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oldguy
Jan 25, 2005, 6:24 PM
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I recently watch one of "Masters" videos. A couple of times in it, a nut was placed and a biner was used to connect directly between the wire and the rope. I was under the impression that something soft (a sling) was always needed between the pro and the rope to prevent the rope action from dislodging the pro. However, I can see that if the nut is jammed in tight it shouldn't be much of a concern.
So what's the deal. Is this a good placement or not?
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tradklime
Jan 25, 2005, 6:33 PM
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Of course the answer is "it depends". I'd always just put a quick draw on there just to feel better about it, even if just a shorty. I can't imagine 6 inches would make that much of a difference, other than for the better.
I suppose it could be less of an issue with pre-placed gear, or fixed nuts that are "welded" into place.
This could also fall into the "if you have to ask, don't do it" catagory.
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dirtineye
Jan 25, 2005, 7:17 PM
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Instead of asking for the answer, try this experiment:
place a nut. clip a biner directly to it and clip the rope. Now shake the rope around and see what happens. Try pulling outward on the rope. See what happens.
Try again with a sling between the pro and the rope.
Note your results.
Repeat many times with different placements and different sling lengths.
Report back with your results.
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vegastradguy
Jan 26, 2005, 3:59 AM
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considering it was on a video...it was 1) staged and 2) probably in the 5.12-5.13 range, meaning steep, perfectly straight, and 3) gear was probably set up such that clipping it directly to the rope was the only option for the climber to not fall
however, for mere mortals, wires should always have some sort of a draw on them. cams should to, unless you're climbing a perfectly straight pitch.
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ryan112ryan
Jan 26, 2005, 5:09 AM
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In reply to: however, for mere mortals, wires should always have some sort of a draw on them. cams should to, unless you're climbing a perfectly straight pitch.
could you elaborate on what you mean by straight up pitch?
second, i have always wondered about what size slings to choose for leading. from what i gathered you use a sling, when you have to place a peice off to the side of your intended line up the face (route). you choose a sling that is long enough to bring the rope back in line with your route. this allows for reduced rope drag, and allows less direct movement and force on the peice. is this correct????
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petsfed
Jan 26, 2005, 5:20 AM
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In reply to: In reply to: however, for mere mortals, wires should always have some sort of a draw on them. cams should to, unless you're climbing a perfectly straight pitch. could you elaborate on what you mean by straight up pitch? second, i have always wondered about what size slings to choose for leading. from what i gathered you use a sling, when you have to place a peice off to the side of your intended line up the face (route). you choose a sling that is long enough to bring the rope back in line with your route. this allows for reduced rope drag, and allows less direct movement and force on the peice. is this correct????
The idea is that the path of the rope is as straight as possible. Less rope drag means two things: less rope drag so you don't have to fight as much friction going up, less rope movement which may cause seemingly good placements to walk into less good placements. Obviously this isn't always possible given certain situations (eg traversing above a ledge, etc) so you use what works best given the situation which may include clipping the piece directly. Better to be flexible to the situation than to blindly follow dogma, but take that with a grain of salt eh?
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dirtineye
Jan 26, 2005, 5:25 AM
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In reply to: In reply to: however, for mere mortals, wires should always have some sort of a draw on them. cams should to, unless you're climbing a perfectly straight pitch. could you elaborate on what you mean by straight up pitch? second, i have always wondered about what size slings to choose for leading. from what i gathered you use a sling, when you have to place a peice off to the side of your intended line up the face (route). you choose a sling that is long enough to bring the rope back in line with your route. this allows for reduced rope drag, and allows less direct movement and force on the peice. is this correct????
Yes it is.
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ryan112ryan
Jan 26, 2005, 5:29 AM
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In reply to: In reply to: In reply to: however, for mere mortals, wires should always have some sort of a draw on them. cams should to, unless you're climbing a perfectly straight pitch. could you elaborate on what you mean by straight up pitch? second, i have always wondered about what size slings to choose for leading. from what i gathered you use a sling, when you have to place a peice off to the side of your intended line up the face (route). you choose a sling that is long enough to bring the rope back in line with your route. this allows for reduced rope drag, and allows less direct movement and force on the peice. is this correct???? Yes it is.
any further considerations? do most people use lockers from the nut wire, to the sling, then the sling to the rope. what tension should these slings be?
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dirtineye
Jan 26, 2005, 5:40 AM
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Ideally, the only pieces that should take any force at all are the top piece and the bottom anti zippering piece.
Almost nobody follows this excellent advice.
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maculated
Jan 26, 2005, 6:24 AM
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In reply to: any further considerations? do most people use lockers from the nut wire, to the sling, then the sling to the rope. what tension should these slings be?
Lockers rarely find themselves on protection placements (rarely because sometimes they just happen to be on my sling of choice at the time). Most people, and by this I mean all people, use a sling with two normal biners (although one could certainly be bent gate for the rope end if you're worried about it).
The tension question throws me. No entiendo.
