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absinthe52
Apr 21, 2010, 10:00 PM
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I want to use a sliding X since I am without a cordellet for right now. As there is no Top-Shelf for the redirect, whats the best method to set this up so I can belay off my harness? Also, I'm usuing a B-52. If I want a direct belay, can I just clip another locker in to the belay anchor? Thanks
Oh yes, question refers to a two bolt achor system, not trad. Instead of messing with the anchor system for a redirect, can I just clip a quickdraw into either bolt and use that?
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johnwesely
Apr 21, 2010, 10:18 PM
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absinthe52 wrote: I want to use a sliding X since I am without a cordellet for right now. As there is no Top-Shelf for the redirect, whats the best method to set this up so I can belay off my harness? Also, I'm usuing a B-52. If I want a direct belay, can I just clip another locker in to the belay anchor? Thanks
Make sure that your extra locker goes through the same strands as the first.
In reply to: Oh yes, question refers to a two bolt achor system, not trad. Instead of messing with the anchor system for a redirect, can I just clip a quickdraw into either bolt and use that?
I wouldn't mind doing that, but I am sure somebody would have an objection.
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dugl33
Apr 21, 2010, 10:27 PM
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absinthe52 wrote: I want to use a sliding X since I am without a cordellet for right now. As there is no Top-Shelf for the redirect, whats the best method to set this up so I can belay off my harness? Also, I'm usuing a B-52. If I want a direct belay, can I just clip another locker in to the belay anchor? Thanks Oh yes, question refers to a two bolt achor system, not trad. Instead of messing with the anchor system for a redirect, can I just clip a quickdraw into either bolt and use that?
This may not be the textbook answer, but if the bolts look bomber, I'll set up the sliding x off a locker to each bolt hanger, and clip myself to it with another sling girth hitched to the harness proper and a locker to the sliding x. I will then back myself up with the rope to one of the bolts, say the right one, and tie a clove hitch directly to the locker. I leave the rope a bit slack. Next I'll clip a draw to the left hand locker and redirect the belay through this.
Ok. So, its not perfectly equalized. If the second falls, twice his or her weight is on that one bolt. But, if the bolt's are bomber, this doesn't bother me -- and its fairly organized and convenient.
If the bolts looks sketch, I'll either choose not to redirect the belay, or I'll tie in with the rope to the sliding x with a bit more slack to hang a bit lower, and redirect the belay off the sliding x as well.
If the bolts look really sketch I'll try to get a stance that allows me to support myself and the second without weighting the bolts at all, which may not always be possible, and at best, is uncomfortable.
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patto
Apr 22, 2010, 12:09 AM
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dugl33 wrote: Next I'll clip a draw to the left hand locker and redirect the belay through this.
What the hell?
Surely you are building an anchor primarily for the belay and not for yourself. Why would you put the belay on a single bolt!?
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hafilax
Apr 22, 2010, 12:18 AM
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absinthe52 wrote: I want to use a sliding X since I am without a cordellet for right now. As there is no Top-Shelf for the redirect, whats the best method to set this up so I can belay off my harness? Also, I'm usuing a B-52. If I want a direct belay, can I just clip another locker in to the belay anchor? Thanks Oh yes, question refers to a two bolt achor system, not trad. Instead of messing with the anchor system for a redirect, can I just clip a quickdraw into either bolt and use that?
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johnwesely
Apr 22, 2010, 12:22 AM
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patto wrote: dugl33 wrote: Next I'll clip a draw to the left hand locker and redirect the belay through this. What the hell? Surely you are building an anchor primarily for the belay and not for yourself. Why would you put the belay on a single bolt!?
Because it is still off two bolts. If that bolt were to somehow explode, the climber would still be supported by the other bolt.
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dugl33
Apr 22, 2010, 12:41 AM
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patto wrote: dugl33 wrote: Next I'll clip a draw to the left hand locker and redirect the belay through this. What the hell? Surely you are building an anchor primarily for the belay and not for yourself. Why would you put the belay on a single bolt!?
simmer down... simmer down...
First off, the belay is not on a single bolt, its on my waist. I'm only redirecting the rope through a draw on a single bolt. If you read what I posted, the presumption is the bolts are bomber, and a hang from a seconding climber is not going to generate a huge force and even if that bolt were to mysteriously fail from a few hundred pounds of load, I am still attached to the other bolt, and the second is still on belay on my waist. And since I backed up with the rope I don't even have much extension as the magic x slides out.
