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akleeka
Oct 5, 2012, 9:25 PM
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hi Do the normal force multiplication rules apply exactly the same to anchors built vertically in a crack, as they do to the more commonly built ground anchors e.g. where your pieces are set more top to bottom vs left to right? Normally I don't have/like to do this but sometimes I have to build the entire anchor in a crack. It's nice to space the pieces to some extent so that if one pulls it won't hit a piece below and pull it, though the piece more likely would be coming out of the crack not down. Anyway I always wonder in this case what's going on with the force multiplication if I spread the pieces too far out, do I still need to avoid the > 45/60 degree V angle scenario?. To my mind the answer is yes, but I've been told otherwise. One other question on V angle, any good tips on what to do in scenarios where you want to incorporate a really bomber placement (say off to the side) with some more sketchy placements (say directly at top of climb), but using the bomber placement is going to put the V angle way out there? The only solution I've found to this is to extend out the master point as far as I can, which lessens the angle, but unless it's a top rope setup or some such you usually can't extend it that much. I don't like to rely on just the bomber placement alone either, then there's no redundancy. thanks
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rocknice2
Oct 5, 2012, 9:39 PM
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Make your anchor and pull the power point toward the direction of load. If there is an angle formed them the formula applies.
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billl7
Oct 5, 2012, 10:41 PM
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rocknice2 wrote: Make your anchor and pull the power point toward the direction of load. If there is an angle formed them the formula applies. He's right. So if the crack is straight up on a vertical wall and the load is down, the angles will stay negligible and 'spacing' of pro is not very important. As for the bomber piece out to the side: Are you belaying from below so the rope runs the length of the route up to the anchor? Is the slack introduced when the anchor fails onto the bomber piece pretty small compared to the total rope run? I think in this case I'd build my anchor out where there are bomber pieces and place a piece closer to the top of the climb as a redirect.
(This post was edited by billl7 on Oct 5, 2012, 10:44 PM)
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jeepnphreak
Oct 7, 2012, 3:26 PM
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One thing I do when bulding a gear anchor in a verticle/near verticle crack, is try to stack the pro largest lower down and the smaller pro higher. My thinking here is that because the arms of the anchor are not equal; the lower (closer to the master point) the more force that lower piece of pro is going to be subjected to. So I want the largest bomber piece lower where the foreces will be greatest.
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rocknice2
Oct 7, 2012, 3:51 PM
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jeepnphreak wrote: One thing I do when bulding a gear anchor in a verticle/near verticle crack, is try to stack the pro largest lower down and the smaller pro higher. My thinking here is that because the arms of the anchor are not equal; the lower (closer to the master point) the more force that lower piece of pro is going to be subjected to. So I want the largest bomber piece lower where the foreces will be greatest. Seriously!!! I'm happy to get 3 bomber pieces from the gear I have left on my rack after a pitch.
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blueeyedclimber
Oct 7, 2012, 5:15 PM
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akleeka wrote: hi Do the normal force multiplication rules apply exactly the same to anchors built vertically in a crack, as they do to the more commonly built ground anchors e.g. where your pieces are set more top to bottom vs left to right? Normally I don't have/like to do this but sometimes I have to build the entire anchor in a crack. It's nice to space the pieces to some extent so that if one pulls it won't hit a piece below and pull it, though the piece more likely would be coming out of the crack not down. Anyway I always wonder in this case what's going on with the force multiplication if I spread the pieces too far out, do I still need to avoid the > 45/60 degree V angle scenario?. To my mind the answer is yes, but I've been told otherwise. Yes, any angle in anchors, no matter what orientation your pieces are in, will follow the force multiplication rules. BUT, in a vertical crack, with your pieces above you, the direction of pull will be straight down, negating any increase in angle from your pieces being spread apart. The exception to this is if your pull is outward at all. Also, listen to what jeepnfreak says about the shortest leg producing more force on the piece.
In reply to: One other question on V angle, any good tips on what to do in scenarios where you want to incorporate a really bomber placement (say off to the side) with some more sketchy placements (say directly at top of climb), but using the bomber placement is going to put the V angle way out there? My first question would be why would you set up an anchor with sketchy placements, especially if your talking about a top rope anchor. You have the luxury of finding something better.
