pieces and pull down the loops to your loose ends. You can adjust the length of the loops by pulling slack on loose ends(great feature). -Tie your knot (8 or overhand) with the loops and loose ends. -Tighten and dress....even the loose ends You will end up with double strands to all pieces (with no knots), a big knot, 2 loop masterpoint (for a 3 piece anchor) plus the loose ends exiting from the bottom of the knot. Credit to knudenoggin for this concept.
(This post was edited by padlinfool on Jun 9, 2013, 1:56 PM)
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acorneau
Jun 9, 2013, 2:33 PM
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padlinfool wrote: swaghole wrote: Instead of climbing wiith a cordalette that is tied in a loop, you could try building your anchors with a cordalette that is not looped but instead has figure 8s tied at each end. The above method will not equalize the pieces well as most of the load will be transferred to the piece with the double strand. The single strands will stretch more because there is less material on those legs. You're missing the concept of clipping the two ends to the same piece and then continuing the regular cordelette system as usual. That yields the same result as a looped cord but without actually having the two ends tied together.
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bearbreeder
Jun 9, 2013, 2:40 PM
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padlinfool wrote: swaghole wrote: Instead of climbing wiith a cordalette that is tied in a loop, you could try building your anchors with a cordalette that is not looped but instead has figure 8s tied at each end. The above method will not equalize the pieces well as most of the load will be transferred to the piece with the double strand. The single strands will stretch more because there is less material on those legs.. equalization is basically a myth with cords anchors anyways, especially if every leg is not exactly the same length the advantage of the doubled strand is that you can choose which piece likely sees the most load for the OP ... it all depends on how you use the cord ... if you arent tying off the masterpoint with a big knot, ie, you cant with a big tree anchor/bolder ... the overhand can capsize at lower loads than the fishermans ... if however youre doing it the same way as shown in this video then yr fine ... as its the big masterpoint knot that keeps then strand toghether http://www.youtube.com/watch?v=qF4A85CPr8c with thinner techcord and other such ... use a triple fishermans
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jberk
Jun 9, 2013, 3:33 PM
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bearbreeder wrote: padlinfool wrote: swaghole wrote: Instead of climbing wiith a cordalette that is tied in a loop, you could try building your anchors with a cordalette that is not looped but instead has figure 8s tied at each end. The above method will not equalize the pieces well as most of the load will be transferred to the piece with the double strand. The single strands will stretch more because there is less material on those legs.. equalization is basically a myth with cords anchors anyways, especially if every leg is not exactly the same length the advantage of the doubled strand is that you can choose which piece likely sees the most load for the OP ... it all depends on how you use the cord ... if you arent tying off the masterpoint with a big knot, ie, you cant with a big tree anchor/bolder ... the overhand can capsize at lower loads than the fishermans ... if however youre doing it the same way as shown in this video then yr fine ... as its the big masterpoint knot that keeps then strand toghether http://www.youtube.com/watch?v=qF4A85CPr8c with thinner techcord and other such ... use a triple fishermans My only concern with this method (video) is that it looks like it can be easy to miss tie. One of the reasons i like the overhand/edk backed up with another overhand is that you could do it in your sleep. When you say the "overhand capsizes at lower loads" does this include a backed up overhand knot? I have a 6mm powercord cordelette and leave about 6inch of tail with the backed up overhand. Is this safe?
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bearbreeder
Jun 9, 2013, 4:20 PM
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for power cord, if its spectra/dyneema id use a tripple fishermans ...realistically unless you need to keep untie and retying it to sling trees/boulders, you arent going to untie it that much or tie fig8s/tripple barrels at each end and use the cord like this ... put the doubled strand on the strongest piece dont overthink it ...
(This post was edited by bearbreeder on Jun 9, 2013, 4:27 PM)
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jt512
Jun 9, 2013, 5:34 PM
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swaghole wrote: jberk wrote: I do agree that the double fisherman's is safer but I strongly disagree that it is as easy to untie. This is not only my personal experience but reiterated in almost every guidebook and knot tying website. http://www.animatedknots.com even gos so far to say that the two ends can effectively become "welded". It can be extremely foolish for me to risk my cordelette locking up on a multi-pitch especially if I later need to tie a bowline on a later pitch if an overhand backed up with an overhand will suffice. Of course that is the big question that I am trying to figure out. Instead of climbing wiht a cordelette that is tied in a loop, you could try building your anchors with a cordelette that is not looped but instead has figure 8s tied at each end.. Ah, yes, the ol' deatholette resurfaces. It has half the strength of a cordelette tied in a loop.
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swaghole
Jun 9, 2013, 6:03 PM
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jt512 wrote: swaghole wrote: jberk wrote: I do agree that the double fisherman's is safer but I strongly disagree that it is as easy to untie. This is not only my personal experience but reiterated in almost every guidebook and knot tying website. http://www.animatedknots.com even gos so far to say that the two ends can effectively become "welded". It can be extremely foolish for me to risk my cordelette locking up on a multi-pitch especially if I later need to tie a bowline on a later pitch if an overhand backed up with an overhand will suffice. Of course that is the big question that I am trying to figure out. Instead of climbing wiht a cordelette that is tied in a loop, you could try building your anchors with a cordelette that is not looped but instead has figure 8s tied at each end.. Ah, yes, the ol' deatholette resurfaces. It has half the strength of a cordelette tied in a loop. If you use it doubled-up, why would it be half the strength?