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ryan112ryan
Jan 26, 2005, 5:43 PM
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In reply to: In reply to: what tension should these slings be? Tension indicates that there is friction on the biner dragging it away from the pro, so you ideally want minimal tension on the slings. That's the whole purpose of extending the placement.
wouldn't you want a sling that is just long enough to bring the rope back into the line of your route? if its longer, the runner will be loose, but if you were to fall you would fall furthur than with a shorter runner?.
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blueeyedclimber
Jan 26, 2005, 5:58 PM
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In reply to: Ideally, the only pieces that should take any force at all are the top piece and the bottom anti zippering piece. Almost nobody follows this excellent advice.
No, ideally you want all placed pieces to share the load. The top and bottom will obviously take a majority of it, but ideally you would like all of your pieces to go taut in the event of a fall, increasing the friction and decreasing the amount of force that the top one has to take.
Josh
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caughtinside
Jan 26, 2005, 6:11 PM
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In reply to: In reply to: Ideally, the only pieces that should take any force at all are the top piece and the bottom anti zippering piece. Almost nobody follows this excellent advice. No, ideally you want all placed pieces to share the load. The top and bottom will obviously take a majority of it, but ideally you would like all of your pieces to go taut in the event of a fall, increasing the friction and decreasing the amount of force that the top one has to take. Josh
Where did you get that idea?
The middle pieces won't be taking any up and down force. They will only be pulled from side to side if they are out of line with the rope. This may compromise those placements.
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dirtineye
Jan 26, 2005, 6:38 PM
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In reply to: In reply to: In reply to: Ideally, the only pieces that should take any force at all are the top piece and the bottom anti zippering piece. Almost nobody follows this excellent advice. No, ideally you want all placed pieces to share the load. The top and bottom will obviously take a majority of it, but ideally you would like all of your pieces to go taut in the event of a fall, increasing the friction and decreasing the amount of force that the top one has to take. Josh Where did you get that idea? The middle pieces won't be taking any up and down force. They will only be pulled from side to side if they are out of line with the rope. This may compromise those placements.
Thanks caughtinside.
Josh, you don't understand. Your 'method' is downright dangerous. It is also just plain wrong. People hit the ground because they did what you suggest.
Have you ever heard of or seen the zippering effect? How do you think this happens? What do you think lifts nuts out, or walks cams into fixed gear or failure?
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blueeyedclimber
Jan 26, 2005, 8:17 PM
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In reply to: In reply to: In reply to: Ideally, the only pieces that should take any force at all are the top piece and the bottom anti zippering piece. Almost nobody follows this excellent advice. No, ideally you want all placed pieces to share the load. The top and bottom will obviously take a majority of it, but ideally you would like all of your pieces to go taut in the event of a fall, increasing the friction and decreasing the amount of force that the top one has to take. Josh Where did you get that idea? The middle pieces won't be taking any up and down force. They will only be pulled from side to side if they are out of line with the rope. This may compromise those placements.
That's not what I said. I said they will take some of the load. When you place a piece, you place to accept, at the least, a downward and OUTWARD pull. In a fall, the rope goes taut pulling the pieces outward. A lot of these pieces accept friction and some of the energy. These pieces are not the critical ones of the first and last, but no one rests there life on one piece, but the system as a whole. That is what I meant. I am not sure how i am wrong, but please explain it to me.
Josh
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dirtineye
Jan 26, 2005, 8:49 PM
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Holy Mother of Pearl, is this bizzaro world climbing?
Since you, blue eyed climber, did not bother to read or thinbk about the other questions I gave you, I doubt this one wil ldo much good either, but, suppose for a minute that your way is OK.
You fall, and all your pieces shift. Then the top piece blows.
Now what do you think will happen? Do you really want the pieces below the top one to have shifted and then take the fall force after the original top piece blows?
Second scenario:
Geared as you stated, you fall, and the pieces under the top piece pop out because of the outward pull. Are you a happy climber now?
I'm starting to wonder if you have ever seen a cam walk or a nut lift.
Maybe someone else can explain it to you better, I give up.
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caughtinside
Jan 26, 2005, 8:57 PM
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How is the piece second from the top going to take outward pull? The rope is running from there to the top, not out.
If the pieces in the middle are taut on the rope, most likely the rope is pulling out on them. Sometimes, this can be unavoidable. Sometimes, this won't affect the placement.
But it is absorbing a negligible amount of the force of the fall, especially in comparison to the risk it poses in having those pieces shift/walk into bad spots. Either getting fixed, or getting loose/falling out.
Plus, what dirtineye said.
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blueeyedclimber
Jan 26, 2005, 9:32 PM
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In reply to: How is the piece second from the top going to take outward pull? The rope is running from there to the top, not out. If the pieces in the middle are taut on the rope, most likely the rope is pulling out on them. Sometimes, this can be unavoidable. Sometimes, this won't affect the placement. But it is absorbing a negligible amount of the force of the fall, especially in comparison to the risk it poses in having those pieces shift/walk into bad spots. Either getting fixed, or getting loose/falling out. Plus, what dirtineye said.