In reply to: The only solution I've found to this is to extend out the master point as far as I can, which lessens the angle, but unless it's a top rope setup or some such you usually can't extend it that much. I don't like to rely on just the bomber placement alone either, then there's no redundancy. thanks This is very situational and depends on a lot of things, including how bomber that piece is, how sketchy the other pieces are, how far off to the side it is, if you can get a solid stance, etc. Josh
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jeepnphreak
Oct 8, 2012, 3:50 PM
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rocknice2 wrote: jeepnphreak wrote: One thing I do when bulding a gear anchor in a verticle/near verticle crack, is try to stack the pro largest lower down and the smaller pro higher. My thinking here is that because the arms of the anchor are not equal; the lower (closer to the master point) the more force that lower piece of pro is going to be subjected to. So I want the largest bomber piece lower where the foreces will be greatest. Seriously!!! I'm happy to get 3 bomber pieces from the gear I have left on my rack after a pitch. Yeah I'm serious, get 1 bomber piece in, use that as the lower piece, cloest to your master point. then get two pieces in higher. If you can't get in at least 1 solid piece of pro in you need to go back and re-evaluate your anchor buliding skills. It is really not to hard to bulid your anchor around your most solid piece of gear. I will agree that 3 bomber pieces does not always happen, its nice when it does.
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redlude97
Oct 8, 2012, 4:18 PM
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jeepnphreak wrote: rocknice2 wrote: jeepnphreak wrote: One thing I do when bulding a gear anchor in a verticle/near verticle crack, is try to stack the pro largest lower down and the smaller pro higher. My thinking here is that because the arms of the anchor are not equal; the lower (closer to the master point) the more force that lower piece of pro is going to be subjected to. So I want the largest bomber piece lower where the foreces will be greatest. Seriously!!! I'm happy to get 3 bomber pieces from the gear I have left on my rack after a pitch. Yeah I'm serious, get 1 bomber piece in, use that as the lower piece, cloest to your master point. then get two pieces in higher. If you can't get in at least 1 solid piece of pro in you need to go back and re-evaluate your anchor buliding skills. It is really not to hard to bulid your anchor around your most solid piece of gear. I will agree that 3 bomber pieces does not always happen, its nice when it does. So you would ignore 2 better placements below your "bomber" piece in lieu of two worse placements above the "bomber" piece? If you want the majority of the force to be applied to the "bomber" piece couldn't you just clove that leg shorter so it takes almost all the force?
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moose_droppings
Oct 8, 2012, 4:44 PM
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jeepnphreak wrote: My thinking here is that because the arms of the anchor are not equal; the lower (closer to the master point) the more force that lower piece of pro is going to be subjected to You know that's only true if all the legs of the anchor are equally tensioned. If using clove hitches you could adjust the bomber piece to have more tension on it. You could spend a lot of time fussing with it, or you could just tie your pieces together the best you can and rely on the redundancy of three pieces. Edit. Redlude beat me to the point while I was interrupted on the phone.
(This post was edited by moose_droppings on Oct 8, 2012, 4:49 PM)
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rocknice2
Oct 8, 2012, 5:36 PM
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I'm very happy with my anchor building skills. Thank you for the concern though.
(This post was edited by rocknice2 on Oct 8, 2012, 5:51 PM)
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j_ung
Oct 8, 2012, 8:44 PM
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redlude97 wrote: jeepnphreak wrote: rocknice2 wrote: jeepnphreak wrote: One thing I do when bulding a gear anchor in a verticle/near verticle crack, is try to stack the pro largest lower down and the smaller pro higher. My thinking here is that because the arms of the anchor are not equal; the lower (closer to the master point) the more force that lower piece of pro is going to be subjected to. So I want the largest bomber piece lower where the foreces will be greatest. Seriously!!! I'm happy to get 3 bomber pieces from the gear I have left on my rack after a pitch. Yeah I'm serious, get 1 bomber piece in, use that as the lower piece, cloest to your master point. then get two pieces in higher. If you can't get in at least 1 solid piece of pro in you need to go back and re-evaluate your anchor buliding skills. It is really not to hard to bulid your anchor around your most solid piece of gear. I will agree that 3 bomber pieces does not always happen, its nice when it does. So you would ignore 2 better placements below your "bomber" piece in lieu of two worse placements above the "bomber" piece? If you want the majority of the force to be applied to the "bomber" piece couldn't you just clove that leg shorter so it takes almost all the force? That's not what he said.