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jberk
Jun 9, 2013, 7:14 PM
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bearbreeder wrote: for power cord, if its spectra/dyneema id use a tripple fishermans ...realistically unless you need to keep untie and retying it to sling trees/boulders, you arent going to untie it that much or tie fig8s/tripple barrels at each end and use the cord like this ... put the doubled strand on the strongest piece [image]http://www.supertopo.com/photos/4/72/168688_20031_XL.jpg[/image] dont overthink it ... So the cordelette is not dyneema its good old fashioned nylon. I do tend to need to tie it around rocks (I do trad climbing at enchanted rock) so I do have to be able to have both ends accessible for a bowline. I have never seen the tripple barrels used in an anchor and it does look quite safe and redundant, but I have read in a bunch of guidebooks that you do loose a good amount of strength if the cordelette is not tied. It does concern me though that I am opening up another possible failure knot (2 ends as opposed to the ends tied together). I am looking for something bomber. I cant seem to find a good amount of studies on the EDK and the ones I do find do not test it with it backed up with an overhand. Maybe its just because I am new to climbing and just have to accept that there is no 100% when it comes to climbing.
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rgold
Jun 9, 2013, 7:28 PM
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If you are setting up toprope anchors, then you really ought to be using larger-diameter rope or wider webbing than is typically used for a cordelette, and you wouldn't typically keep such materials knotted. If you are speaking of trad anchors, then you can almost always use the climbing rope itself to tie into large rocks and trees. Conclusion: the only time you really have to untie a cordelette is either for rescue and/or emergency retreat purposes, in which case cutting off the knot is probably the best thing to do. In view of these considerations, I'd use a double fisherman's. It is compact, strong, and it won't work loose when you aren't looking.
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jberk
Jun 9, 2013, 7:37 PM
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rgold wrote: If you are setting up toprope anchors, then you really ought to be using larger-diameter rope or wider webbing than is typically used for a cordelette, and you wouldn't typically keep such materials knotted. If you are speaking of trad anchors, then you can almost always use the climbing rope itself to tie into large rocks and trees. Conclusion: the only time you really have to untie a cordelette is either for rescue and/or emergency retreat purposes, in which case cutting off the knot is probably the best thing to do. In view of these considerations, I'd use a double fisherman's. It is compact, strong, and it won't work loose when you aren't looking. So I do switch often between using my cordelette as a normal 3 point anchor and using it with a boline around a fixed point plus another anchor. I do need the flexibility. Honestly I am not woried about gear failure. The cord is rated at 19KN (4,800LBS) and is think enough that I am not concerned about friction.
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rgold
Jun 9, 2013, 7:51 PM
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If you've convinced yourself that you need the flexibility to untie your cordelette so that you can use it to put a bowline around a "fixed point," then nothing anyone can say is going to do much good. My point was that you don't need this "flexibility" at all (generations of highly experienced climbers have climbed their entire careers without ever once having to do this) and so you might as well just knot your cordelette with a strong secure knot and cut it off if an emergency arises and you need your cordelette for rappel slings, for example. But to give you the benefit of the doubt, perhaps you'd like to post a picture of a situation that requires you to untie the cordelette and then retie it with a bowline?
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jberk
Jun 9, 2013, 8:02 PM
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rgold wrote: If you've convinced yourself that you need the flexibility to untie your cordelette so that you can use it to put a bowline around a "fixed point," then nothing anyone can say is going to do much good. My point was that you don't need this "flexibility" at all (generations of highly experienced climbers have climbed their entire careers without ever once having to do this) and so you might as well just knot your cordelette with a strong secure knot and cut it off if an emergency arises and you need your cordelette for rappel slings, for example. But to give you the benefit of the doubt, perhaps you'd like to post a picture of a situation that requires you to untie the cordelette and then retie it with a bowline? Where is the hostility coming from? First of all I am not sure why you believe that if I insist on not knotting my cordelette then "nothing anyone can say is going to do much good." I am asking about the stability and safety of a knot. If you do not have that knowledge then thanks anyways. Secondly, if you want an example, for instance I need to tie the cordelete around a large rock formation. If the cordelete is in a loop it would take more than double the amount of rope to tie it around as opposed to it being open. I know I might be the beginner but i dont need you arrogant "benefit of the doubt".
(This post was edited by jberk on Jun 9, 2013, 8:06 PM)
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padlinfool
Jun 9, 2013, 8:22 PM
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acorneau wrote: padlinfool wrote: swaghole wrote: Instead of climbing wiith a cordalette that is tied in a loop, you could try building your anchors with a cordalette that is not looped but instead has figure 8s tied at each end. The above method will not equalize the pieces well as most of the load will be transferred to the piece with the double strand. The single strands will stretch more because there is less material on those legs. You're missing the concept of clipping the two ends to the same piece and then continuing the regular cordelette system as usual. That yields the same result as a looped cord but without actually having the two ends tied together. Yes, that concept is better, but it is not stated in swaghole's post. I still believe the double knotted leg will stretch more and contribute less. I don't think "equalization is myth" (per bearbreeder), just an unattainable goal, but a goal all the same. Otherwise, we would just be chaining be stuff together, redundant yes, but not the best system. The attempted sharing of the load among the pieces is a major concept of a bomber anchor. I still prefer the open ended cordelette setup with its adjustable length, single masterpoint knot and unknotted, doubled legs ..where possible..YMMV
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jmeizis
Jun 9, 2013, 11:23 PM
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I tie my cordalettes exclusively with single EDK's in 6 and 7 mil nylon cord. I use my cordalette this way during the 200 or some odd days I spend climbing outside. In the several years I've been using this configuration I have not had a problem. That does not mean it is without limitations. I find it helpful to untie it on alpine climbs where I may be threading around boulders or rock pinches. I find I untie it less often for setting up topropes or any single pitch stuff. There are plenty of other knots for joining ropes, depending on their application and your needs some may be better. Make sure it's dressed and you have decently long tails. Assuming you build bomber anchors then the capsizing of the knot is irrelevant because it is isolated from the rest of the anchor legs by the masterpoint knot. If you are not isolating the knot in your anchor you may consider a different knot.
