I have 20+ years of guiding experience, was an AMGA certified rock instructor, and served five years as the AMGA executive Director, and I want to commend you on your excellent analysis and presentation. This video will save lives.
Great information. I didn't think the stacked overhand would roll and I didn't realize the double overhand was 25% stronger than the stacked. Very helpful!
A friend from Rigging for Rescue in Ouray Colorado introduced the double overhand to me several years ago. They also did some pull tests that confirmed it doesn't roll, but I never saw it in writing. Saved Grant's PDF report when I first saw it. Good stuff. Generous of you to provide ropes for the tests, Pete.
Great presentation as always, Rich! Would love to see pull tests compare your half-double-fisherman's dressed double OH, and the two-half-hitch (hope that's a correct description) dressed double OH that's also out there, a.k.a. Gibb's knot. Possibly two different knots with the same name- LOL, like that never happens! But however you tie it, you can dress the wraps either way. I suspect the two-half hitch dressed one (Gibb's) may be less - but still adequately - strong but easier to untie after loading.
Rich, very informative. Interesting and practical. Thank you. You recommended using a rethreaded figure 8 bend to tie two ropes together (say, when you rappel with the load on the knotted side) because it sustains loads along its' major axis and that it retains 60-70% of the strength of the rope. Makes sense. The table near the end of the video says a double overhead knot breaks at 55% of the rope's strength. With a 5,000 lb canyoneering rope, the figure 8 breaks at 3,000-3,500 whereas the double EDK at 2,750. Even though the figure 8 is stronger, is the difference significant in the field (i.e. canyoneering) and when considering that the EDK has less chance of getting stuck when pulled (retrieved after rappel)? Thank you very much.
I'm with you on the double overhand. Never had it roll on me even once. and hey, if your worried you can always tie an edk as a back up. Though I'm amazed by how few people use it. All the time when I tie that people look at it and ask, "what the hell is that?!" lol
I always use the double 8 knot to tie two ropes for abseiling down. Only once in 25 years of climbing I got a knot caught, but it was in a rock wall heavely eroded by exokarst, so it got caught inside a big lapiaz (in fact any knot would have). But what I see with horror in your video is the way you pass the belay rope (I don't know how to say "cordelette" in english) throught the bolts!!! Never, never, never pass a rope directly through a bolt, use always a metallic ring or carabiner. Ropes and bolts must never be together, cos the bolt can cut a rope like a knife. That's why in Europe all the belays in sport climbing and all the abseiling belays in multipitch routes are equipped with rings. And that's why we always have 2-3 maillon rapide in our harness, so we can abandon them in non-equiped belays (it's cheaper than a carabiner). Of course we use UIAA certified maillon rapide, not ironmongery ones.
that's not cordelette, 1 inch tubular webbing which has 4000 pounds of strength on one strand (equivalent to about 14-15 people's weight!) As someone, who has done canyoning in both USA and Europe with canyon guides, there is nothing wrong in this video. Europe and USA canyon community use different techniques when it comes to rigging pitches. That does not mean, one is right the other is wrong. Next time, you are going to reflect your wisdom on people make sure you know the shit you are talking about. You sound like a climber, so it is possible you donät know canyoning techniques or experienced guys in the field. But, even one of the experienced French canyon guides who works for the French government to train canyon guides knows Rich, and trusts his skills. Your last couple of statements were even more laughable regarding how to choose maillon or the price of rapides being cheaper than a carabiner. Really? We didn't know that thanks for chipping in.
Thanks for the great videos. In another video you mentioned using a butterfly knot to isolate a core shot in a rope. I also found some research showing that butterfly knots are some of the best in terms of strength reduction. My question is, has using a pseudo butterfly to connect two ropes been used in this manner? As if the two tails meeting represented a weak point in a damaged rope? I'd be interested in your thoughts and maybe testing if possible. Thanks.
Happy to hear you are enjoying the videos. I have stumbled across some info about re-threaded butterfly knots, but the context was getting the loop of the butterfly into a non-opening ring. Haven’t seen anything on using a butterfly as a bend to connect two ends of rope or cord.
How easy is it to untie the double flat overhang after , for example, 10 piches rappel ?? Since it is like a double fisherman, I suspect it to be hard to untie after multiple rappel
I have never had difficulty untying the double flat overhand, but I have never left it tied and weighted for 10 pitches. It looks like a double fisherman, but it is not being loaded the same way and I think that makes a difference. If you ever try it in that application I hope you will let me know how it works for you.
I'm french and I can tell you that we didn't do this we do a second knot to evict rolling and the eight knots isn't good becaus he can be stuck when you make it down. The "death knot" is difficult to stuck
Not trying to be rude, but if you are trying to prevent any rolling or slipping of any kind on the double overhand, couldn't you just tie the tails together ensuring that the two ropes could never come apart?
Rich, maybe I am missing something, but when you say the "EDK will become more of a block" 1:15 if using only one side of the rope, does that assume you are using a small enough rap ring or quicklink so the knot won't slip through (sounds like pearabiners and even Ds are out of the question)? Seems a little risky, like it might pop through with even a little unexpected dynamic loading.
Yes unless you're certain there is no chance of the rope hanging up the EDK or DEDK is the way to go. Even if the rope hangs up you can pull it back the other way , try again and you'll likely be successful eventually
It depends on the size of the ring. A knot tied in small diameter ropes blocked against a large ring vs knot tied in thick ropes blocked against a small rapide. No rules. Common sense required.