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jeepnphreak
Oct 9, 2012, 1:18 AM
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redlude97 wrote: jeepnphreak wrote: rocknice2 wrote: jeepnphreak wrote: One thing I do when bulding a gear anchor in a verticle/near verticle crack, is try to stack the pro largest lower down and the smaller pro higher. My thinking here is that because the arms of the anchor are not equal; the lower (closer to the master point) the more force that lower piece of pro is going to be subjected to. So I want the largest bomber piece lower where the foreces will be greatest. Seriously!!! I'm happy to get 3 bomber pieces from the gear I have left on my rack after a pitch. Yeah I'm serious, get 1 bomber piece in, use that as the lower piece, cloest to your master point. then get two pieces in higher. If you can't get in at least 1 solid piece of pro in you need to go back and re-evaluate your anchor buliding skills. It is really not to hard to bulid your anchor around your most solid piece of gear. I will agree that 3 bomber pieces does not always happen, its nice when it does. So you would ignore 2 better placements below your "bomber" piece in lieu of two worse placements above the "bomber" piece? If you want the majority of the force to be applied to the "bomber" piece couldn't you just clove that leg shorter so it takes almost all the force? No thats not what I'm saying. Because when you build an anchor in a vertical fashion, from the master point, the piece of pro on the shortest arm of the rope/cordlette ect, has more force on it. Because the rope stretch is a percentage the shorter arm will have to hold a greater force during a fall. The piece of gear furthest from the master point has more rope so a touch less force will be on that upper piece of gear because more rope will stretch a bit more. So I try to build the anchor when the most bomber piece is the lowest and then “equalize” as best as you can. Granted this is a best case scenario. But I usually can get two out of three placements solid and frequently the third piece of pro is good too. I just like to try and get the larger piece on the bottom.
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redlude97
Oct 9, 2012, 3:30 AM
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jeepnphreak wrote: redlude97 wrote: jeepnphreak wrote: rocknice2 wrote: jeepnphreak wrote: One thing I do when bulding a gear anchor in a verticle/near verticle crack, is try to stack the pro largest lower down and the smaller pro higher. My thinking here is that because the arms of the anchor are not equal; the lower (closer to the master point) the more force that lower piece of pro is going to be subjected to. So I want the largest bomber piece lower where the foreces will be greatest. Seriously!!! I'm happy to get 3 bomber pieces from the gear I have left on my rack after a pitch. Yeah I'm serious, get 1 bomber piece in, use that as the lower piece, cloest to your master point. then get two pieces in higher. If you can't get in at least 1 solid piece of pro in you need to go back and re-evaluate your anchor buliding skills. It is really not to hard to bulid your anchor around your most solid piece of gear. I will agree that 3 bomber pieces does not always happen, its nice when it does. So you would ignore 2 better placements below your "bomber" piece in lieu of two worse placements above the "bomber" piece? If you want the majority of the force to be applied to the "bomber" piece couldn't you just clove that leg shorter so it takes almost all the force? No thats not what I'm saying. Because when you build an anchor in a vertical fashion, from the master point, the piece of pro on the shortest arm of the rope/cordlette ect, has more force on it. Because the rope stretch is a percentage the shorter arm will have to hold a greater force during a fall. The piece of gear furthest from the master point has more rope so a touch less force will be on that upper piece of gear because more rope will stretch a bit more. So I try to build the anchor when the most bomber piece is the lowest and then “equalize” as best as you can. Granted this is a best case scenario. But I usually can get two out of three placements solid and frequently the third piece of pro is good too. I just like to try and get the larger piece on the bottom. Like I mentioned above if your goal is to shift the force to your best piece, than you can clove that leg shorter so it has a higher proportion of the force. No need to make the force the anchor to be oriented with the bomber piece on the bottom to get your desired force distribution.