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moose_droppings
Jun 10, 2013, 12:34 AM
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Have you tried the figure 8 bend. Comes apart fairly easily even after a good force has been applied.
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jberk
Jun 10, 2013, 12:54 AM
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moose_droppings wrote: Have you tried the figure 8 bend. Comes apart fairly easily even after a good force has been applied. Are you referring to the Flemish figure eight?
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jberk
Jun 10, 2013, 12:56 AM
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jmeizis wrote: I tie my cordalettes exclusively with single EDK's in 6 and 7 mil nylon cord. I use my cordalette this way during the 200 or some odd days I spend climbing outside. In the several years I've been using this configuration I have not had a problem. That does not mean it is without limitations. I find it helpful to untie it on alpine climbs where I may be threading around boulders or rock pinches. I find I untie it less often for setting up topropes or any single pitch stuff. There are plenty of other knots for joining ropes, depending on their application and your needs some may be better. Make sure it's dressed and you have decently long tails. Assuming you build bomber anchors then the capsizing of the knot is irrelevant because it is isolated from the rest of the anchor legs by the masterpoint knot. If you are not isolating the knot in your anchor you may consider a different knot. Thanks so much. How much tail do you recommend with 6mm cordelette with an EDK backed up with another EDK? Is 6inch enough? My cordelette is a little stiff, should i leave more? Thanks.
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jberk
Jun 10, 2013, 1:46 AM
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rgold wrote: jberk wrote: Where is the hostility coming from?...i dont need you arrogant "benefit of the doubt". Ok, sorry about that, carry on with what you want to do. You've had several answers, and the best is to not have any knots in the cordelette at all. Here's a video that explains how to do it and gives the advantages of the approach. http://www.youtube.com/watch?v=qF4A85CPr8c Thanks. I do like this method it really does seem to eliminate the knot as a failure point. My only concern is that I haven't really found it it any materials aside from youtube. Have you used it? Is this method commonly used?
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shockabuku
Jun 10, 2013, 2:43 AM
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Flemish bend may work better.
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ncrockclimber
Jun 10, 2013, 2:53 AM
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jberk wrote: Where is the hostility coming from? First of all I am not sure why you believe that if I insist on not knotting my cordelette then "nothing anyone can say is going to do much good." I am asking about the stability and safety of a knot. If you do not have that knowledge then thanks anyways. Secondly, if you want an example, for instance I need to tie the cordelete around a large rock formation. If the cordelete is in a loop it would take more than double the amount of rope to tie it around as opposed to it being open. I know I might be the beginner but i dont need you arrogant "benefit of the doubt". jberk, You just acted like an ass to one of the most experienced and knowledgable folks who still posts on this site. If you continue to climb and increase your knowledge base, you will someday understand how stupid you look right now. From your post above and others in this thread it is obvious that you are inexperienced and not open to feedback. In the future when posting you should just tell folks what you are going to do, then ask only for responses that applaud your plans. It will save folks from wasting their time responding with ways in which you can improve your technique and increase your safety. Cary on, and good luck.
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acorneau
Jun 10, 2013, 2:53 AM
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jberk wrote: moose_droppings wrote: Have you tried the figure 8 bend. Comes apart fairly easily even after a good force has been applied. Are you referring to the Flemish figure eight? Yes, the Figure-8 bend and the Flemish bend are the same thing: http://www.animatedknots.com/....php?Categ=typebends
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billl7
Jun 10, 2013, 3:05 AM
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rgold wrote: The method isn't commonly used as far as I know, and I don't know of it making it into any books yet. About 9 years ago, a local guide showed it to me during a day of training. Haven't seen it in use since though maybe it is more common amongst SAR folks? I can imagine them having quite a bit more occasion to use an open stretch of cord. The video is helpful although the guide did not suggest closing the loop at the time. I wonder if the reason for tying the ends together relates to anchoring using the shelf (something I haven't found really necessary anyways and very rarely do). Likewise, I haven't seen anyone actually using the technique (i.e., untied ends). But seems okay. I find myself frequently tying knots without backing up the tails - situation dependent. Bill L
(This post was edited by billl7 on Jun 10, 2013, 3:06 AM)
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jberk
Jun 10, 2013, 3:09 AM
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ncrockclimber wrote: jberk wrote: Where is the hostility coming from? First of all I am not sure why you believe that if I insist on not knotting my cordelette then "nothing anyone can say is going to do much good." I am asking about the stability and safety of a knot. If you do not have that knowledge then thanks anyways. Secondly, if you want an example, for instance I need to tie the cordelete around a large rock formation. If the cordelete is in a loop it would take more than double the amount of rope to tie it around as opposed to it being open. I know I might be the beginner but i dont need you arrogant "benefit of the doubt". jberk, You just acted like an ass to one of the most experienced and knowledgable folks who still posts on this site. If you continue to climb and increase your knowledge base, you will someday understand how stupid you look right now. From your post above and others in this thread it is obvious that you are inexperienced and not open to feedback. In the future when posting you should just tell folks what you are going to do, then ask only for responses that applaud your plans. It will save folks from wasting their time responding with ways in which you can improve your technique and increase your safety. Cary on, and good luck. First of all I did post in the beginners forum so I do recognize that my information base is lacking. Secondly, I am not sure if you are simply slow but the entire purpose of my post was inquiring about the safety of knot. Or if someone had another knot suggestion that would accomplish the same effect. I did not once ask for someone to "applaud" my technique, rather I was attempting to confirm its safety. I am not opposed to new information or advice from experts but I do have a specific need. Feedback telling me that my needs are non-existent is a useless post. I did not ask you to spend time addressing my questions and needs so dont attempt to grandstand with regards to your time.