As implied in my original post, I would not do this on a pair of rusted out manky 1/4" split shaft bolts spinning about in cratered out sandstone choss. Picture 3/8" or 1/2" bolts with beefy hangers in granite -- breathing any easier?
For me its nice to have the redirect off to one side. If I were to belay in guide mode it would be straight onto the magic x, power point, or the V created by two slings.
Lots of ways to skin a kitten, but it takes some modicum of circumstantial judgment.
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blueeyedclimber
Apr 22, 2010, 12:41 PM
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absinthe52 wrote: I want to use a sliding X since I am without a cordellet for right now. As there is no Top-Shelf for the redirect, whats the best method to set this up so I can belay off my harness? Also, I'm usuing a B-52. If I want a direct belay, can I just clip another locker in to the belay anchor? Thanks Oh yes, question refers to a two bolt achor system, not trad. Instead of messing with the anchor system for a redirect, can I just clip a quickdraw into either bolt and use that?
Yes.
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cfnubbler
Apr 22, 2010, 1:18 PM
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Since nobody else has asked it, I'll pose the obvious question: why would you want to redirect your belay when there are so many better alternatives? I'm hard pressed to think of a single set of circumstances in which a redirect is the best choice.
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dingus
Apr 22, 2010, 2:26 PM
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On two good bolts I wouldn't bother with a sliding X, a cordalette or any other gimmicky belay knotting arrangement.
Two draws, knot knot, clip clip, DONE.
Redirect with a biner added to one of the draws, if necessary. I rarely redirect.
KISS.
DMT
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cfnubbler
Apr 22, 2010, 2:35 PM
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dingus wrote: On two good bolts I wouldn't bother with a sliding X, a cordalette or any other gimmicky belay knotting arrangement. Two draws, knot knot, clip clip, DONE. Redirect with a biner added to one of the draws, if necessary. I rarely redirect. KISS. DMT
KISS for sure. My preferred set up for 2 bomber bolts when I'm confident the direction of pull won't change dramatically is a shoulder length sling, one end clipped to each bolt, knotted ~ in the middle to create two independent loops. My clip in locker / clove goes through each loop just above the knot. A belay locker for a Reverso style device or munter can go the same place, be stacked on my clip-in locker, ect. All I need for this set up is a single runner and two carabiners (plus a locker for me, and another 1-2 lockers depending on my belay method).
As I mentioned, I can't think of any instance in which I'd be willing to use one when a redirect is preferrable to a direct belay.
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antiqued
Apr 22, 2010, 5:12 PM
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cfnubbler wrote: As I mentioned, I can't think of any instance in which I'd be willing to use one when a redirect is preferrable to a direct belay.
Just some suggestions:
Saves time - you are already set up to belay the leader and they are already clipped to the first piece to avoid a factor 2. They just climb through.
If you as heavy than your second, and a little help/haul might be needed, then you are already set up to use your body weight. Stand up, suck in, squat down.
If the anchor points are too high, out of reach of a comfortable ledge (instead of extending the direct belay, and having it flop, or enduring a hanging belay).
And a question: How can you do this with a shoulder length sling? A foot between the bolts, and 8" for a knot leaves no slack at all. Don't you need a double?
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jt512
Apr 22, 2010, 5:31 PM
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dugl33 wrote: absinthe52 wrote: I want to use a sliding X since I am without a cordellet for right now. As there is no Top-Shelf for the redirect, whats the best method to set this up so I can belay off my harness? Also, I'm usuing a B-52. If I want a direct belay, can I just clip another locker in to the belay anchor? Thanks Oh yes, question refers to a two bolt achor system, not trad. Instead of messing with the anchor system for a redirect, can I just clip a quickdraw into either bolt and use that? This may not be the textbook answer, but if the bolts look bomber, I'll set up the sliding x off a locker to each bolt hanger, and clip myself to it with another sling girth hitched to the harness proper and a locker to the sliding x. I will then back myself up with the rope to one of the bolts, say the right one, and tie a clove hitch directly to the locker. I leave the rope a bit slack. Next I'll clip a draw to the left hand locker and redirect the belay through this. Ok. So, its not perfectly equalized. If the second falls, twice his or her weight is on that one bolt.
This common misconception is false. A clean toprope fall will weight the anchor by at least 3 times the climber's body weight. That assumes there is absolutely no slack in the rope. With slack, the impact force can be much higher.