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bearbreeder
Oct 9, 2012, 5:11 AM
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usually the nature of the crack and the gear you have left at the end of the pitch dictates the placements ... if one is so concerned there are various ways of insuring that a certain piece will see most of the load ... not necessarily the lowest
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hugepedro
Oct 9, 2012, 5:28 AM
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jeepnphreak wrote: One thing I do when bulding a gear anchor in a verticle/near verticle crack, is try to stack the pro largest lower down and the smaller pro higher. My thinking here is that because the arms of the anchor are not equal; the lower (closer to the master point) the more force that lower piece of pro is going to be subjected to. So I want the largest bomber piece lower where the foreces will be greatest. That is about the silliest thing I've ever heard of.
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blueeyedclimber
Oct 9, 2012, 12:28 PM
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hugepedro wrote: jeepnphreak wrote: One thing I do when bulding a gear anchor in a verticle/near verticle crack, is try to stack the pro largest lower down and the smaller pro higher. My thinking here is that because the arms of the anchor are not equal; the lower (closer to the master point) the more force that lower piece of pro is going to be subjected to. So I want the largest bomber piece lower where the foreces will be greatest. That is about the silliest thing I've ever heard of. Pedro, you've been around long enough to realize there are far sillier things that have been said. I think his philosophy is flawed because its entirely situational, but his point about the shortest leg in a cordellete/ power point style anchor being the one that sees the most force, is an important thing to know. Josh
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hugepedro
Oct 9, 2012, 2:34 PM
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blueeyedclimber wrote: hugepedro wrote: jeepnphreak wrote: One thing I do when bulding a gear anchor in a verticle/near verticle crack, is try to stack the pro largest lower down and the smaller pro higher. My thinking here is that because the arms of the anchor are not equal; the lower (closer to the master point) the more force that lower piece of pro is going to be subjected to. So I want the largest bomber piece lower where the foreces will be greatest. That is about the silliest thing I've ever heard of. Pedro, you've been around long enough to realize there are far sillier things that have been said. I think his philosophy is flawed because its entirely situational, but his point about the shortest leg in a cordellete/ power point style anchor being the one that sees the most force, is an important thing to know. Josh Yeah, prolly been sillier stuff said, but in the context of anchor building this is awfully silly. If you're actually worried about this you're doing it wrong.
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cracklover
Oct 9, 2012, 6:07 PM
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hugepedro wrote: blueeyedclimber wrote: hugepedro wrote: jeepnphreak wrote: One thing I do when bulding a gear anchor in a verticle/near verticle crack, is try to stack the pro largest lower down and the smaller pro higher. My thinking here is that because the arms of the anchor are not equal; the lower (closer to the master point) the more force that lower piece of pro is going to be subjected to. So I want the largest bomber piece lower where the foreces will be greatest. That is about the silliest thing I've ever heard of. Pedro, you've been around long enough to realize there are far sillier things that have been said. I think his philosophy is flawed because its entirely situational, but his point about the shortest leg in a cordellete/ power point style anchor being the one that sees the most force, is an important thing to know. Josh Yeah, prolly been sillier stuff said, but in the context of anchor building this is awfully silly. If you're actually worried about this you're doing it wrong. The problem with the advice is not that it addresses a problem unworthy of consideration, but that it's a completely impractical solution to that problem in the real world. GO
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hugepedro
Oct 9, 2012, 6:59 PM
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cracklover wrote: hugepedro wrote: blueeyedclimber wrote: hugepedro wrote: jeepnphreak wrote: One thing I do when bulding a gear anchor in a verticle/near verticle crack, is try to stack the pro largest lower down and the smaller pro higher. My thinking here is that because the arms of the anchor are not equal; the lower (closer to the master point) the more force that lower piece of pro is going to be subjected to. So I want the largest bomber piece lower where the foreces will be greatest. That is about the silliest thing I've ever heard of. Pedro, you've been around long enough to realize there are far sillier things that have been said. I think his philosophy is flawed because its entirely situational, but his point about the shortest leg in a cordellete/ power point style anchor being the one that sees the most force, is an important thing to know. Josh Yeah, prolly been sillier stuff said, but in the context of anchor building this is awfully silly. If you're actually worried about this you're doing it wrong. The problem with the advice is not that it addresses a problem unworthy of consideration, but that it's a completely impractical solution to that problem in the real world. GO That's a better answer than me just calling it silly. It is, however, still silly.