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jberk
Jun 10, 2013, 3:10 AM
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rgold wrote: jberk wrote: My only concern is that I haven't really found it it any materials aside from youtube. Have you used it? Is this method commonly used? It's what I do with my cordelette, but as you may have surmised from my "arrogant" remarks, I almost never even carry a cordelette. The method isn't commonly used as far as I know, and I don't know of it making it into any books yet. But it makes more sense, doesn't it? Abosuletly. I think that this might be the perfect solution, thanks so much!
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ncrockclimber
Jun 10, 2013, 3:24 AM
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Wow. You are inexperienced, arrogant and a dick. I'm done.
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rgold
Jun 10, 2013, 3:36 AM
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Yes Bill, the idea has been around for a long time. I think it isn't popular because most people who use cordelettes don't untie them. (We have Jim as a counterexample to that claim, however.) Forgetting about untying the cordelette, the video makes it evident that there are other advantages to the no-knot method, e.g. adjustability. I do think the part about tying the ends together in order to "close the system" is silly. There is nothing "open" about the system without that extra little knot. On the other hand, it doesn't hurt anything to tie it either. Personally, I don't do it. Without, I hope, raising again the issue about who is, in fact, arrogant, I at least would not be particularly happy with a belay anchor made of a single loop of 7mm or less cord around a rock feature. The issue is the susceptibility of small-diameter cordage to cutting or abrading when in contact with multiple facets and features of a complex rock surface and subjected to either shock loads or cyclical loading. I don't know of any data on this but have seen some very sobering examples.
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jt512
Jun 10, 2013, 5:35 AM
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jmeizis wrote: I tie my cordalettes exclusively with single EDK's in 6 and 7 mil nylon cord. I use my cordalette this way during the 200 or some odd days I spend climbing outside. In the several years I've been using this configuration I have not had a problem. Well, anyone who ever has had a problem doing that is no longer here to talk about it. Likewise, the first time you have such a problem will also be the last. The EDK is basically a crappy knot whose weaknesses happen to not matter very much for joining rappel ropes, because rappel ropes don't need to withstand large loads. Additionally, the EDK has a unique low profile that makes it less likely to get stuck while pulling rappel ropes. But, if subjected to large loads, the EDK rolls repeatedly, and unless tied with long tails (recommended 18 inches long in climbing rope), the knot can roll off the ends of the rope, in which case, RIP. These characteristics make the EDK a good knot for joining rappel ropes, but not much else, save clipping your approach shoes to your harness. A multipitch belay anchor should be able to withstand a factor-2 fall with a safety margin to spare. This is not the place for a knot whose behavior under high loads is to repeatedly roll. The double fisherman is the tried-and-true knot for tying a cord into a loop that must be able to withstand a high load, because it tightens under loading, an evidently desirable characteristic.
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billl7
Jun 10, 2013, 12:15 PM
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jt512 wrote: The EDK is basically a crappy knot whose weaknesses happen to not matter very much for joining rappel ropes, because rappel ropes don't need to withstand large loads. Additionally, the EDK has a unique low profile that makes it less likely to get stuck while pulling rappel ropes. But, if subjected to large loads, the EDK rolls repeatedly, and unless tied with long tails (recommended 18 inches long in climbing rope), the knot can roll off the ends of the rope, in which case, RIP. These characteristics make the EDK a good knot for joining rappel ropes, but not much else, save clipping your approach shoes to your harness. A multipitch belay anchor should be able to withstand a factor-2 fall with a safety margin to spare. This is not the place for a knot whose behavior under high loads is to repeatedly roll. The double fisherman is the tried-and-true knot for tying a cord into a loop that must be able to withstand a high load, because it tightens under loading, an evidently desirable characteristic. Excellent summary about the EDK.
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jmeizis
Jun 10, 2013, 12:30 PM
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Yeah, six inches is enough. If you're concerned then adding a backup isn't a bad idea. As has been pointed out it will roll at relatively low loads. So do clove hitches. Know the limits of your system. If the knot rolling would cause catastrophic failure then use a different knot.
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billl7
Jun 10, 2013, 12:46 PM
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jmeizis wrote: I tie my cordalettes exclusively with single EDK's in 6 and 7 mil nylon cord .... As has been pointed out it will roll at relatively low loads. So do clove hitches. Know the limits of your system. If the knot rolling would cause catastrophic failure then use a different knot. Much of our rigging systems for climbing only have the strength / redundancy / safety factor that we build into them. Often, individual pieces / parts area not all that far from failure in a hard lead fall. A hard "lead fall" includes someone being at the end of their anchor tether, above the anchor, slipping, and falling onto the anchor. Beginners should be wary of handicapping one leg of the rigging by incorporating a poor knot. Bill L
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jberk
Jun 10, 2013, 3:22 PM
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Thanks everyone for all of your amazing feedback and help. I am going to only use the EDK backed up with an overhand only in low load/rappel situations due to its susceptibility to rolling and stick with this method http://www.youtube.com/watch?v=qF4A85CPr8c as suggested. Thank once again !!