Sure, you can open it easier after retrieving, but it will be harder to retrieve because it is more likely to get caught in cracs. So just use another knot then 🤷♂️ Anyhow, joinong rooes using the "EDK" is considered save here in Austria when used ONLY for rapellig, as the force wont exceed 2kn under normal circumstances (2kn are about 200kg of pulling force)
You mentioned that the overhand knot could slip down if you used two different types of ropes and didn't thread the thicker rope through first . my thoughts are what happens if you have two ropes of the same size , is there a chance that while abseiling down the rope that one strand will have a little less tension on and cause the knot to slip away from the d-shackle and cause the same danger... i assume it would only have to slip 1cm down to be loaded wrong
like for instance the atc tube belay device has two tubes but when i belay, i normally use the right hand side just because i'm right handed which would cause the one tube to wear and would create a slight difference or the angle the ropes come out the device or two ropes of the same size but different manufactures or different age ropes or different types, dry core and uni core or even just the way that i hold the ropes, i'm not a machine and can guarantee that i'm putting the same tension on both strands
I don't think I said there would be a difference in TENSION. There would be a difference in FRICTION (of rope passing through rappel device); more on the thicker rope, less on the thinner rope. If I am rappelling on two strands of same-diameter rope and the bend connecting the two is 1cm or 10cm from the rappel ring, I would not be concerned. My weight will be split between the two strands so the bend will not be taking the full load.
Are you suggesting tying two ropes together using a water knot? The advantage of the EDK is that it tends point away from the rock and be less likely to become stuck. If getting stuck is not an issue I would much rather use a double fisherman bend or Flemish bend. Not a water knot.
Consider the primary reason we sometimes choose a flat overhand (EDK) over other, more secure bends. It is because the flat overhand is less likely to get stuck due to the way it lays on the rock. WHEN TIED CORRECTLY WITH SUFFICIENT TAILS - AND USED APPROPRIATELY, the flat overhand is secure enough. Adding stopper knots will increase the odds of getting the rope stuck, so if you feel the need to add the stoppers why not just go back to using a different bend?
The zeppelin bend is not in common use. Before using it, be sure you have checked to make sure it has been tested for your intended purpose. I would hesitate to use it unless all of my partners are trained in its use as well so they can feel confident in their system checks.
What about an alpine butterfly against the ring....with the overhand in the "loop" of the alpine. Does the different diameters of rope effect the alpine?
Thank you for your comment, Adrian. Figure 8 and fisherman "bends" make sense most of the time. The only reason to switch to a FLAT overhand or double overhand is when you are concerned your rope might bet stuck when retrieving. The flat overhand and double overhand are less likely to become stuck because their profiles tend to hold them away from cracks and lips.
@@adrianboloveschi7266 also its easier to get out an overhand knot after retrieving the rope. Doublefishermans you would need tools to remove if you really load it.
Also simplicity of tying. I've climbed for 20 years and never seen an EDK flip once on a dynamic climbing rope when I was at the rappel rings. I've also used it on static canyoneering ropes and have yet to see it flip. Typically, my understanding, as it flips, it tightens, so it shouldn't endlessly flip anyway. My first use of it was as a 2nd year ice climber in 33F temps when it was pissing rain and I was getting hypothermic. My partner, an American raised in Germany, so a European, said, let's use the EDK. I said, hell no. He respected my decision and I futzed with a double fisherman's with frozen trembling fingers. A short while later, I said, fine just don't kill me. Never used another knot to rappel after that. Most instances of EDK failure are rarely actually EDK failure. They are usually some variation of the EDK, like the flat figure 8. I'll take my chances on the EDK for another 20 years and then some.
Not sure I'd agree given these tests.... It should be strongly pointed out that the stacked EDK didn't suck in the tails i.e. it was only the first EDK that rolled until it met the second EDK (which is exactly why the second is there). In this later test, the double overhand rolled significantly. Given these results and the information around different diameter ropes, I would recommend the stacked overhand every time. overtheedgerescue.com/rope-rescue/bends-joining-ropes-update/
Grant's revised testing certainly makes a case for choosing the stacked overhand in situations where the knot will be loaded directly and not in "climber abseil" mode or when using the knot as a block. I make it quite clear in the video that these are the only two modes for which I use a flat overhand, so I am making a personal choice to continue using the double flat overhand.
Are you asking because you don't believe in having any safety margin? As long as a knot will hold your body weight you are content? A rappeller can generate significantly more force on an anchor than their static weight, via leverage, etc.
@@CanyonsCrags "A rappeller can generate significantly more force on an anchor than their static weight" sure, but what is your claim about how much and how does that relate to the chart and your advice?
I know, this is common on his videos. Pretty annoying; he needs to fix this. Some (many) of us need to listen on headphones so as not to disturb other occupants.
Please refer to page 14 of this document for attaching two different sized rope diameters together: drive.google.com/file/d/1ClUpSQ3npYk-HvjmLWuCDYFb0vZzHOVa/view
Same here I hate the overhand bend and it's sick to untie after heavy load just use a Zeppelin bent or a Carrick bend or something better than a bloody granny knot
There could be confusion between the Stacked Overhand and the Double Overhand , rightly or wrongly I've always called the Stacked Overhand the Double Overhand. It might be more descriptive to call the Double Overhand the "Inverted fishermans" but WTH to I know