Consider what might be the worst case scenario. Say the climber fell making the last move to the anchor, and impacted the rope before the belayer could take up any of the slack, producing, say, a 2-foot fall onto three feet of rope—a factor-0.67 fall. Then the impact force on the anchor would be on the order of 12 times the climber's body weight. With a 200-lb climber, the anchor would feel about 2600 lb of force (11.5 kN). The bolt you think is bomber better had be.
Jay
(This post was edited by jt512 on Apr 22, 2010, 5:33 PM)
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cfnubbler
Apr 22, 2010, 5:36 PM
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Hello Antiqued,
In response to your comments:
Saves time: Not really, as I can easily have the new leader on belay and ready to move out long before s/he is done re-racking when using a reverso style device.
Help / Haul: The quickest way to a 3:1 (theoretical advantage) raise is by using a reverso-style device. If less assistance is needed, I can generally accomplish the task with agressive tension.
Out of reach anchor: There are lots of ways to arrange direct belays with anchor extensions in such situations. In general, provided I can easily get back to the anchor if necessary, I still prefer to have the device up near it because this avoids my second having to climb above an extended device on his/her way up to the anchor to clip in. True, this can also be avoided by a redirect, but I much prefer to not be belaying directly off my harness, which the redirect requires. I also dislike the cluster of strands of rope running everywhere created by my own extended clip-in (which is likely to involve 2 strands if I've muntered myself down to a stance well below the anchor), the strand from my device to the redirect point at the anchor, and then the strand going back down to the second. Too complicated for my tastes when there are easier, faster, and cleaner options.
Length of runner: I carry two 30" or so slings that work well enough for most bolted stances. Sorry to have been unclear...you're certainly correct that a typical over the shoulder runner is too short in most cases.
There are no perfect solutions, only tools to be applied were appropriate. I feel that since anything useful accomplished by a redirect can be accomplished as easily in other ways, I see no reason to double the potential load on my anchors when I don't need to. Of course a modern bolted anchor is more than strong enough for such a load, but I still prefer to avoid it. YMMV.
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dugl33
Apr 22, 2010, 6:08 PM
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jt512 wrote: dugl33 wrote: absinthe52 wrote: I want to use a sliding X since I am without a cordellet for right now. As there is no Top-Shelf for the redirect, whats the best method to set this up so I can belay off my harness? Also, I'm usuing a B-52. If I want a direct belay, can I just clip another locker in to the belay anchor? Thanks Oh yes, question refers to a two bolt achor system, not trad. Instead of messing with the anchor system for a redirect, can I just clip a quickdraw into either bolt and use that? This may not be the textbook answer, but if the bolts look bomber, I'll set up the sliding x off a locker to each bolt hanger, and clip myself to it with another sling girth hitched to the harness proper and a locker to the sliding x. I will then back myself up with the rope to one of the bolts, say the right one, and tie a clove hitch directly to the locker. I leave the rope a bit slack. Next I'll clip a draw to the left hand locker and redirect the belay through this. Ok. So, its not perfectly equalized. If the second falls, twice his or her weight is on that one bolt. This common misconception is false. A clean toprope fall will weight the anchor by at least 3 times the climber's body weight. That assumes there is absolutely no slack in the rope. With slack, the impact force can be much higher. Consider what might be the worst case scenario. Say the climber fell making the last move to the anchor, and impacted the rope before the belayer could take up any of the slack, producing, say, a 2-foot fall onto three feet of rope—a factor-0.67 fall. Then the impact force on the anchor would be on the order of 12 times the climber's body weight. With a 200-lb climber, the anchor would feel about 2600 lb of force (11.5 kN). The bolt you think is bomber better had be. Jay
I think what you are stating is more true if the climber is belayed in guide mode off an atc or grigri. Then I have no particular argument against the notion that the closer the seconding climber gets to the belay the higher the forces, especially with a slack belay and a static catch.
But...with a redirected belay, the falling second will typically lift up the belayer somewhat if the forces are substantial. Pulley effect will generally at least double the seconds weight as far as forces on the bolt, but I think your case is at least somewhat overstated. We're not tying the second off with a clove-hitch and having her take a plunker onto the bolt, which no doubt could generate the forces you describe.
As stated previously, I wouldn't use a guide mode type belay hanging from a single bolt.
What's your typical set-up with regards to the OPs query?
