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currupt4130
Sep 6, 2010, 6:01 AM
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Silly question, but I recently bought a pair of half ropes from someone and now need to replace one. They claimed they'd only been used a few times and had a picture. I bought them on MP and figured "Hey, this is a pretty good community, no one is out to screw anyone over." Well I got the ropes and one is perfect the others sheath is shredded about 1/3 of the way from one end with visible core.
So my question is, am I going to be fine with an 8.6 Bluewater and an 8.4 Sterling? I figure it's fine but wanted to ask around anyway before I bought a new rope.
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bill413
Sep 6, 2010, 3:03 PM
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currupt4130 wrote: Silly question, but I recently bought a pair of half ropes from someone and now need to replace one. They claimed they'd only been used a few times and had a picture. I bought them on MP and figured "Hey, this is a pretty good community, no one is out to screw anyone over." Well I got the ropes and one is perfect the others sheath is shredded about 1/3 of the way from one end with visible core. So my question is, am I going to be fine with an 8.6 Bluewater and an 8.4 Sterling? I figure it's fine but wanted to ask around anyway before I bought a new rope.
The advice I've usually heard is that the ropes should be matched. Upon reflection, I'm not sure that this is as important for double/half ropes as it is for twins. Be careful rapelling with them, though, as they will want to move through the rap device at different speeds.
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climboard
Sep 6, 2010, 5:00 PM
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Every piece of literature I have seen from rope manufacturers states that half and twin ropes should be a matching set.
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whipper
Sep 6, 2010, 6:26 PM
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climboard wrote: Every piece of literature I have seen from rope manufacturers states that half and twin ropes should be a matching set.
No shit that manufacturers say that, wouldnt you if you were one? Real world, no, it doesnt matter for doubles. Twins I would care a little, but doubles are clipped to individual pieces, and you are fine. I have climbed on double 10 mil in really sharp areas, and they sure werent the same manufacturer.
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LostinMaine
Sep 6, 2010, 7:10 PM
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whipper wrote: climboard wrote: Every piece of literature I have seen from rope manufacturers states that half and twin ropes should be a matching set. No shit that manufacturers say that, wouldnt you if you were one? Real world, no, it doesnt matter for doubles. Twins I would care a little, but doubles are clipped to individual pieces, and you are fine. I have climbed on double 10 mil in really sharp areas, and they sure werent the same manufacturer.
Climbing on double 10 mils? Wow. Now that's an intense workout.
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whipper
Sep 6, 2010, 7:29 PM
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only did it once on VERY sharp rock. I would not make it a habit at all, but it still reduceses rope drag and is the same as trailing 10 mill rap line.
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malcolm777b
Sep 6, 2010, 8:33 PM
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currupt4130 wrote: Silly question, but I recently bought a pair of half ropes from someone and now need to replace one. They claimed they'd only been used a few times and had a picture. I bought them on MP and figured "Hey, this is a pretty good community, no one is out to screw anyone over." Well I got the ropes and one is perfect the others sheath is shredded about 1/3 of the way from one end with visible core. So my question is, am I going to be fine with an 8.6 Bluewater and an 8.4 Sterling? I figure it's fine but wanted to ask around anyway before I bought a new rope.
If you clip the ropes through the same biner (before splitting the ropes), then there MIGHT be a concern. In a fall, the ropes would stretch differently, and there would be rope on rope friction. I can't imagine how it would be a concern if you always climbed with the ropes split, or used 2 biners/draws on each piece that you wanted to clip both ropes in to.
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clc
Sep 8, 2010, 4:18 AM
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It doesn't really matter if they are the same. I used 8mm with 9mm half ropes. Rappelling is no problem at all, the ropes do not slip differently.
I'm sure some guy will spray a bunch of technical BS why its a bad idea and how dangerous it might be. Well there are safer sports for him.
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JAB
Sep 9, 2010, 7:53 AM
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I once climbed with one single and one half rope in a double rope configuration. It worked perfectly ok, I even took some falls.
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bearbreeder
Sep 9, 2010, 12:07 PM
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you fall on a single rope ... not both
the issue may be feeding ropes out of diff diameter
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clc
Sep 9, 2010, 3:40 PM
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bearbreeder wrote: you fall on a single rope ... not both
Not necessarily true, if you take a big fall both ropes will be weighted.