Yes, I understand this, but your pieces are set to take outward pull, I said nothing about upward pull. When you fall you fall, outward and downward. I think you misunderstood what I said. I place a piece to catch me if i fall (the top piece). As I climb, and put in more pieces set to anticipate the direction of pull. But when i fall, all those middle pieces Do play a role in the absortion of force. Maybe I overstated how much, but they do play a role. I never said that these pieces are catching my fall.
Usually pieces walk becasue of the UPWARD pull of the rope, not out ward, although this could happen as well.
Josh
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cracklover
Jan 26, 2005, 10:32 PM
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Sorry, Josh, much as I like you, I gotta call BS on this one.
1 - It's easy for a piece to get pulled *up*. Let's say piece # 1 is mostly to the right, piece # 2 is in the middle, and piece # 3 is up and slightly to the left. The draw on piece # 2 will be pulled up and to the right.
2 - Nylon and spectra runners absorb almost no force. On the contrary, the more the rope zigs and zags, the more force the top piece feels. This is because the friction of the rope going through each of those biners between the belay device and the top piece reduce the rope stretch, resulting in a practical case of higher fall factor. For more info, see the Petzl page that discusses their experiments on the topic.
In short, the closer you can get to a straight line with the biners on the rope, the better.
One exception: When I am at a crux where a fall might land me on a ledge or the ground, and the sling may make that difference, I sometimes will skip the sling, and just use a single locking biner. Or as Dizzy says: "A full length 'biner".
GO
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caughtinside
Jan 26, 2005, 10:38 PM
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In reply to: Usually pieces walk becasue of the UPWARD pull of the rope, not out ward, although this could happen as well.
Outward pull can rotate a cam easily. Then, it's not in position to catch a downward fall, or the rotation can walk it in deeper. Outward pull can shift your nuts, loosen them in place, or pull them out.
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blueeyedclimber
Jan 27, 2005, 12:17 AM
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I pretty much agree with all of you, but it is still not what i meant. I guess I will try one more, it's been fun.
I know I will get flamed for bringing a sport reference into the trad forum, but it may help my case.
In sport you don't really need to worry about the line of the rope because it's been done for you. With that said, when you fall, do all of the draws between the top and bottom get pulled by the rope or do they hang loose? THey get pulled out, Because the rope is in a straight line. Would the top draw have more force put on it if these "middle" draws are there or if they aren't. If there is only one draw to fall on, it will have more force put on it then if you are a dozen draws up.
That is all I was saying.
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caughtinside
Jan 27, 2005, 12:33 AM
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YOu can't compare bolts to gear. Otherwise, you wouldn't clip runners to gear. Bolts are multidirectional, gear isn't.
I see what you're saying. Yeah, if you fall, and the runner attached to your gear is pulled taut, the friction of that biner on the rope is going to absorb a small amount of energy. And it's also going to put force on your piece, perhaps moving or rotating it.
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blueeyedclimber
Jan 27, 2005, 12:44 AM
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In reply to: YOu can't compare bolts to gear. Otherwise, you wouldn't clip runners to gear. Bolts are multidirectional, gear isn't. I see what you're saying. Yeah, if you fall, and the runner attached to your gear is pulled taut, the friction of that biner on the rope is going to absorb a small amount of energy. And it's also going to put force on your piece, perhaps moving or rotating it.
Phew! Yes, I know you can't compare the two, but you see what I mean now, right? I brought up that reference so no one could talk about line of rope, because it isn't an issue in sport. Sorry about the confusion. I dont' know the numbers, but i am not sure the amount of energy absorbed is as small as you think. We need a physicist here.
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climbinginchico
Jan 27, 2005, 12:50 AM
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In reply to: In reply to: In reply to: what tension should these slings be? Tension indicates that there is friction on the biner dragging it away from the pro, so you ideally want minimal tension on the slings. That's the whole purpose of extending the placement. wouldn't you want a sling that is just long enough to bring the rope back into the line of your route? if its longer, the runner will be loose, but if you were to fall you would fall furthur than with a shorter runner?.
In general, in trad climbing, this isn't that much of an issue unless there is a ledge or something. In which case, use a shorter one if you're gonna fall. There shouldn't be tension on the slings because it can cause the piece to walk, or shift, possibly reducing the effectiveness of the placement. The purpose of extending the placement is to keep it from walking.
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aikibujin
Jan 27, 2005, 2:19 AM
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In reply to: In sport you don't really need to worry about the line of the rope because it's been done for you. With that said, when you fall, do all of the draws between the top and bottom get pulled by the rope or do they hang loose? THey get pulled out, Because the rope is in a straight line. Would the top draw have more force put on it if these "middle" draws are there or if they aren't. If there is only one draw to fall on, it will have more force put on it then if you are a dozen draws up.