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jt512
Apr 22, 2010, 6:26 PM
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dugl33 wrote: jt512 wrote: dugl33 wrote: absinthe52 wrote: I want to use a sliding X since I am without a cordellet for right now. As there is no Top-Shelf for the redirect, whats the best method to set this up so I can belay off my harness? Also, I'm usuing a B-52. If I want a direct belay, can I just clip another locker in to the belay anchor? Thanks Oh yes, question refers to a two bolt achor system, not trad. Instead of messing with the anchor system for a redirect, can I just clip a quickdraw into either bolt and use that? This may not be the textbook answer, but if the bolts look bomber, I'll set up the sliding x off a locker to each bolt hanger, and clip myself to it with another sling girth hitched to the harness proper and a locker to the sliding x. I will then back myself up with the rope to one of the bolts, say the right one, and tie a clove hitch directly to the locker. I leave the rope a bit slack. Next I'll clip a draw to the left hand locker and redirect the belay through this. Ok. So, its not perfectly equalized. If the second falls, twice his or her weight is on that one bolt. This common misconception is false. A clean toprope fall will weight the anchor by at least 3 times the climber's body weight. That assumes there is absolutely no slack in the rope. With slack, the impact force can be much higher. Consider what might be the worst case scenario. Say the climber fell making the last move to the anchor, and impacted the rope before the belayer could take up any of the slack, producing, say, a 2-foot fall onto three feet of rope—a factor-0.67 fall. Then the impact force on the anchor would be on the order of 12 times the climber's body weight. With a 200-lb climber, the anchor would feel about 2600 lb of force (11.5 kN). The bolt you think is bomber better had be. Jay I think what you are stating is more true if the climber is belayed in guide mode off an atc or grigri.
No. For a factor-0 fall (toprope fall with no slack), the force on the anchor would still be three times the climber's weight, and for higher factor falls, the force on the anchor would be greater, but less than that caused by a static redirected belay.
In reply to: But...with a redirected belay, the falling second will typically lift up the belayer somewhat if the forces are substantial.
True, but the minimum force on the anchor will still be triple, not double, the belayer's weight.
In reply to: Pulley effect will generally at least double the seconds weight as far as forces on the bolt..
No. Friction reduces the pulley effect to around 5/3. With no pulley effect at all, a toprope fall with no slack in the system will weight the anchor two times the climber's body weight. With pulley effect, the anchor feels (5/3)*2 time the climber's weight. Slack in the rope increases the force.
In reply to: What's your typical set-up with regards to the OPs query?
I don't think I have such a standard setup. I have redirected the belay off of a single bolt, but I have also redirected through a dedicated sliding X not a part of the anchor.
Jay
(This post was edited by jt512 on Apr 22, 2010, 6:27 PM)
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william.alan.swanson
Apr 22, 2010, 6:39 PM
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dingus wrote: On two good bolts I wouldn't bother with a sliding X, a cordalette or any other gimmicky belay knotting arrangement. Two draws, knot knot, clip clip, DONE. Redirect with a biner added to one of the draws, if necessary. I rarely redirect. KISS. DMT
+1
On two bomber bolts, just clove hitch in line. Then belay off of your harness, through a redirect, or *gasp* with an autoblocking device on one of the bolts. They're bomber, remember?
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dugl33
Apr 22, 2010, 6:44 PM
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jt512 wrote: dugl33 wrote: jt512 wrote: dugl33 wrote: absinthe52 wrote: I want to use a sliding X since I am without a cordellet for right now. As there is no Top-Shelf for the redirect, whats the best method to set this up so I can belay off my harness? Also, I'm usuing a B-52. If I want a direct belay, can I just clip another locker in to the belay anchor? Thanks Oh yes, question refers to a two bolt achor system, not trad. Instead of messing with the anchor system for a redirect, can I just clip a quickdraw into either bolt and use that? This may not be the textbook answer, but if the bolts look bomber, I'll set up the sliding x off a locker to each bolt hanger, and clip myself to it with another sling girth hitched to the harness proper and a locker to the sliding x. I will then back myself up with the rope to one of the bolts, say the right one, and tie a clove hitch directly to the locker. I leave the rope a bit slack. Next I'll clip a draw to the left hand locker and redirect the belay through this. Ok. So, its not perfectly equalized. If the second falls, twice his or her weight is on that one bolt. This common misconception is false. A clean toprope fall will weight the anchor by at least 3 times the climber's body weight. That assumes there is absolutely no slack in the rope. With slack, the impact force can be much higher. Consider what might be the worst case scenario. Say the climber fell making the last move to the anchor, and impacted the rope before the belayer could take up any of the slack, producing, say, a 2-foot fall onto three feet of rope—a factor-0.67 