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bearbreeder
Sep 9, 2010, 3:46 PM
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ahhh ... but one will be weight much more than the other ... the highest should absorb the most shock ...
yr correct though there may be some force on the second rope ... except off the belay when there will be major force on both ropes
as long a they are both certified as half rope i dont see any issue though
(This post was edited by bearbreeder on Sep 9, 2010, 3:48 PM)
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malcolm777b
Sep 9, 2010, 4:40 PM
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bearbreeder wrote: you fall on a single rope ... not both the issue may be feeding ropes out of diff diameter
Not if you are clipping both ropes to one piece!
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bearbreeder
Sep 9, 2010, 4:51 PM
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malcolm777b wrote: bearbreeder wrote: you fall on a single rope ... not both the issue may be feeding ropes out of diff diameter Not if you are clipping both ropes to one piece!
is that advisable with halfs?
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bill413
Sep 9, 2010, 5:07 PM
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bearbreeder wrote: malcolm777b wrote: bearbreeder wrote: you fall on a single rope ... not both the issue may be feeding ropes out of diff diameter Not if you are clipping both ropes to one piece! is that advisable with halfs?
Depends on who you listen to. Don't see it as a problem early in the pitch. Or, of course, right off the belay a fall would weight them both.
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bearbreeder
Sep 9, 2010, 5:10 PM
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yeah i stated that in a subsequent post ... cant catch everything in the morning ... lol
i dont believe its advisable at all to clip 2 half ropes to the same piece ....
if someone wants to show that manufacturers recommend this ... im all ears
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malcolm777b
Sep 9, 2010, 7:38 PM
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bearbreeder wrote: yeah i stated that in a subsequent post ... cant catch everything in the morning ... lol i dont believe its advisable at all to clip 2 half ropes to the same piece .... if someone wants to show that manufacturers recommend this ... im all ears
Read the little brochure that comes with your half ropes. It should tell you that it is ok to use clip half ropes to one piece ala twin rope technique, but once you split the ropes, you must clip each rope to a separate biner if clipping both to the same piece. The point of that being that after split, there are 2 different lengths of rope out. If you clip them to the same biner and fall, one rope will stretch more than the other (due to different lengths), causing rope on rope friction at the biner.
Read this from Mammut:
http://www.mammut.ch/...A457AB48D569015B6797
It doesn't go into the specifics about not bringing them back together after splitting, but DOES say you can climb with half ropes using twin rope technique.
I don't see anyone using halfs this way very often, but good to know why it is acceptable, when you can do it, and what the potential downsides are.
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bearbreeder
Sep 9, 2010, 8:08 PM
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never knew that ... good to know ... thanks
guess ill look at halfs instead of twins ... though it likely increases the force on the piece double clipped
(This post was edited by bearbreeder on Sep 9, 2010, 8:21 PM)
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kennoyce
Sep 9, 2010, 9:04 PM
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In reply to: Read the little brochure that comes with your half ropes. It should tell you that it is ok to use clip half ropes to one piece ala twin rope technique, but once you split the ropes, you must clip each rope to a separate biner if clipping both to the same piece. The point of that being that after split, there are 2 different lengths of rope out. If you clip them to the same biner and fall, one rope will stretch more than the other (due to different lengths), causing rope on rope friction at the biner. Read this from Mammut: http://www.mammut.ch/...A457AB48D569015B6797 It doesn't go into the specifics about not bringing them back together after splitting, but DOES say you can climb with half ropes using twin rope technique. I don't see anyone using halfs this way very often, but good to know why it is acceptable, when you can do it, and what the potential downsides are.
Just want to point out that while this may be fine from the rope manufacturers point of view (i.e. the rope won't break, ane will catch your fall), It certainly is not something that should ever be done. Clipping both ropes into one piece will dramatically increase the forces on that piece should you fall.
For the OP's question, twin ropes should always be the same brand and model, with half ropes it doesn't really matter.