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cervicornis
Jun 10, 2013, 4:10 PM
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jmeizis wrote: Yeah, six inches is enough. If you're concerned then adding a backup isn't a bad idea. As has been pointed out it will roll at relatively low loads. So do clove hitches. Know the limits of your system. If the knot rolling would cause catastrophic failure then use a different knot. By definition, clove hitches do not roll, and it is probably a myth that they slip under high loads. I recently tested this myself using a retired piece of rope, a tree, and my truck.
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rgold
Jun 10, 2013, 4:58 PM
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Right---clove hitches don't roll. And whether they slip or not is a matter of some contention. In any case, the mention of clove hitches is irrelevant in the current context because, when used to anchor a belayer, there is no end to pull through a slipping hitch and cause a catastrophe. The hitch just slips, if indeed that does happen, and would absorb fall energy, so such a result is not only not a problem, it might actually be a potential benefit. The tests I've seen suggest that clove hitches do not slip in dynamic ropes but might slip a little in static ropes. Jim Ewing tested a clove hitch used as a tie-in in a UIAA drop test and it failed completely. Fox guides publicized some tests years ago that suggested significant slippage, but no one has been able to replicate those results and the data has since been lost or suppressed, leading to the conclusion that those tests were seriously flawed. Given the inferiority of the EDK as a general joining knot and the fact that the no-knot cordelette rigging method is superior anyway, there doesn't seem to be any reason to use an EDK as a cordelette knot.
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Winemaker
Jun 10, 2013, 6:03 PM
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http://user.xmission.com/~tmoyer/testing/EDK.html Here's a very good analysis with pull data for the EDK versus other knots. There are also some thoughtful recommendations.
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chris
Jun 20, 2013, 4:05 PM
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jmeizis wrote: I tie my cordalettes exclusively with single EDK's in 6 and 7 mil nylon cord. I use my cordalette this way during the 200 or some odd days I spend climbing outside. In the several years I've been using this configuration I have not had a problem. That does not mean it is without limitations. I find it helpful to untie it on alpine climbs where I may be threading around boulders or rock pinches. I find I untie it less often for setting up topropes or any single pitch stuff. There are plenty of other knots for joining ropes, depending on their application and your needs some may be better. Make sure it's dressed and you have decently long tails. Assuming you build bomber anchors then the capsizing of the knot is irrelevant because it is isolated from the rest of the anchor legs by the masterpoint knot. If you are not isolating the knot in your anchor you may consider a different knot. I agree with jmeizis - I've been using an doubled overhand knot to join my cordellette for 13 years. Because I'm paranoid about Jay's scenario (the factor 2 fall on the anchor, causing the overhand to roll), I back it up with a second overhand, and three inches of tail (about the width of my hand). I'll respectfully disagree with Jay and the other naysayers. This is a common and accepted standard.
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shockabuku
Jun 22, 2013, 7:39 PM
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chris wrote: I agree with jmeizis - I've been using an doubled overhand knot to join my cordellette for 13 years. Because I'm paranoid about Jay's scenario (the factor 2 fall on the anchor, causing the overhand to roll), I back it up with a second overhand, and three inches of tail (about the width of my hand). I'll respectfully disagree with Jay and the other naysayers. This is a common and accepted standard. You make this assertion with no evidence to support it and, perhaps, most of the evidence given so far contradicts what you state. It does not appear to be common in my experience. Where do you observe it being commonly used? What body endorses it as an accepted standard?
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chris
Jun 22, 2013, 9:49 PM
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Good point. I'm not sure how I would provide evidence - I'm not aware of any surveying done on this question. Every test I've seen published about the strengths of the double overhand have shown that its plenty strong enough for anchor use, especially when you consider its only attached to one leg of a multi-part anchor. So my anecdotal evidence: Amongst my friends here in the Pacific Northwest, I can't think of anyone who doesn't use an double overhand to tie their cordellette. I first learned about using it in 2000, became comfortable with using it within a year, and quickly saw it being adopted where I've been climbing over the past 10 years. The AMGA teaches in its courses that an doubled overhand is an acceptable knot for a cordellette. In fact, that's how I learned about it in 2001. And I've seen it taught and used in every course and exam I've participated in since then (6 courses and 3 exams in total). I just spent a month in the Alps, and I recall seeing several IFMGA Mountain Guides using it there as well. This is very much a non-issue in the guiding community. Both knots are acceptable.
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bearbreeder
Jun 23, 2013, 2:10 AM
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chris wrote: Good point. I'm not sure how I would provide evidence - I'm not aware of any surveying done on this question. Every test I've seen published about the strengths of the double overhand have shown that its plenty strong enough for anchor use, especially when you consider its only attached to one leg of a multi-part anchor. So my anecdotal evidence: Amongst my friends here in the Pacific Northwest, I can't think of anyone who doesn't use an double overhand to tie their cordellette. I first learned about using it in 2000, became comfortable with using it within a year, and quickly saw it being adopted where I've been climbing over the past 10 years. The AMGA teaches in its courses that an doubled overhand is an acceptable knot for a cordellette. In fact, that's how I learned about it in 2001. And I've seen it taught and used in every course and exam I've participated in since then (6 courses and 3 exams in total). I just spent a month in the Alps, and I recall seeing several IFMGA Mountain Guides using it there as well. This is very much a non-issue in the guiding community. Both knots are acceptable. RCer "experts" know way more than any stinking AMGAers or IFMGAers
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bearbreeder
Jun 23, 2013, 7:50 AM
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jt512 wrote: bearbreeder wrote: RCer "experts" know way more than any stinking AMGAers or IFMGAers Heill mein AMGA Führer! Quoted for posterity ya RC "expert"
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shockabuku
Jun 23, 2013, 9:26 AM
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Thanks for a thoughtful reply.