fall. Then the impact force on the anchor would be on the order of 12 times the climber's body weight. With a 200-lb climber, the anchor would feel about 2600 lb of force (11.5 kN). The bolt you think is bomber better had be. Jay I think what you are stating is more true if the climber is belayed in guide mode off an atc or grigri. No. For a factor-0 fall (toprope fall with no slack), the force on the anchor would still be three times the climber's weight, and for higher factor falls, the force on the anchor would be greater, but less than that caused by a static redirected belay. In reply to: But...with a redirected belay, the falling second will typically lift up the belayer somewhat if the forces are substantial. True, but the minimum force on the anchor will still be triple, not double, the belayer's weight. In reply to: Pulley effect will generally at least double the seconds weight as far as forces on the bolt..No. Friction reduces the pulley effect to around 5/3. With no pulley effect at all, a toprope fall with no slack in the system will weight the anchor two times the climber's body weight. With pulley effect, the anchor feels (5/3)*2 time the climber's weight. Slack in the rope increases the force. In reply to: What's your typical set-up with regards to the OPs query? I don't think I have such a standard setup. I have redirected the belay off of a single bolt, but I have also redirected through a dedicated sliding X not a part of the anchor. Jay
1.) I agree that friction reduces pulley effect. No argument there.
2.) How does a reduction in pulley effect result in *67% more force?
*5/3 = 1.6666...
Are you sure you don't mean 3/5, i.e. reducing for friction, factor 0 hang, (weight)(3/5)(2)= 1.2 x weight?
If you put a weight on a string, run it through a pulley, tie off the other side, carefully hang the weight, the force on the pulleys connection will equal 2 x weight, not 3 x weight. Same experiment with friction, the force must be less than 2x weight.
Edit to add: my apologies here. What I really meant to say was the sum of modest dynamic forces and the pulley effect will generally at least double the climbers weight with regards to forces on the bolt.
(This post was edited by dugl33 on Apr 22, 2010, 7:06 PM)
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antiqued
Apr 22, 2010, 7:37 PM
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cfnubbler wrote: I see no reason to double the potential load on my anchors when I don't need to. Of course a modern bolted anchor is more than strong enough for such a load, but I still prefer to avoid it. YMMV.
Mileage does vary - for me, the situations I listed suggest a redirect. You obviously can cope. I just can't figure out how to supply "aggressive tension" with one hand (Prusik?).
And as far as doubling the potential load, if I was in any way uncomfortable with ~3kN on a bolt, I would be equalizing the two of them, if not backing them up or bailing. Your partner is leading through on this, isnt' he?
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ptlong
Apr 22, 2010, 7:57 PM
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dugl33 wrote: If you put a weight on a string, run it through a pulley, tie off the other side, carefully hang the weight, the force on the pulleys connection will equal 2 x weight, not 3 x weight. Same experiment with friction, the force must be less than 2x weight.
The key is that in a toprope fall the climber doesn't carefully hang his weight on the rope, he falls onto it. If the climber gently eased onto the rope the tension would equal his weight, and the force on the top piece would be about 5/3 his weight. But when the climber falls onto a rope with no slack and no initial tension, he first falls past the equilibrium point. At the low point of this fall the tension in the rope would theoretically be twice his weight, and the force on the top piece 5/3 of that, or 3.3 times his weight.
The only thing Jay left out is that the simple analysis assumes a belay tied off statically a foot below the redirect, and a dead weight on the other end. The dynamics of a real belayer and the give in a real climber in a fall of just two feet would significantly reduce the predicted force. Unfortunately there's no easy formula to calculate this.
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dugl33
Apr 22, 2010, 8:36 PM
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ptlong wrote: dugl33 wrote: If you put a weight on a string, run it through a pulley, tie off the other side, carefully hang the weight, the force on the pulleys connection will equal 2 x weight, not 3 x weight. Same experiment with friction, the force must be less than 2x weight. The key is that in a toprope fall the climber doesn't carefully hang his weight on the rope, he falls onto it. If the climber gently eased onto the rope the tension would equal his weight, and the force on the top piece would be about 5/3 his weight. But when the climber falls onto a rope with no slack and no initial tension, he first falls past the equilibrium point. At the low point of this fall the tension in the rope would theoretically be twice his weight, and the force on the top piece 5/3 of that, or 3.3 times his weight. The only thing Jay left out is that the simple analysis assumes a belay tied off statically a foot below the redirect, and a dead weight on the other end. The dynamics of a real belayer and the give in a real climber in a fall of just two feet would significantly reduce the predicted force. Unfortunately there's no easy formula to calculate this.