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bill413
Sep 9, 2010, 10:19 PM
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kennoyce wrote: In reply to: Read the little brochure that comes with your half ropes. It should tell you that it is ok to use clip half ropes to one piece ala twin rope technique, but once you split the ropes, you must clip each rope to a separate biner if clipping both to the same piece. The point of that being that after split, there are 2 different lengths of rope out. If you clip them to the same biner and fall, one rope will stretch more than the other (due to different lengths), causing rope on rope friction at the biner. Read this from Mammut: http://www.mammut.ch/...A457AB48D569015B6797 It doesn't go into the specifics about not bringing them back together after splitting, but DOES say you can climb with half ropes using twin rope technique. I don't see anyone using halfs this way very often, but good to know why it is acceptable, when you can do it, and what the potential downsides are. Just want to point out that while this may be fine from the rope manufacturers point of view (i.e. the rope won't break, ane will catch your fall), It certainly is not something that should ever be done. Clipping both ropes into one piece will dramatically increase the forces on that piece should you fall. For the OP's question, twin ropes should always be the same brand and model, with half ropes it doesn't really matter.
Yes - perhaps increase it to the level it would feel with a single fat rope.
Actually, if you are trying to do double rope with one single & one half, this would increase the impact forces on the piece and on you - possibly even past the point of safety.
(This post was edited by bill413 on Sep 9, 2010, 10:20 PM)
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kennoyce
Sep 9, 2010, 11:29 PM
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bill413 wrote: kennoyce wrote: In reply to: Read the little brochure that comes with your half ropes. It should tell you that it is ok to use clip half ropes to one piece ala twin rope technique, but once you split the ropes, you must clip each rope to a separate biner if clipping both to the same piece. The point of that being that after split, there are 2 different lengths of rope out. If you clip them to the same biner and fall, one rope will stretch more than the other (due to different lengths), causing rope on rope friction at the biner. Read this from Mammut: http://www.mammut.ch/...A457AB48D569015B6797 It doesn't go into the specifics about not bringing them back together after splitting, but DOES say you can climb with half ropes using twin rope technique. I don't see anyone using halfs this way very often, but good to know why it is acceptable, when you can do it, and what the potential downsides are. Just want to point out that while this may be fine from the rope manufacturers point of view (i.e. the rope won't break, ane will catch your fall), It certainly is not something that should ever be done. Clipping both ropes into one piece will dramatically increase the forces on that piece should you fall. For the OP's question, twin ropes should always be the same brand and model, with half ropes it doesn't really matter. Yes - perhaps increase it to the level it would feel with a single fat rope. Actually, if you are trying to do double rope with one single & one half, this would increase the impact forces on the piece and on you - possibly even past the point of safety.
from beal's website: "A half rope at 8-kN gives an impact force of 13.5-kN tested as a twin rope, rather more than the resistance of the human body!"
So yes even a half rope used as a twin rope can reach the point of being dangerous under high enough FF falls.
http://www.bealplanet.com/...pe_corde&lang=us
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technogeekery
Sep 10, 2010, 12:22 AM
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Beal Joker 9.1 is certified as single, half/double, and twin. Impact force ratings are :
Single : 8.2kN
Half : 6.0 kN
Twin : 9.6 kN
Bit too skinny for my liking as a single (and I don't climb super-hard sport where it might make a difference) but it looks perfect as a very versatile half rope for long trad climbs where you can use it in half or twin mode, rap full length pitches, and use it as a single to lead on if needed.