I am not a physist, but I did read a physics textbook once... or was it an Spanish textbook? Anyway, here's my $0.02: suppose if all the bolts (or the pieces of pro) runs in a straight vertical line, and your belayer is standing right next to the rock directly under the first bolt (or piece). Then when you fall, all the draws except the very top one will stay loose. But of course, that's an exceptional case.
When you fall, if the belay is totally static with zero slip (happens only in theory), the rope slip through the biners a little from rope stretch, but how much energy this absorbs is debatable. Especially considering the friction in the biners effectively reduce the amount of rope out to absorb more energy.
If the belay is dynamic, then all the added friction in the system MAY actually reduce a considerable amount of energy. However, this is also debatable, and weighing the benefit of reduced impact force with the risk of pulling out gear in a non-anticipated direction of pull, I think the risk outweighs the benefit.
But that's just my opinion.
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cracklover
Jan 27, 2005, 4:13 AM
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In reply to: Would the top draw have more force put on it if these "middle" draws are there or if they aren't. If there is only one draw to fall on, it will have more force put on it then if you are a dozen draws up. That is all I was saying.
I understand what you are saying perfectly well. The problem is that what you are saying is dead wrong. When the rope runs directly from the top piece to the belayer, the entire rope is available to absorb the force of a fall. The more friction in the system between the top piece and the belayer, the less the rope towards the bottom will stretch. The less the rope stretches, the shorter the stopping distance. The shorter the stopping distance, the higher the peak force on the top piece. For some reason you are refusing to believe this fact.
There are test results available online if you don't believe me.
GO
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jakedatc
Jan 27, 2005, 4:23 AM
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oo sport in the trad forum... myself the sport weenie Loves this...
Not all sport climbs are bolted in a straight line.. some very much not...and not all the draws will be tight all the time..
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johnnord
Jan 27, 2005, 5:11 AM
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In reply to: In reply to: Would the top draw have more force put on it if these "middle" draws are there or if they aren't. If there is only one draw to fall on, it will have more force put on it then if you are a dozen draws up. That is all I was saying. I understand what you are saying perfectly well. The problem is that what you are saying is dead wrong. When the rope runs directly from the top piece to the belayer, the entire rope is available to absorb the force of a fall. The more friction in the system between the top piece and the belayer, the less the rope towards the bottom will stretch. The less the rope stretches, the shorter the stopping distance. The shorter the stopping distance, the higher the peak force on the top piece. For some reason you are refusing to believe this fact. There are test results available online if you don't believe me. GO
I need some help with this one.
Assume two climbs. The first climb has one piece 50' up. The rope absorbs the force of the fall and the top piece is subjected to "x" amout of force. In the second climb there is on piece between the top piece and the belayer. In the event of a fall the rope and the intermediate piece both the absorb the force of fall. Why is the amount of force on the top anchor greater than "x"? The reason the stopping distance (function of rope stretch) is less is because the force on the rope has been reduced (albeit minimally) by the intermediate piece. I'll check with my physicist friend tomorrow and ask him. (IMHO I don't thing the amout of friction added by intermediate pieces on a relatively vertical climb amounts to much)
Also, if there are intermediate pieces acting on the rope, doesn't that mean that there is more rope out and therefore more force being absorbed by the rope?
Also, does the rope stretch differently at the bottom as you suggest, or does the rope spread the force over the entire length of the rope?
Can you give the URL for the online source you refer to?
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david.yount
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Jan 27, 2005, 5:20 AM
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In reply to: In reply to: Would the top draw have more force put on it if these "middle" draws are there or if they aren't. If there is only one draw to fall on, it will have more force put on it then if you are a dozen draws up. That is all I was saying. I understand what you are saying perfectly well. The problem is that what you are saying is dead wrong. When the rope runs directly from the top piece to the belayer, the entire rope is available to absorb the force of a fall. The more friction in the system between the top piece and the belayer, the less the rope towards the bottom will stretch. The less the rope stretches, the shorter the stopping distance. The shorter the stopping distance, the higher the peak force on the top piece. For some reason you are refusing to believe this fact. There are test results available online if you don't believe me. GO
yep, what he said.
i've never watched a climbing video. with a title like "Masters" i wonder if this video featured a few clips of 70's climbers? it was common to use a single biner to clip the rope to the placement. often two biners were used. slings weren't common.
but now since nylon webbing is cheap and plentiful (and spectra/dyneema is truly delightful) most placements are improved with a runner.
ideally the lead climbing rope should run in a straight line. long runners help to keep the rope line straight, even when the climbing line is not straight. i usually prefer to use a longer runner to keep my rope straight and accept the fact that longer a longer runner will increase my fall if i were to fall on that longer runner.
if the rope does not experience any zig zags then the entire belay length can help to absorb falling force, making the maximum load at the top piece as small as can be. reducing the load at the top piece in case of a fall is certainly a priority goal for me.
if the rope does not experience any zig zags then placements will be best protected from jiggling forces from rope movement. i make very careful placements and i don't want them to move.
if the rope does not experience any zig zags then rope drag is minimized and i'm having a more enjoyable time lead climbing.
david yount.