Oh man you guys are killing me. I started out merely trying to point out the downside of a redirect is the force multiplier of the pulley effect.
edit -- 5/3 does not equal 3.3 ok, on second glance you're not really saying this, but you are also not backing up your statement regarding tension theoretically being 2x weight. [Its as if you are calculating tension in a pendulum swing now (??)]
I imagine Jay meant to say 5/3 x weight, but he did not say this, he said 5/3 x 2 x weight.
When I say "carefully hang the weight" I'm just trying to isolate in simple terms static forces from dynamic forces, and point out that the force multiplier from just the pulley effect is 2.0 x or less. It will never be exactly 2.0 because even pulleys are not entirely without friction, much less biners.
(If you really wanted to figure out the force on the bolt the best way would be to empirically measure it with a strain gauge, otherwise you have to consider the seconds weight, fall distance, friction- slide or freefall properties of the second's fall, other friction of the rope running through gear and features below, how much rope is out, dynamic properties of the rope at that moment in time, knot style, air density, surface area of the second, pulley effect reduced by friction, the belayers weight and dynamic give when the belayer gets lifted up a bit... )
(This post was edited by dugl33 on Apr 22, 2010, 8:58 PM)
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ptlong
Apr 22, 2010, 8:55 PM
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dugl33 wrote: 5/3 does not equal 3.3
Yes, but 5/3 x 2 = 3.3.
In reply to: If the second falls, twice his or her weight is on that one bolt.
Maybe your intention was to only talk about the pulley effect but that's not what what you originally said. The load on the bolt will be at least three times the climber's weight, and possibly much more. Not twice the weight.
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ptlong
Apr 22, 2010, 9:11 PM
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dugl33 wrote: edit -- 5/3 does not equal 3.3 ok, on second glance you're not really saying this, but you are also not backing up your statement regarding tension theoretically being 2x weight. [Its as if you are calculating tension in a pendulum swing now (??)]
You want to see the math?
Richard Goldstone has already done this quite nicely for us:
http://www.rockclimbing.com/...ent;postatt_id=2957;
Here's a quote from page 3:
"There is a consequence of Equation (10) that seems little appreciated in the climbing
world. Simply weighting a rope, rather than having it catch a fall, corresponds to a fall
factor r = 0. For that fall factor, we find that T = 2w; the maximum tension in the
climbing rope is double the climber’s weight. What happens when a rope is weighted is that
it stretches until the maximum tension is twice the climber’s weight, and then recovers to
the point that the tension in the rope is just the climber’s weight. But the anchor will be
momentarily subjected to double the climber’s weight."
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dugl33
Apr 22, 2010, 9:25 PM
Post #24 of 30
(13283 views)
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Registered: Oct 6, 2009
Posts: 740
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see edit above. between you and me and Jay we're going in circles.
My original statement was merely a broad, general statement to point out the downside of a redirect is the pulley effect. From this, Jay took us into the realm of worst case thousands of pounds of load, simultaneously arguing friction reduces pulley effect yet mathematically magnifying this effect, i believe in error. If the max pulley is effect is 2 x, or lets call it 6/3, we could allow for friction and call it not 6/3 but rather 5/3. We can not however call it 5/3 times 2. Its 5/3 instead of 2.
Jay also was analyzing his worst case without allowing for the fact that a belayer would be lifted up in such a severe pull, which would reduce substantially max forces on the bolt. You can't have it both ways, acting as if there is no give with regards to the catch (as if its tied off at the bolt), and also magnify this scenario by pulley effect.
Now you are coming from an entirely different direction. I can't tell if now you are talking in generalities or specifics. You state a theoretical tension based on what exactly. (It seems like you are calculating multiples of G at the bottom of a swing or something)
Also, 3 times load on a big 200 pounder is only 600 lbs, not the massive 11kn worst case from Jay.
Also, I weigh about 150 lbs. Once the tension on my side of the biner exceeds this I'm travelling toward the draw, reducing peak loading on the bolt.
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dugl33
Apr 22, 2010, 9:31 PM
Post #25 of 30
(13281 views)
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Registered: Oct 6, 2009
Posts: 740
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I get a file warning clicking on that link....not sure I want to open that.
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