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malcolm777b
Sep 10, 2010, 12:36 AM
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kennoyce wrote: bill413 wrote: kennoyce wrote: In reply to: Read the little brochure that comes with your half ropes. It should tell you that it is ok to use clip half ropes to one piece ala twin rope technique, but once you split the ropes, you must clip each rope to a separate biner if clipping both to the same piece. The point of that being that after split, there are 2 different lengths of rope out. If you clip them to the same biner and fall, one rope will stretch more than the other (due to different lengths), causing rope on rope friction at the biner. Read this from Mammut: http://www.mammut.ch/...A457AB48D569015B6797 It doesn't go into the specifics about not bringing them back together after splitting, but DOES say you can climb with half ropes using twin rope technique. I don't see anyone using halfs this way very often, but good to know why it is acceptable, when you can do it, and what the potential downsides are. Just want to point out that while this may be fine from the rope manufacturers point of view (i.e. the rope won't break, ane will catch your fall), It certainly is not something that should ever be done. Clipping both ropes into one piece will dramatically increase the forces on that piece should you fall. For the OP's question, twin ropes should always be the same brand and model, with half ropes it doesn't really matter. Yes - perhaps increase it to the level it would feel with a single fat rope. Actually, if you are trying to do double rope with one single & one half, this would increase the impact forces on the piece and on you - possibly even past the point of safety. from beal's website: "A half rope at 8-kN gives an impact force of 13.5-kN tested as a twin rope, rather more than the resistance of the human body!" So yes even a half rope used as a twin rope can reach the point of being dangerous under high enough FF falls. http://www.bealplanet.com/...pe_corde&lang=us
Yeah, but note ALSO from the same site (and same paragraph), that there was an error in the spec, that it SHOULD be 7kN to meet the equivalent 12kN impact force spec for single/twin ropes. I challenge you to show me a half rope that exceeds 7kN impact force spec in the 55 kg half rope test.
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kennoyce
Sep 10, 2010, 12:47 AM
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In reply to: Yeah, but note ALSO from the same site (and same paragraph), that there was an error in the spec, that it SHOULD be 7kN to meet the equivalent 12kN impact force spec for single/twin ropes. I challenge you to show me a half rope that exceeds 7kN impact force spec in the 55 kg half rope test.
You don't think that an impact force of 12kN or even 11 or 10kN could be dangerous? It might not be enough to rupture a spleen, but could certainly cause gear to rip. My point is that half ropes used as twin ropes can easily increase the impact force to a point where they exceed that of a single rope.
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malcolm777b
Sep 10, 2010, 2:12 AM
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kennoyce wrote: In reply to: Yeah, but note ALSO from the same site (and same paragraph), that there was an error in the spec, that it SHOULD be 7kN to meet the equivalent 12kN impact force spec for single/twin ropes. I challenge you to show me a half rope that exceeds 7kN impact force spec in the 55 kg half rope test. You don't think that an impact force of 12kN or even 11 or 10kN could be dangerous? It might not be enough to rupture a spleen, but could certainly cause gear to rip. My point is that half ropes used as twin ropes can easily increase the impact force to a point where they exceed that of a single rope.
I didn't, and wouldn't say that 10kN is not dangerous, nor that it won't rip gear. I am saying that using half ropes in twin configuration is not inherently dangerous in certain conditions. It is up to the leader to determine when it is dangerous, and when it is advantageous as part of the safety system.
For instance, if there is an easy, incipient crack system that goes straight up for 50 feet with a bomber placement at the top, followed by a sharp flake that the rope would run over near the crux, it could be advantageous to clip the half rope in twin configuration until the sharp flake, then split the ropes, and protect on one strand above the flake. If a fall occurred and one strand was cut, the fall length could be controlled.
Another possible scenario is ledgy terrain with bomber pro. If the leader wants to lessen the possible fall distance (and chance of decking on a ledge), clip the ropes in twin configuration to reduce the total elongation.
The rope tests are pretty extreme, and the impact force numbers are reflective of that. Those scenarios out in the real world are few and far between. Real world impact forces in low factor falls are much less. Again, a competent leader should be able to recognize risk and mitigate accordingly in the overall safety system.
I agree with you that impact forces on gear will be increased when using halfs in twin configuration, but as the numbers for the Joker (posted in this thread) show, twin ropes can cause more impact force than a single as well.
To illustrate my point in a real world situation, I encountered a spot just last week where I decided it was best to clip both half ropes to one piece. There was about 30-40 feet of easy, unprotected climbing off the belay to a slung flake, followed by a 30 foot completely unprotected leftward traverse (including the crux), first over sharp blocks, then over open space. A fall (though unlikely) would have been a nasty swinging fall into a dihedral, but if only one rope was clipped and severed on sharp blocks, it had the possibility of being perilous to the entire team, as the belay was fairly precarious (a not so stout tree with nothing to back it up). This was the first time that I had decided to use my half ropes in twin configuration, and I was glad to have the option.
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