Double sheet bend for rappelling
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I was wondering if anyone sees a problem with using this knot for rappelling? |
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Just use a EDK (or a double EDK) - which is a simple overhand knot. |
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EDK |
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everything is a trade off one way or another, the double sheet bend is the best knot for attaching two lines of different diameters, and like a bowline extremely easy to untie. BUT the advantage of the EDK is that it natually turns outwards when pulling making it less likely to jam in a crack. normally even though your climbing rope diameters are differnt but they aren't THAT differnt ie say 6mm tag line and 10.2 primary at the most extreme. Sheet bend was more used by sailors for attaching a heaving line to a large mooring line think clothes line to 3 in diameter monster. |
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The sheet bend is useful for tying two ropes of different diameters together. One of the main benefits of the sheet bend or double sheet bend is that they are easy to untie. In my opinion this is not a desired trait in a knot used for repelling. Especially when doing multiple repels. |
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The first thing I think when I see that video is that I would absolutely never trust my life to that knot. But I suppose it's a cool knot and if I had two ropes and tied a double sheet bend I may think otherwise. |
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Ben Ricketts wrote:The sheet bend is useful for tying two ropes of different diameters together. One of the main benefits of the sheet bend or double sheet bend is that they are easy to untie. In my opinion this is not a desired trait in a knot used for repelling. Especially when doing multiple repels.Rappel. Sorry. |
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The EDK is the flat overhand bend on the website you mention. Do not use a figure eight like this, they capsize easily. |
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I worked on a crane and we used sheet bends all the time to attach a small guide line to the hook on the end of the load line. The reason we used the sheet bend is that you can simply shake the thing untied while you are on the ground and the hook is high above you. That's not really what I'm looking for in a rappel knot. EDK all the way! |
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MTkirk - are you sure you weren't using a blackwall hitch? |
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Good info thanks everybody |
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These guys can help you get some facts. |
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steitz wrote:MTkirk - are you sure you weren't using a blackwall hitch? The sheet bend is bomber. It's fine, it's perfectly safe. You can use virtually any bend for rappelling.Used them both, the sheet bend when there was more guide pulling involved. Yes it's more secure than the blackwall, but still with a whipping motion you can get it to untie. I guess if you had the ends long enough it would probably be pretty secure. I don't think the double turn really adds much security. It's sort of like the double bowline in that it adds more length that has to slip, but does nothing to cinch the knot tighter. |
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steitz wrote:This may be a pendantic point but a sheet bend tied around a hook isn't really a sheet bend. You can call it that and it takes the same form, but it's a different knot. A sheet bend only becomes such when tied with two lengths of line.Not pedantic at all, clarity is important in these things. You've got me fiddling with a rope, hook, and knot chart always a good thing! (do this more than I care to admit). For giggles I just joined a climbing rope with a double sheet bend exactly as in animatedknots.com/sheetbend/, took me a little less than 30 seconds of vigorous shaking to get it to untie when unloaded. No it won't come undone while loaded (when you're rapping), but I prefer my ropes to remain tied when I pull them... jus' sayin' |
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Fair enough, we've all got to respect risk and figure out what we're acceptable with. |
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MTKirk wrote: took me a little less than 30 seconds of vigorous shaking to get it to untie when unloaded. No it won't come undone while loaded (when you're rapping), but I prefer my ropes to remain tied when I pull them... jus' sayin'There's a good point. Imagine you've pulled the rope a bit and the other end is off the ground, then the knot gets stuck or jammed. You start shaking it a whipping it around and it comes untied. You're six pitches up wishing you'd have used the EDK. |
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Would never use it when rappelling. The flat overhand or flat double fisherman's are both much better. |
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BITD we used to tie equal-diameter rappel ropes together with a square knot backed up by barrel knots on each side (barrel knot=1/2 double fisherman's). When the diameters were different, it was not unusual to use a double sheet bend with the barrel backups. With those backups, you can't shake the knot loose. But this now ancient history; there's no reason nowadays not to use the EDK, which, by the way, works fine for ropes of different diameters if you tie it correctly. |
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Ryan Williams wrote: Rappel. Sorry.Don't be sorry, Ryan, other than you beat me to it. The first step to wisdom is to call things by their correct names. The next step is to spell them correctly. Moving on . . . |
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Any Beginning or Intermediate Climber:
I was wondering if it would be ok to... I had this idea... I was thinking about the way they do abc in xyz activity.. Unless you have a bunch of years and a lot of serious yardage in to it, then rock climbing really isn't an activity where you want to head out trying to innovate with the gear. Really it's just the contrary - you want to get fully steeped in the traditional uses of the gear we all conventionally use in the way we conventionally use it until it becomes more or less second nature. If you think of, or run across, something you haven't seen in common use in the gym, out at the crags, or talked about ad nauseum online - then you should probably just take a pass on it. Creativity and curiosity are great, but the old saying about the latter still rings true. |
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Fun fact - the square knot isn't actually a bend and shouldn't be relied on to reliably join two ropes. Off the top of my head I think it falls into the category of binding hitches. |