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shutupandclimb
Jan 27, 2005, 5:27 AM
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You are saying that a short runner on a lower piece is pointing straight out in a fall. But if it were to take some force off the belayer it would have to be taking an upward pull.
Thinking in vectors, pulling a piece close to straight out, the downward pull from the piece is going to be very small compared to the outward pull. For any noticable amount of energy absorbed by that piece it would have to take an upward pull.
The energy absorbed by the top piece will be the same with either a short draw or long runner, but with a long runner it is absorbed by the belayer instead of the lower pieces. Get some runners and a soft catch.
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tradklime
Jan 27, 2005, 3:33 PM
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For those who are having trouble with this, here's the deal...
You want as little friction in the system as possible so that the rope can do it's job. In simplistic terms, the ropes job is absorbing the force of a fall. Friction is introduced by the rope zig-zaging, running tight over buldges, etc. In a perfect world, in a fall, the rope would only be tight against the biner attached to the piece catching the fall. The rope should run freely through the other pieces of protection, if it does not, you are isolating (at least partially) portions of the rope that won't be able to do its job. The more rope available to absorb force, the better.
Another benefit of reducing friction is reducing the amount of drag on the climber as they move upward.
Sorry to repeat what others have said, but hopefully this will put the questions to rest.
As a side note, this is of course over simplified because you may want some sort of redirection at the first piece to avoid zippering. But that's another topic.
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cracklover
Jan 27, 2005, 3:43 PM
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In reply to: In reply to: In reply to: Would the top draw have more force put on it if these "middle" draws are there or if they aren't. If there is only one draw to fall on, it will have more force put on it then if you are a dozen draws up. That is all I was saying. I understand what you are saying perfectly well. The problem is that what you are saying is dead wrong. When the rope runs directly from the top piece to the belayer, the entire rope is available to absorb the force of a fall. The more friction in the system between the top piece and the belayer, the less the rope towards the bottom will stretch. The less the rope stretches, the shorter the stopping distance. The shorter the stopping distance, the higher the peak force on the top piece. For some reason you are refusing to believe this fact. There are test results available online if you don't believe me. GO I need some help with this one.
Okay, I'll do my best.
In reply to: Assume two climbs. The first climb has one piece 50' up. The rope absorbs the force of the fall and the top piece is subjected to "x" amout of force. In the second climb there is on piece between the top piece and the belayer. In the event of a fall the rope and the intermediate piece both the absorb the force of fall.
The top piece and the intermediate piece do "absorb" some energy (more specifically they change energy from kinetic to heat through friction). But a larger issue comes from the fact that those biners are reducing the amount the rope can stretch. Let's take an extreme case. Lets say that you put a munter hitch around your top piece. Do you see that now any fall would turn into something approximating a factor two fall? So as any biners in the system add friction, you come closer to this absolute.
In reply to: Why is the amount of force on the top anchor greater than "x"? The reason the stopping distance (function of rope stretch) is less is because the force on the rope has been reduced (albeit minimally) by the intermediate piece. I'll check with my physicist friend tomorrow and ask him. (IMHO I don't thing the amout of friction added by intermediate pieces on a relatively vertical climb amounts to much)
It's not how vertical the climb is that matters, but the amount of friction in the system, due to either zig-zagged rope through biners, or around overhangs or corners.
In reply to: Also, if there are intermediate pieces acting on the rope, doesn't that mean that there is more rope out and therefore more force being absorbed by the rope?
Good question. As it turns out, the extra rope cannot absorb any extra force, because of the extra friction. If the biners were all frictionless pulleys, I suspect you'd be right, though I haven't thought that one through.
In reply to: Also, does the rope stretch differently at the bottom as you suggest, or does the rope spread the force over the entire length of the rope?
Um, you're asking me?
In reply to: Can you give the URL for the online source you refer to?
I cannot find one right now, but I noticed that since the research came out, the petzl fall simulator added an option to put in zig-zagged protection, so you can see how that impacts the forces on your protection. Here is a link to their site. (Be patient, it loads quite slowly.)
Hope that's helpful.
GO
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sarcat
Jan 27, 2005, 3:55 PM
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VERY informative thread. Thanks to david.yount. excellent post.
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aikibujin
Jan 27, 2005, 4:03 PM
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In reply to: a fall. The more friction in the system between the top piece and the belayer, the less the rope towards the bottom will stretch. The less the rope stretches, the shorter the stopping distance. The shorter the stopping distance, the higher the peak force on the top piece. There are test results available online if you don't believe me.
In reply to: I cannot find one right now, but I noticed that since the research came out, the petzl fall simulator added an option to put in zig-zagged protection, so you can see how that impacts the forces on your
Here is one web site that I've found that explains this: www.impact-force.info, it is created by Beal Ropes. It talks about this phenomenon in terms of theoretical fall factor vs actual fall factor.
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cracklover
Jan 27, 2005, 4:24 PM
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In reply to: Here is one web site that I've found that explains this: www.impact-force.info, it is created by Beal Ropes. It talks about this phenomenon in terms of theoretical fall factor vs actual fall factor.
