Hauling off One Bolt or Two?
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Hudon recommends (and it is what I've always done) hauling off only one bolt, with a second bolt as backup. What is the best way to backup the haul if hauling only off one bolt? Using his anchor system, the big locker would be clipped to the lead line which would be clipped to two other bolts? Is this sufficient? I've always run another sling from my haul biner to the far outside bolt as well. |
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Jace Mullen wrote:Hudon recommends (and it is what I've always done) hauling off only one bolt, with a second bolt as backup. What is the best way to backup the haul if hauling only off one bolt? Using his anchor system, the big locker would be clipped to the lead line which would be clipped to two other bolts? Is this sufficient? I've always run another sling from my haul biner to the far outside bolt as well. Benefits include using less gear, and having the haul up higher, increasing efficiency. Assuming a bomber 3/8" bolt, this should be safe, yeah? How do you set up your haul vis-a-vis the anchor?I just haul off a 3' sliding x on two bolts. I am not sure what the advantage of just using one bolt would be. In any case, the haul bag should be treated as a live person. If you mess something up and the haul bag goes for a whip, it will likely kill you and/ or your partner. Think about where you anchored the end of the haul line. You just finished leading a pitch, you unclip the haul line from your haul loop, and then what? Most people clip it to the anchor. So if the bag goes flying, that 150 lbs of crap taking a 100 - 200 foot whipper on a static line which will end at your belay station. Something to think about. |
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I know that most of the baddasses of bigwall climbing only use static haul lines but I have a huge hang-up with this. The possibility of anything in my system possessing the power to strip a whole team team off of a wall is unacceptable to me. |
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Bob Dobalina wrote: The worst part would be those terrifying moments between realizing that the bag became unclipped from the anchor, and the moment that it hits the anchor again at the end of the rope.Actually I think the worst part would be after the bag hits the anchor and you go into a freefall toward the ground. |
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Bob Dobalina wrote:I know that most of the baddasses of bigwall climbing only use static haul lines but I have a huge hang-up with this. The possibility of anything in my system possessing the power to strip a whole team team off of a wall is unacceptable to me. Any math geeks care to quantify the force generated when a 150lb weight falls 200 ft and static shock-loads an anchor? The worst part would be those terrifying moments between realizing that the bag became unclipped from the anchor, and the moment that it hits the anchor again at the end of the rope.Agreed. Though the impact for is unlikely to break good bolts in good rock. Despite the big numbers of 200ft is simply a maximum factor 1 fall on a static rope. I think we'd be talking around 10kN. This article shows figures up to 15kN but it uses ultra fat statics. web.mit.edu/sp255/www/refer… Belaying off a single bolt with a second as backup is common in Europe. Good bolts in good rock etc, this system is fine. But it isn't something I would do. I statically equalise. |
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personally I always haul on 2 bolts although 1 good bolt should be enough. I also back up my hauling device with a draw unles I'm using a 2:1 which also counts as a back up |
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I think that hauling off of two (equalized) bolts is crucial from a safety standpoint. Especially in sandstone. A heavy haulbag taking a full rope plunge onto a static line is similar to having a giant "funkness device" attached to your anchor. |
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The only reason you would want to haul off a single bolt, rather than two or more equalized, is when your haul anchors are above a ledge. Hauling off a single bolt keeps the haul device higher above the ledge than if you equalize two bolts, meaning that the haul line bends less across the front of the ledge, and hence you lose less of your effort to friction of the haul line passing across the ledge. |
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ah, my opinion? Why not haul off two bolts? Clove hitch to keep the haul point as high as possible, but you certainly have enough anchor strength. |
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caribouman1052 wrote: A Yates Zipper will handle 9kN, which would take out more than half of the proposed max load of 15kN.The values on Yates' website are total BS. A screamer wont do jack in a scenario where a haul bag falls the length of a rope onto the anchor. Screamers are only effective in very short falls involving low amounts of energy (e.g. you fall on a RURP with the piece at your foot). You are correct that you remove the extra slack from the system before hauling, but that does not happen instantly, it takes time, and something could go wrong before you're done managing the rope. I am simply illustrating that a mess up with the haul bag could be lethal--there are a number of examples and scenarios where that could happen. caribouman1052 wrote: Also, is it possible that the material in the haul bag would blow out the bottom, relieving the load on the anchor?Possible but not likely. Most haul bags have full strength 1" webbing that crosses at the bottom of the bag to allow you to connect a second bag. That webbing runs the length of the haul bag and forms the connection points at the top of the bag. It's more likely the contents would rip out of the side of the bag at the end of the fall since the side of the bag is not reinforced; however, who knows what would happen. I think the bag would remain mostly in tact, and if it did explode it wouldn't do it without first generating massive forces. |
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99% of the anchors on El Cap or Half Dome for 99% of the people posting on this site will be three modern 3/8" bolts. |
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Whatever you do make sure you dont step on a bolt. heehee |
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I'm confused as to how a bolt failure will result in a haul bag falling the entire length of the rope? If you have an anchor made of the available bolts at an anchor, the failure of one bolt will result in a few feet drop maximum before the rest of the anchor catches the hauling device which holds the bag wherever it was in the hauling process? Are we assuming that the hauling device will deform and fail as well from the momentary drop? If we are, no one seemed to mention it that I noticed as I glossed over the thread. |