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rgold
Jun 23, 2013, 5:39 PM
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Bearbreeder loves to contrast the experts with the "experts," but one of the things folks sometimes forget is that there isn't a single thing called "expertise," there are actually different types of expertise. Guides are (or should be) expert at all aspects of guiding. Since it is surely never anticipated that a guide will factor-two onto the belay, considerations relevant to that scenario do not need to be part of a guides's expertise. A cordelette tied with a flat overhand is undoubtedly adequate for all guiding applications, but non-guided parties who may be pushing themselves on climbs with marginal protection can be pardoned for not treating guiding knowledge as applicable, without question, to their situation. It is true that there isn't much evidence out there, so we have to make do with what there is. The only relevant tests I know about are in http://efclimbers.net/...nd-cord-strength.pdf. What Blue Water found is that a flat overhand (EDK) in a loop of 7mm cord had a breaking strength of nearly 13 kN, with breakage at the knot. Loops of 7mm cord tied with a double fisherman's broke at about 18 kN, with breakage at the pulling pin (i.e. at the carabiner). So the flat overhand appears to be the weak point in a loop, whereas the double fisherman's is not. The 13 kN breaking strength is more than adequate for use in one arm of a cordelette. But it is arguably marginal for a worst-case scenario if the cordelette is used as a single loop. If the leader were to take a standard UIAA fall with the lead rope clipped to the anchor, loads around 13 kN are possible with a static belay. Some climbers and most engineers would consider an essentially zero margin of safety to be problematic in this situation. My take would be that the flat overhand is fine as long as the cordelette isn't used as a single loop that could be the sole protection point for a leader fall, which presumably includes all guiding situations. But personally, I can't see the logic of using an inferior knot, designed for other purposes that do not include high loads. The only argument I can think of is the desire to untie the cordelette regularly, but if that is genuinely a consideration, then the method I posted the video for earlier seems to be a more intelligent solution.
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chris
Jun 24, 2013, 1:05 AM
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Interesting - the paper you cite, rgold, was written by a AMGA certified guide and published in an AMGA quarterly newsletter. Just to be clear, I don't advocate that the flat overhand was applicable in all conditions. I would also caution about using a single strand-ed cordellette for any anchor. The breaking strength of 6mm cord is 2000 lbs, or 9 kn. 7mm breaking strength is 2800 lbs, or 13 kn. While these are adequate for static loads like rappelling, no one would consider that adequate for a shock load. My imagination of the OP scenario looked like this: I want to use this 20' tall tree as my anchor, so I untie my cordellette, do two wraps around the tree, retie the cord, and then tie a master point. Voila. Another study on the subject is at Black Diamond. http://blackdiamondequipment.com/...l?q=qc%20lab%20knots
(This post was edited by chris on Jun 24, 2013, 1:33 AM)
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jt512
Jun 24, 2013, 1:22 AM
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rgold wrote: It is true that there isn't much evidence out there, so we have to make do with what there is. The only relevant tests I know about are in http://efclimbers.net/...nd-cord-strength.pdf. What Blue Water found is that a flat overhand (EDK) in a loop of 7mm cord had a breaking strength of nearly 13 kN, with breakage at the knot. Note that the reported 13-kN strength was the average breaking strength. This figure is useless without also knowing the standard deviation, which was not reported. After all, about half of the samples would break below the average strength. The question is, how much? As a side note, is it odd that he found that the flat-8 was stronger than the flat overhand for connecting ropes? Didn't the famous Chris Harmston tests find not only the opposite, but that the flat-8 was flat-out dangerous?
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rgold
Jun 24, 2013, 3:34 AM
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I don't recall anything about breaking strength, but the flat eight did turn out to be very dangerous and resulted in some fatalities, one of them in Zion. Whatever the previous testing protocols were, they didn't include testing the behavior of the knots under relatively heavy cyclic loading, conditions that are exactly what happens when rappelling. The Zion accident involved a climber rappelling with a haul bag, I think, which meant the weight involved was bigger than just an average body weight.
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rgold
Jun 24, 2013, 3:47 AM
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chris wrote: The breaking strength of 6mm cord is 2000 lbs, or 9 kn. 7mm breaking strength is 2800 lbs, or 13 kn. While these are adequate for static loads like rappelling, no one would consider that adequate for a shock load. I mentioned this, along with the concern about abrasion of a thin cord on rock features, as reasons to be wary of a single loop used as an anchor. That observation didn't seem to be of interest.
chris wrote: My imagination of the OP scenario looked like this: I want to use this 20' tall tree as my anchor, so I untie my cordellette, do two wraps around the tree, retie the cord, and then tie a master point. Voila. Maybe, but if you were going to wrap the cordelette twice around the tree, there would be no reason to untie it, since you could just wrap the tied loop around once. It seems to me (as a very occasional cordelette user) that there is no reason to untie a cordelette unless you are going to use it as a single loop, one that can't simply be dropped over the feature being employed.
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knudenoggin
Jul 3, 2013, 5:21 AM
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rgold wrote: chris wrote: The breaking strength of 6mm cord is 2000 lbs, or 9 kn. 7mm breaking strength is 2800 lbs, or 13 kn. While these are adequate for static loads like rappelling, no one would consider that adequate for a shock load. But if you're closing this cord in a loop/circle/sling, you need to double the strength (roughly) --5,600#, then.