Yes, that's quite nice, thanks. There appears to be a mistake in the single-rope drawing on page 5, though. I believe the left-hand of the two drawings is supposed to show a rope without extended runners, like the left-hand of the two drawings in figure 2 (the half-rope illustration).
GO
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blueeyedclimber
Jan 27, 2005, 5:07 PM
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OK, Gabe, I understand now. Although, I think my thinking was correct, I was not factoring in the loss of rope stretch which I guess trumps my point. None of the posts until yours actually dealt with what i was saying, though. Just so i am clear, are you saying that putting more pieces in could actually increase the force on your top piece? Unless of course, the rope is in a perfectly straight line from your belayer to the top piece.
Josh
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dirtineye
Jan 27, 2005, 5:21 PM
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Unbelieveable.
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caughtinside
Jan 27, 2005, 5:23 PM
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In reply to: Unbelieveable. |
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blueeyedclimber
Jan 27, 2005, 5:27 PM
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In reply to: Unbelieveable.
Back at ya! :roll:
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dirtineye
Jan 27, 2005, 5:37 PM
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The main issue is not the outward pull helping or not helping to absorb fAll force , or the rope stretch, although these things are pertinent, rather, it is the PULLING OF PIECES that could lead to death or injury.
I know people that have hit the ground because they did what you think is correct.
I've seen gear shift, lift and walk in or out because of people doing what you think is correct.
You don't have to believe any of us, you can read about proper gear sling extension in a number of good climbing books.
For your own safety, drop this goofy idea and avoid rope drag as much as possible.
And for the person who thinks a cam will not walk out of a crack and fail, all it takes is a cam on a short sling in a crack that gets wider to the rear and a little drag for that cam to walk in and fall out the bottom. This has happened to a friend of mine. There are other situations where a cam can walk to failure as well.
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blueeyedclimber
Jan 27, 2005, 5:49 PM
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In reply to: The main issue is not the outward pull helping or not helping to absorb fAll force , or the rope stretch, although these things are pertinent, rather, it is the PULLING OF PIECES that could lead to death or injury. I know people that have hit the ground because they did what you think is correct. I've seen gear shift, lift and walk in or out because of people doing what you think is correct. You don't have to believe any of us, you can read about proper gear sling extension in a number of good climbing books. For your own safety, drop this goofy idea and avoid rope drag as much as possible. And for the person who thinks a cam will not walk out of a crack and fail, all it takes is a cam on a short sling in a crack that gets wider to the rear and a little drag for that cam to walk in and fall out the bottom. This has happened to a friend of mine. There are other situations where a cam can walk to failure as well.
Are you just trying to get the last word in? I wasn't talking about rope drag. Everything you are saying right now, I AGREE, and let's leave it at that.
Josh
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cracklover
Jan 27, 2005, 6:16 PM
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In reply to: Just so i am clear, are you saying that putting more pieces in could actually increase the force on your top piece? Unless of course, the rope is in a perfectly straight line from your belayer to the top piece. Josh
Yes. Of course this can be mitigated by proper length slings. Or, for pitches that really wander, double rope technique. And as dirt is so fond of mentioning (and david.yount gave excellent examples of), this has many other important ramifications.
If you're curious to see how the force on your top piece might meet or exceed the rating of that gear in practice, go to the petzl fall simulator link I referenced above. As I mentioned, it now has a parameter that will allow you to simulate a zig-zagged rope.
GO
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piton
Jan 27, 2005, 6:17 PM
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oppose you first placement and make the belayer stands close to wall, not 10 ft back. this will help limit you outward
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healyje
Jan 28, 2005, 10:15 AM
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In reply to: oppose you first placement and make the belayer stands close to wall, not 10 ft back. this will help limit you outward [pull]
Just to be very clear here - Piton is giving you good advice here, but I want to make sure it is understood that the advice has two parts that prevent different problems.
The first is a solution to help prevent zippering your line of pro (e.g. limit outward pull on pieces above the first piece) the statement above should probably simply read:
In reply to: oppose you first placement, this will help limit you outward [pull]
The second has more to do with how much load is being applied to that first omni-directional piece that is preventing the line from zippering. That part of the statement is:
In reply to: ...and make the belayer stands close to wall, not 10 ft back.[pull]
Again, the point here is to reduce the load on that first critical piece that is preventing the line from zippering. A second benefit of belaying close to that first piece is that in the event of a high force fall you, as a belayer won't get drug towards the wall at a fast rate with the climber falling that much more as you come into the wall.
For that matter, even if you are quite close to the wall as a belayer, if your stance isn't well braced I've seen belayers slammed into a wall 2 feet away so hard their hands untensioned on the rope resulting in both a bad fall for the leader and 2nd / 3rd degree burns for the belayer from the rope screaming through their hands. Never underestimate this inward dynamic.