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cracklover
Oct 9, 2012, 7:42 PM
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hugepedro wrote: cracklover wrote: hugepedro wrote: blueeyedclimber wrote: hugepedro wrote: jeepnphreak wrote: One thing I do when bulding a gear anchor in a verticle/near verticle crack, is try to stack the pro largest lower down and the smaller pro higher. My thinking here is that because the arms of the anchor are not equal; the lower (closer to the master point) the more force that lower piece of pro is going to be subjected to. So I want the largest bomber piece lower where the foreces will be greatest. That is about the silliest thing I've ever heard of. Pedro, you've been around long enough to realize there are far sillier things that have been said. I think his philosophy is flawed because its entirely situational, but his point about the shortest leg in a cordellete/ power point style anchor being the one that sees the most force, is an important thing to know. Josh Yeah, prolly been sillier stuff said, but in the context of anchor building this is awfully silly. If you're actually worried about this you're doing it wrong. The problem with the advice is not that it addresses a problem unworthy of consideration, but that it's a completely impractical solution to that problem in the real world. GO That's a better answer than me just calling it silly. It is, however, still silly. LOL, yep! GO
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curt
Oct 9, 2012, 11:39 PM
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blueeyedclimber wrote: hugepedro wrote: jeepnphreak wrote: One thing I do when bulding a gear anchor in a verticle/near verticle crack, is try to stack the pro largest lower down and the smaller pro higher. My thinking here is that because the arms of the anchor are not equal; the lower (closer to the master point) the more force that lower piece of pro is going to be subjected to. So I want the largest bomber piece lower where the foreces will be greatest. That is about the silliest thing I've ever heard of. Pedro, you've been around long enough to realize there are far sillier things that have been said. I think his philosophy is flawed because its entirely situational, but his point about the shortest leg in a cordellete/ power point style anchor being the one that sees the most force, is an important thing to know. Josh The idea that the shortest leg in an anchor system will probably have the highest tension when loaded is an interesting thing to know--in a Trivial Pursuit sort of way. Important though? Not really. Curt
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blueeyedclimber
Oct 10, 2012, 12:39 AM
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cracklover wrote: hugepedro wrote: blueeyedclimber wrote: hugepedro wrote: jeepnphreak wrote: One thing I do when bulding a gear anchor in a verticle/near verticle crack, is try to stack the pro largest lower down and the smaller pro higher. My thinking here is that because the arms of the anchor are not equal; the lower (closer to the master point) the more force that lower piece of pro is going to be subjected to. So I want the largest bomber piece lower where the foreces will be greatest. That is about the silliest thing I've ever heard of. Pedro, you've been around long enough to realize there are far sillier things that have been said. I think his philosophy is flawed because its entirely situational, but his point about the shortest leg in a cordellete/ power point style anchor being the one that sees the most force, is an important thing to know. Josh Yeah, prolly been sillier stuff said, but in the context of anchor building this is awfully silly. If you're actually worried about this you're doing it wrong. The problem with the advice is not that it addresses a problem unworthy of consideration, but that it's a completely impractical solution to that problem in the real world. GO I agree. Better worded than mine, as well.
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billcoe_
Oct 11, 2012, 3:14 AM
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curt wrote: The idea that the shortest leg in an anchor system will probably have the highest tension when loaded is an interesting thing to know--in a Trivial Pursuit sort of way. Important though? Not really. Curt Exactly. Usually there is a vertical crack, and it can have 3 pieces in it. Got me, I try and stuff a cam in first (lowest/closest to me) so that I can stop worrying about an upwards. I look for a placement that will allows it to rotate and stay in if my leader takes a big fall onto a piece above so that I am lifted upwards. This is because I often want the cams for the leaders next pitch, and grab wired nuts for the belay. The other thing is a quick exam of the rack (given that you've stuffed pieces in below you need to remember what they were) . If there are 3 #1 cams but a single #2, I'll try and use one of the #1s for the same reason. In regards to the V angle question, you aren't going to appreciably make it flat enough to make a craps worth of difference. So use the best pieces you can find and worry about getting good solid placements in there IMO.
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