In reply to: chris wrote: My imagination of the OP scenario looked like this: I want to use this 20' tall tree as my anchor, so I untie my cordellette, do two wraps around the tree, retie the cord, and then tie a master point. Voila. Maybe, but if you were going to wrap the cordelette twice around the tree, there would be no reason to untie it, since you could just wrap the tied loop around once. Or make a girth hitch (for reach), putting the end-2-end knot perhaps even AT the collar of this hitch, or else somewhere around the tree.
In reply to: It seems to me (as a very occasional cordelette user) that there is no reason to untie a cordelette ... But what is the reason TO TIE it? The canonical form of the (structure) "cordelette" is a 3-legged, 3-armed being with a knotted waist; the legs are longer and must be able to withstand full load, as they are uniquely anchored; whereas the arms are jointly clipped as the power point. If a bight (arm/leg) of this material can withstand full load, why must one clip three of them as the powerpoint eye? --two should do, and maybe be easier on the clipped 'biner, less likely to load off-axis; that leaves one arm unneeded here, unclipped : : : and might as well ... untied --it would be the ends of one cord. Of course, you can tie them together, and an "EDK" makes best sense, as one can tie that snug to the powerpoint knot, where it might serve qua stopper for any slippage through the powerpoint knot to these cord tails --each tail goes to a different "leg", note. (And I think that the aforementioned video does this, but I've not seen it.) Maybe I should've Replied-with-Quote of the prior comment, WAY above, who nicely credited me for this observation/recommendation --there should be more posts like that, eh?! (In my mind there are.) Now, some remarks about the knotty things uttered above, which bear repeating in hopes that repetition breeds comprehension. "... is stronger ..." :: for the main, this consideration is both largely irrelevant in the knotting climbers do (things are not breaking, so one might regard them as equally strong by this practical pass/fail test), and often not well assessed : e.g., HMPE (Spectra/Dyneema) cord proves stronger on the test device in slow-pull testing but effectively weaker in dynamic loading for its lack of "shock absorption". The same might be true of the above-advanced knots competition between the EDK and others, should that rumored "rolling" have the effect of absorbing force while the competitor knot is tightening!? --YMMV. Moyer's testing in large showed not-so-much rolling, but ... ... there is much more variability to the offset water knot (it is *offset* from the axis of tension, it is NOT "flat") than is generally recognized. One can orient the knot body in a range of about 180deg of rotation (looking *down* at the knot, say, pulled tight over a desk top, and in so doing change one side's entry into it from a backward looping to a forward arcing; then there is the tightening, and ... . It's surprising to see single tests cited as proving anything, given how many factors might be at play AND the test having no hint about how these factors were valued/set in the test, even. As for strengths of the offset water knot vs. offset fig.8, one FYI data point (note caution above!) from the CMC Rope Rescue Manual found the fig.8 to be about as strong as the butterfly (which was to be preferred precisely on this sort of *through*/end-2-end loading (eye unloaded), and stronger that the end-2-end-loaded Directional-fig.8. 69% - 65% - 59% My, ... the irony!. --in some (large) rope (low-elongation), in slow-pull loading, in some (unknown) orientation ... (and 5 tests per knot) *kN*
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knudenoggin
Jul 3, 2013, 5:30 AM
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padlinfool wrote: swaghole wrote: Instead of climbing wiith a cordalette that is tied in a loop, you could try building your anchors with a cordalette that is not looped but instead has figure 8s tied at each end. The above method will not equalize the pieces well as most of the load will be transferred to the piece with the double strand. The single strands will stretch more because there is less material on those legs. You could just NOT tie the cordelette into a loop.... by pulling the loose ends through the one main knot. Pretty easy to do. -Grab both ends together (creating an imaginary loop). -Clip your pieces and pull down the loops to your loose ends. You can adjust the length of the loops by pulling slack on loose ends(great feature). -Tie your knot (8 or overhand) with the loops and loose ends. -Tighten and dress....even the loose ends You will end up with double strands to all pieces (with no knots), a big knot, 2 loop masterpoint (for a 3 piece anchor) plus the loose ends exiting from the bottom of the knot. Credit to knudenoggin for this concept. Best post ever! (besides my own, natch ) Though, seriously, if one is using HMPE/Technora-cored cord, DO tie off the tails, snug to the powerpoint knot, with an offset water knot (EDK) --to guard against slippage through the powerpoint knot, which in being so bulky multi-stranded will have less "nip"/grip on individual strands, and the slippery, low(no)-stretch cores have been seen to pull free of overloaded-&-broken sheaths. *kN*
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sittingduck
Jul 3, 2013, 10:39 PM
Post #66 of 72
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Registered: Aug 19, 2003
Posts: 338
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knudenoggin wrote: Best post ever! (besides my own, natch ) Though, seriously, if one is using HMPE/Technora-cored cord, DO tie off the tails, snug to the powerpoint knot, with an offset water knot (EDK) --to guard against slippage through the powerpoint knot, which in being so bulky multi-stranded will have less "nip"/grip on individual strands, and the slippery, low(no)-stretch cores have been seen to pull free of overloaded-&-broken sheaths. *kN* Have tested this method and often he loose ends becomes so short that it is hard to tie an EDK without taking of the mittens. Therefore I keep the cordelette tied in a loop.