Again, the whole point of putting in that first omni-directional piece is to prevent zippering - if you then stand back from it any real distance you are now jeapardizing that critical placement and the whole line of pro. You put it at risk both by the increased load on it and due to the fact that the line will attempt to zipper if the first placement fails while you're way back. So make sure that first piece is bombers and stick close to it in a solid stance that anticipates a good solid yank straight in towards it.
And Josh, dirtineye isn't simply trying to get in a last word, he's actually just trying to make sure you understand the whole concept clearly after all this winding discussion. He's doing that because he knows how important it is to have an excruciatingly clear understanding of the desired lead mechanics which are:
a) First piece off the belay is omni-directionally bomber
b) All subsequent pieces are slinged appropriately or put in opposition to either eliminate or minimize [the] rope pull on the piece as you climb past it.
[Note: If the line of pro is still going to zig-zag badly then you need to switch to a two-rope lead to elminate the zig-zagging (two-rope leading requires advanced belaying skills and technique).]
c) The "perfect" mechanical scenario is a straightline for the rope in a fall such that only the last piece, first piece, and belay device carry the load while all intermediary pieces (and slings) remain untensioned and unloaded.
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cantbuymefriends
Jan 28, 2005, 1:39 PM
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In reply to: Are you just trying to get the last word in? I wasn't talking about rope drag. Everything you are saying right now, I AGREE, and let's leave it at that. Josh
I think he has every dang right in the world to "just" try to get the last word in! Just to make it perfectly clear to everybody that what you have stubbornly stated throughout this thread is not just wrong, it's also PLAIN EFFIN' DEADLY DANGEROUS!!!
If someone actually listened to what you said, and where to pull a top piece and deck because of the increased rope drag, what would you say?
"Oh, rope stretch? Sorry, didn't think of that! But besides that I think my thinking was correct."
In reply to: Just so i am clear, are you saying that putting more pieces in could actually increase the force on your top piece?
In one word: YES! (I know it's been said earlier, I just wanted to reinforce it.)
(End of ranting. Sorry, 'bout that. Got a bit carried away by such fundamental misunderstanding of one of the most important pieces of safety principles in climbing...)
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blueeyedclimber
Jan 28, 2005, 3:22 PM
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I am getting the last word in and you'll be happy to know it is me EATING CROW!
A lot of what was brought up I already knew and didn't answer my question so sorry I got upset. I see my obvious error now and it has made me a better(safer) climber. Thank you. Although Gabe was the only polite one, it's only because he knows me and I (bragging a little) am a very likeable guy. I was not trying to bs anyone, just thinking about a concept I thought was correct, while not thinking about some other things.
Once again, I am glad you all spoke up and just so you know I do have common sense and do have a lot of knowledge, but also realize that I have a lot still to learn. I am also on edge because Spring seems so far away.
Thanks, Josh
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hugepedro
Jan 28, 2005, 4:32 PM
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In reply to: Just so i am clear, are you saying that putting more pieces in could actually increase the force on your top piece? Unless of course, the rope is in a perfectly straight line from your belayer to the top piece.
Just so it's clear, it doesn't matter how many pieces you put in. How much rope drag you build into your system does matter.
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dingus
Jan 28, 2005, 4:44 PM
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People have been clipping biners directly to wired nuts since they were invented. People have not been dying in droves as a result. Zippering, rope drag and all other considerations (all worthy and should of course be taken into consideration) aside, there is nothing inherently unsafe about clipping a biner to the nut and dropping the rope into the basket, as long as you are aware of the limitations and work to mitigate them.
Simple as that really.
Me? I pretty much put runners of some kind on every placement unless I feel the extra 2-6 feet of fall distance potential poses a problem. When I do clip directly I tend to set the hell out of the nut (nut tool required for extraction). In fact, and I really don't care if my partner is offended or not, I tend to set the hellouta every nut I place)
Later!
DMT
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dirtineye
Jan 28, 2005, 5:18 PM
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Sorry if I was impolite, but as healyj and I think some others pointed out, it's an attempt to keep your eyes blue as opposed to vacant.
I really hate reading those accident reports that go like this: Two pieces pulled and so-and-so was seriously injured (or dead).
I'm sure you are a nice guy, most people you meet climbing are. Sometimes the internet leads all of us to come off less favorably than we do in person, I know I'm guilty.
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dirtineye
Jan 28, 2005, 5:50 PM
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To adapt a bit of programming lore, "If it was hard to place, it should be hard to clean." HEHE. Not really, but it sounds good.
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blueeyedclimber
Jan 28, 2005, 6:12 PM
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In reply to: Sorry if I was impolite, but as healyj and I think some others pointed out, it's an attempt to keep your eyes blue as opposed to vacant. I really hate reading those accident reports that go like this: Two pieces pulled and so-and-so was seriously injured (or dead). I'm sure you are a nice guy, most people you meet climbing are. Sometimes the internet leads all of us to come off less favorably than we do in person, I know I'm guilty.
