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mgoodro
Jun 3, 2005, 10:00 PM
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This thread has been so enlightening (and entertaining) that I'm inspired to take a position.
I am 100% opposed to altering the rock in any way. If something needs to be done, move the bolt. Altering the natural features of a climb is very bad karma. (If you're willing to take a hammer to it, why stop there? Why not drill or glue holds?) Yes, that logic can be applied to bolting in general, but lets keep this thread off the bolting subject. I'd like to see some additional thoughtful opinions on a solution to this potentially dangerous bolt placement, including whether any alteration is warranted.
It's amazing, with all the posts that devolve into bashing and flame wars that this one keeps returning to legitimate discussion. Thanks to the OP for the post, and for keeping it current.
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toejam
Jun 3, 2005, 10:25 PM
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Jbell and bdeaug, thanks for posting and providing such ample documentation. Definitely have given me something think about while sport cragging.
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caughtinside
Jun 3, 2005, 10:29 PM
Post #178 of 188
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In reply to: I am 100% opposed to altering the rock in any way. If something needs to be done, move the bolt. Altering the natural features of a climb is very bad karma. (If you're willing to take a hammer to it, why stop there? Why not drill or glue holds?) Yes, that logic can be applied to bolting in general, but lets keep this thread off the bolting subject. I'd like to see some additional thoughtful opinions on a solution to this potentially dangerous bolt placement, including whether any alteration is warranted.
Gonna have to disagree. If done properly, rounding over that edge does less damage to the rock than removing that bolt and placing a new one. Less visual impact as well.
However, that is a really poor place for a bolt, I'm not sure a draw will ever hang well there. Moving the bolt might be the only real option.
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dingus
Jun 4, 2005, 12:48 AM
Post #179 of 188
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Sounds like a known route. How about notifying the FA party of what happened and have them deal with it? After all, they created the potential for this mishap?
DMT
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newton
Jun 4, 2005, 1:48 AM
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Just felt I had to address some of majid's comments here. I would really like to see more climbers who are able to correctly analyze their protection systems (funny, most folks who free-solo and boulder seem to understand theirs perfectly. hmmm.....). Anyway I guess I'll just go through this point by point.
In reply to: Biner works as pulley in this case causing a 2-1 mechanical advantage on that webbing In reply to: Using a biner in between webbing creates a mechanical advantage meaning the force or the weight of the object is divided equally to both sides therefore you can pull the object easier
Actually, there is no pulley in the scenario. Basic way mechanical advantage works- pull farther and less hard. If I rig a 2:1 system, I pull twice the rope and half the weight of the original haul. If the rope goes is fixed on one end, goes down to the load pulley (can be a biner) and back up to me, I have my 2:1 system. I pull in the rope 2m, but the bag only comes up one meter, and I only pull half the weight.
But,...if I'm pulling down through a top anchor (same situation as sides of the qd through the biner), I pull down 2m, and the rope goes up 2m. No mechanical advantage. Just a change of direction. I still pull full weight plus friction.
In reply to: ...webbing is cut from sewn( The weakest part of the sling) most knots reduces the strength of the webbing or rope by 30% . In reply to: Any time you take a soft gear such as webbing, rope, sling etc and you bend a loop, that loop itself becomes the weakest part of that system or webbing etc. In reply to: ....if your webbing is rated at 2000 lbs with a loop now you have 4000 lbs strength in that system without the sewn or knot, once you have any sewn or knot, the strength reduces by some # near 30% +-.
I'll just go over the whole deal on this one. Some of these points were pointed out by others. Majid, you are correct about webbing or rope bending around a biner. It is weaker than the portions of the webbing that are loaded straight. Also knots do significantly reduce strength. However, from everything I've heard (yes, I do trust those guys at the labs where they break this stuff for a living) the stitching is the strongest part of a sewn runner or draw.
I'm not sure exactly what you meant by the 2k lbs 4k lbs comment, but I will support what I think you are saying. When a runner or qd is rated at some force (weight), the actual strength of the material that made it is roughly half that. You make a 22kN runner from about 11 kN webbing. The load is divided equally between the sides. Not really of much importance in most situations- just realize if you somehow use only one strand of the runner, the strength is half of what your loop was.
On a tangent here, but- when you are holding on toprope, your anchor does see twice the load you are holding. According to Newton's second law (Force=mass * acceleration), for the masses not to accelerate (start moving) , the sum of all forces must be zero. So the weight on each end of the rope balances the other side and it does not move. But, both sides of the rope pull down on the anchor, so for it to not move, the reactionary force of the anchor must be twice the load on you are holding. This is a static simplification that can be loosely applied to a much more complicated dynamic situation (i.e. a fall).
Our load on a draw is not doubled though, because you have the opposite situation on the bottom of the draw. The load is split at the bottom, each side of the webbing carries twice the load, then that whole load goes to the top biner.
In reply to: I still think that sling got snapped by tension not from a sharp edge.
Just a little experience from someone who's actually done some materials testing... in my experience, a material like this would show a lot more deformation if it failed from excessive load (plus our lucky op would have some serious issues getting his hips reattached to his torso).
Newt
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jbell2355
Jun 4, 2005, 2:28 PM
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Dingus-I have contacted the FA and discussed the problem with him. He was planning to check it out last weekend, but I haven't heard from him yet. His initial indication was that he would try removing the sharp edge with a hammer, but I don't know what, if anything, he has done yet. This route doesn't get led all that often and I think all the locals that do lead it now know about the problem. I am concerned about non-locals getting on it and getting injured though.
I don't want to get into the debate about moving the bolt versus altering the rock...I don't really have a strong opinion one way or the other
Alpnclmbr1-the pictures show that the cut in the draw lines up perfectly with the edge. I don't know what the hell you're talking about.
To those of you who have thanked me for starting this thread: you're welcome. I'm glad you've learned from it. That was my only objective here.
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angry
Jun 4, 2005, 3:02 PM
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Majid Sabet physics. I neat little scary world.
Oh well, I'm going to go nail my dick to a burning building.
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dingus
Jun 4, 2005, 5:09 PM
Post #183 of 188
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In reply to: Dingus-I have contacted the FA and discussed the problem with him. He was planning to check it out last weekend, but I haven't heard from him yet. His initial indication was that he would try removing the sharp edge with a hammer, but I don't know what, if anything, he has done yet.
Well there ya go. Let the person who created this placement fix it... its easy enough to fix with either remedy (blunt it or move it).
DMT
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e_free
Jun 6, 2005, 12:16 AM
Post #184 of 188
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Just wanted to say thank you to jbell & belayer for their posts & pictures. glad you are okay: as Glen Berteau says, "If its not over, its only just begun!" ;)
and thanks again for looking out for the rest of us by sharing your story.
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omegaprime
Jun 6, 2005, 1:23 AM
Post #185 of 188
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Thanks to the OP for enlightening us with this thread, its something that I have not considered as a possible threat to my safety when climbing. I'll have to start scrutinizing my protections more after knowing what happened to you.
Cheers.
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treez
May 1, 2006, 9:46 PM
Post #186 of 188
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Registered: Aug 11, 2004
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So what action was taken regarding this bolt? Relocation? Blunting? Chain?
Not that I'm headed over there, just curious due to this scenario repeating itself.
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dudemanbu
May 1, 2006, 11:09 PM
Post #187 of 188
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Registered: Jun 3, 2005
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always wear your helmet.
:P
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treez
May 1, 2006, 11:50 PM
Post #188 of 188
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In reply to: always wear your helmet. :P
Thanks for the bump, dude, but major virtual penalty slack for saying the damn H-word.
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