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knudenoggin
Jul 4, 2013, 4:58 PM
Post #67 of 72
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Registered: May 6, 2004
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sittingduck wrote: knudenoggin wrote: Best post ever! (besides my own, natch ) Though, seriously, if one is using HMPE/Technora-cored cord, DO tie off the tails, snug to the powerpoint knot, with an offset water knot (EDK) --to guard against slippage through the powerpoint knot, which in being so bulky multi-stranded will have less "nip"/grip on individual strands, and the slippery, low(no)-stretch cores have been seen to pull free of overloaded-&-broken sheaths. *kN* Have tested this method and often he loose ends becomes so short that it is hard to tie an EDK without taking of the mittens. Therefore I keep the cordelette tied in a loop. Fine, but : (1) with non-hi-mod cord, you shouldn't need them tied; (2) or have the knot pre-tied, but arrange for it to be positioned *through* the powerpoint knot so that you have the same result --end-2-end knot is unloaded. AND, given the usual advice to "leave long tails" for the offset water knot (EDK), well, that makes one pause about how extensive one's cordelette loop is in first place, no?! (One does NOT need long tails for this knot positioned as suggested above, and esp. if tied snug to the powerpoint knot, where rolling isn't a real possibility. Similarly, the grapevine bend consumes a fair amount of rope, too.) I.e., encountering the tails-are-too-short-to-tie situation implies that you have made a cordelette structure that is longer than would've been possible to make if it had some pre-tied knots-that-consume-much-cord (EDK & long tails, grapevine) --at least the difference musn't be great between these). A pre-tied EDK w/non-long tails should work pretty well, with then the need being to simply snug this knot up both in its own setting, and putting it near the powerpoint --the overhand already made, and only the tightening left to be done, to finish : mitten doable?! *kN*
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ninepointeight
Jul 4, 2013, 6:05 PM
Post #68 of 72
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Registered: May 14, 2012
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This doesn't add up. You said the cord is rated to 19KN, but you also said it was 6mm and nylon. There is no nylon cord of a diameter suitable for a cordlette rated anywhere close to 19KN single strand. You'd be talking about 9mm for that kind of rating.
(This post was edited by ninepointeight on Jul 4, 2013, 6:11 PM)
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jberk
Jul 4, 2013, 7:03 PM
Post #69 of 72
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Registered: Jun 5, 2013
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ninepointeight wrote: This doesn't add up. You said the cord is rated to 19KN, but you also said it was 6mm and nylon. There is no nylon cord of a diameter suitable for a cordlette rated anywhere close to 19KN single strand. You'd be talking about 9mm for that kind of rating. Hey thanks, I already got my answer but to clarify this is what i have http://www.backcountry.com/...rcord-cordelette-6mm and it is 6mm and rated at 4800lbs so I made a mistake thats greater than 18 i believe its actually 21kn. Its been working out so far but a little stiff so I would make sure you got sizable tails.
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ninepointeight
Jul 4, 2013, 7:19 PM
Post #70 of 72
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Gotcha. Powercord is a blend. Not just nylon.
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sittingduck
Jul 4, 2013, 9:34 PM
Post #71 of 72
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Registered: Aug 19, 2003
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knudenoggin wrote: sittingduck wrote: knudenoggin wrote: Best post ever! (besides my own, natch ) Though, seriously, if one is using HMPE/Technora-cored cord, DO tie off the tails, snug to the powerpoint knot, with an offset water knot (EDK) --to guard against slippage through the powerpoint knot, which in being so bulky multi-stranded will have less "nip"/grip on individual strands, and the slippery, low(no)-stretch cores have been seen to pull free of overloaded-&-broken sheaths. *kN* Have tested this method and often he loose ends becomes so short that it is hard to tie an EDK without taking of the mittens. Therefore I keep the cordelette tied in a loop. Fine, but : (1) with non-hi-mod cord, you shouldn't need them tied; (2) or have the knot pre-tied, but arrange for it to be positioned *through* the powerpoint knot so that you have the same result --end-2-end knot is unloaded. AND, given the usual advice to "leave long tails" for the offset water knot (EDK), well, that makes one pause about how extensive one's cordelette loop is in first place, no?! (One does NOT need long tails for this knot positioned as suggested above, and esp. if tied snug to the powerpoint knot, where rolling isn't a real possibility. Similarly, the grapevine bend consumes a fair amount of rope, too.) I.e., encountering the tails-are-too-short-to-tie situation implies that you have made a cordelette structure that is longer than would've been possible to make if it had some pre-tied knots-that-consume-much-cord (EDK & long tails, grapevine) --at least the difference musn't be great between these). It should be fairly easy to learn how much rope to leave for the EDK if one chose to use this method.
knudenoggin wrote: A pre-tied EDK w/non-long tails should work pretty well, with then the need being to simply snug this knot up both in its own setting, and putting it near the powerpoint --the overhand already made, and only the tightening left to be done, to finish : mitten doable?! *kN* That is doable with mittens. Do you think the snug-to-the-powerpoint EDK could make untying the powerpoint more difficult? (this is one of the exact reasons I try to keep the pre-tied fisherman away from the powerpoint)
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knudenoggin
Jul 5, 2013, 5:28 PM
Post #72 of 72
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Registered: May 6, 2004
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sittingduck wrote: Do you think the snug-to-the-powerpoint EDK could make untying the powerpoint more difficult? (this is one of the exact reasons I try to keep the pre-tied fisherman away from the powerpoint) Maybe it's a "YMMV" case, but I'd expect that one could yet do the sorts of bending/prying/pulling on the powerpoint knot to loosen it. In the usual case, the strands that here are knotted would be loaded (if no failed anchors, all six are loaded, both sides of the knot); if one bight on the attach-to side is left unloaded (maybe even untied), then you have four strands delivering somewhat greater tension to the knot opposite the six anchoring ones, which will increase the four's tightness, but ... . *kN*
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