Apology accepted. And you are right on all counts. Although a lot of the things brought up I knew that I was supposed to do, this thread gave me a better understanding of the reasoning behind it. A while (not sure how long), I posted something about whether rc.com was useful or just entertainment. Although most of it is purely entertainment, I do come away with some important information. A little here and a little there is important to keep us safe. You mentioned that the internet sometimes makes us appear less favorable, well, it also sometimes makes us appear less bright.
Happy climbing!
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healyje
Jan 28, 2005, 7:14 PM
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In reply to: In reply to: When I do clip directly I tend to set the hell out of the nut (nut tool required for extraction). Ditto. Also, and I think this is important, I'll use a locking 'biner on the piece.
I agree with Dingus about not hesitating to clip directly into a wired piece with just a single biner; but when I do clip directly into a piece of pro, I usually do it with 2 biners, not one; but, hell, if you're running low on them, you're running low. With regard to specifically using a locker in this scenario - it might be somewhat reassuring, but I don't believe it is at all necessary.
Also, I rarely if ever "set" my pro at all, even in this type of instance unless I'm sure rope is going to jack it around.
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dingus
Jan 29, 2005, 1:18 AM
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In reply to: Also, I rarely if ever "set" my pro at all, even in this type of instance unless I'm sure rope is going to jack it around.
I've always respected you gentle nutters. It demonstrates a cool mind, a calm, calculating demeanor. Cerebral even.
My nut craft is much more animal bro. I sniff the crack, probe it with my digits, and grunting, I root among the shiney things hanging off my collar. I get that nut in there and whining, I yank, sometimes soft, sometimes hard, panic hard, ohgodpleasedontlethisnutfailphluuuuzzzzeeedontlethisnutliftoutwheniclimbaboveitohpleeeeeeze!
Now I know this is happened to you cause it has happened to us all, ya boldly run it out up some easy shit and then make a few decent moves into the business. You pause and carefully place that nut and clippity clip on you go. Despite all your care you accidently kick the draw on the nut and lift it out slick as you please, mid crux, facing the lovelies, eh?
That's about 5.4 for me but you know what I mean.
Flashbacks of that'll having ya paying attention to those nuts. Like a dog in my case, sniff sniff sniff yank.
DMT
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healyje
Jan 29, 2005, 7:48 AM
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In reply to: Now I know this is happened to you cause it has happened to us all, ya boldly run it out up some easy s--- and then make a few decent moves into the business. You pause and carefully place that nut and clippity clip on you go. Despite all your care you accidently kick the draw on the nut and lift it out slick as you please, mid crux, facing the lovelies, eh?
You know it! Hey, if a piece isn't inclined to just damn well sit there and cooperate; and there is no opposition - then I set it hard, as in just this side of bounce testing it. It rarely happens as again I try to never set my pro, depending instead on the placement and slingage to keep it in place. But sometimes it happens and I don't stand on ceremony.
And cleaning it - screw my second, though he has my o.k. to just leave the damn thing for fixed if it comes down to that...
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dirtineye
Jan 29, 2005, 5:55 PM
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YOu know how old climbing partners talking about each other's pro placements can sould like two old women fussing over how to take care of a baby?
Well I was with two great southern climbers once, they had climbed together for many years, and one had done a very nice crack on nothing but nuts. This crack took nuts like pancakes take butter and maple syrup. THey started out with two oppposed nuts about 9 feet off the ground (this guy was a nut meister) and just kep on going. the clmiber had placed a lot of em cause it was a new route and well, the crack just was made for nuts.
So everything was fine and the buddy was cleanign his way up the crack, saying things like, " man your nutcraft is beautiful, such mastery, very nice man.", and more of the same. Then he got to one that wouldn't just lift out. Well the silly nut not only wouldn't lift, it had been hung on, but the cleaner didn't know that yet. A moment of silence passed. THen, the bitching commenced. "Man, why do people have to set nuts so HARD? This crack is perfect, no way that nut would come out. You don't have to set em in a crack like this. I can;t beleive it..." and on and on.
Finally we told him about hanging on the nut. He didn't miss a beat. didn;t pphase him at all. That nut had been set too damned hard and we were going to hear about it. Once you get a guy on that stuff about setting nuts, you can't stop em LOL.
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piton
Jan 30, 2005, 10:02 PM
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In reply to: When I do clip directly I tend to set the hell out of the nut (nut tool required for extraction
i do this on all nut placements.
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irockclimbtoo
Jan 30, 2005, 11:39 PM
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ab
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crankingclimber
Jan 30, 2005, 11:58 PM
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Not sure if I've seen the Masters video you're talking about, (I've only seen the last two), but possbily, since the guys on those videos are usually doing something hardcore, they were climbing an R rated route, where the 6 inches or so that they save by not placing a draw on the route was worth it in an effort to keep themselves off the deck or off a ledge. Usually however it's a bad idea - real bad. The nut can be pulled out easier, and there's a lot more drag. I have done it in incredibly specific circumstances to cams a couple of times - would be very leery of doing it with a nut though, only a very specific type of placement that would work for. Just some thoughts...
Will
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