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diplodocus
Aug 18, 2003, 2:58 AM
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Is rappeling off one rope more dangerous than the regular 2 ropes? This is with reference to PPTP's method of joining 2 ropes of different diameter, where the thinner rope is used just to retrieve the thicker one
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granitegod
Aug 18, 2003, 3:30 AM
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My theory is that 2 ropes is more dangerous than 1.....no knot to come untied......shorter rappels with less chance of getting ropes stuck hundreds of feet off the ground....
But if you have hundreds of feet to rappell, rather than 80 or 90, give me double ropes, any day.
As long as you tie a good knot (I always use a double Fisherman's), you don't have to worry about a "thin" rope breaking. And I try to thread the THIN rope through the anchor, and pull the thick one.... much easier pullin'.
When climbing long routes requiring double rope rappells, having half/twin ropes really pays off, as rappelling and pulling them is much easier.
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brianthew
Aug 18, 2003, 5:36 AM
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Also, it's not so much the ropes that make rapping dangerous, it's the anchor. One rope or two, if it fails you die. Tie a good knot to join the two ropes, and heads up when you pull, no problem.
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pelliott
Aug 18, 2003, 6:19 AM
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If you are referring to the situation where the width of the knot is the only anchor, then yes, that is a dangerous setup IMO.
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the_dude
Aug 18, 2003, 6:25 AM
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I don't know about the double fishermans. My experience is after alot of raps it's hard to untie. Also it gets snagged and hung up pretty easily. Maybe I just had bad luck with it. I prefer a figure 8 on a bite with about a 16 inch tail. It has always been easy to pull and always rolls itself out of snags. I guess this explaines more of a double rope rap.
As far as rapping off of one rope(and pulling a thinner line), I don't think it's more dangerous. I've done this a few times and has seemed plenty safe, and I'm scared of rapping!
Cheers!
The Dude
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emtclimber
Aug 18, 2003, 6:26 AM
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One is safer since you don't have any knots....two makes for a longer rap.
Pro's and con's to both. I've only used singles myself....shorter raps but I don't mind.
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ajkclay
Aug 18, 2003, 1:21 PM
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I would have thought that rapping off the end of either would be dangerous, I prefer to stop rapping before I get to the end of the rope -tee hee :D
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rrrADAM
Aug 18, 2003, 1:33 PM
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Moved to General Forum. ~Adam
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diplodocus
Aug 18, 2003, 5:12 PM
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hi folks, perhaps my question wasn't clear. (only The Dude got my question right).
What I meant to ask was, is it more dangerous to rap off 1 'strand' of rope rather than 2?
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brianthew
Aug 18, 2003, 5:16 PM
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Bottom line: there are fewer things that can go wrong on one rope.
Both are safe if you know what you're doing, provided you've a good anchor.
Added: If you're rapping with a heavy load, the "strand" won't give you the same friction as doubled ropes.
Hehe, I just realized you were asking about literally, a single strand of rope. But if that's the case, then you couldn't retrieve it (without pulling one of those tricks).
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rrrADAM
Aug 18, 2003, 5:21 PM
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Answer... No.
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jeffers_mz
Aug 18, 2003, 7:40 PM
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Single strand rappelling offers some variation in technique but there are some hazards as well.
Different rope/rap device combinations offer significant differences in stopping power and the time to find that out is not near the top of a 60m drop as the rope sizzles faster and faster through your rap device.
Using a slick rope like a Bluewater 10.5, I don't trust an 8 or ATC, period. On the other hand there's a short courtesy rope at a local crag that I literally have to shove through my ATC just to make any downward progress at all.
A simple carabiner wrap is what I'm most comfortable with. Be aware that you need to know in advance how many turns to take, and that when you load it, the top loop will flip up over the top of the biner and drop you an inch or so till it tightens up.
I recently bought a Petzl Stop. Seems sweet rapping off the corner post of my coffee table but I haven't gotten to use it on a real rappel yet.
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alpnclmbr1
Aug 18, 2003, 9:07 PM
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In reply to: Maybe I just had bad luck with it. I prefer a figure 8 on a bite with about a 16 inch tail.
This is known to be a really bad knot for joining two ropes. The overhand version is much better.
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alpnclmbr1
Aug 18, 2003, 9:08 PM
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In reply to: Maybe I just had bad luck with it. I prefer a figure 8 on a bite with about a 16 inch tail.
This is known to be a really bad knot for joining two ropes. The overhand version is much better.
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thegreytradster
Aug 18, 2003, 9:31 PM
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In reply to: In reply to: Maybe I just had bad luck with it. I prefer a figure 8 on a bite with about a 16 inch tail. This is known to be a really bad knot for joining two ropes. The overhand version is much better.
A figure 8 on a bight, (you bite an apple, it's a bight of rope) can invert. It's dangerous.
The overhand is better but back it up.
I still prefer a re-entrant figure 8 and feel more secure with it, but it is more prone to hanging up than the overhand, although not usualy to difficult to untie. I'll use the re-entrant 8 most of the time, but an overhand if it looks like there are potential hangup problems.
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dirtineye
Aug 18, 2003, 9:32 PM
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With one rope there is less friction than with two (assuming they are all the same diameter), so you will go faster or have to hold back more with your brake and guide hand on a single line rappel.
About the knot to join rappel lines, there are a lot of thread about that on this site, for the love of GOD, when will everyone learn that the figure 8 with both tails on the same end of the knot is NOT a good bend, and is in fact very dangerous? People have died rapping on this knot when it rolled off the ends of their ropes.
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