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9-Mar-2014 10:47:37 AM
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Correct photo is with the gate facing down. My phone shows original photo as correct. When I checked on my computer, original photo was incorrect. Weird. Correct photo is the one with the gate on the bottom of the photo, which ever one that is. Biner has spun 90 degrees anticlockwise. Wall is just over vertical. Sorry about the confusion....
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9-Mar-2014 10:55:27 AM
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On 9/03/2014 tristosterone wrote:
>Correct photo is with the gate facing down. My phone shows original photo
>as correct. When I checked on my computer, original photo was incorrect.
>Weird. Correct photo is the one with the gate on the bottom of the photo,
>which ever one that is. Biner has spun 90 degrees anticlockwise. Wall is
>just over vertical. Sorry about the confusion....
This way is correct then?
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9-Mar-2014 11:17:39 AM
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Now I am getting pretty confused, as the photo is still different between my computer and my iPhone. It should be in the direction of my drawing below.
If what you see is in that direction, it is correct.
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9-Mar-2014 2:00:40 PM
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Has the biner itself been deformed compared to similar biners? I don't have similar quickdraws, but the biners on my quickdraws all seem to curve more and not have a flat bit like the one that's snagged in between the bolt and the plate on yours... I wouldn't be surprised if rope-drag and traversing a bit above the bolt can somehow make the biner cam in like that if the dogbone isn't sitting on the flat bit of your biner (especially, as Neil suggested, if the bolt is sitting on a very overhanging part of the wall where the quickdraw will start following the wall in the wrong direction); but that's all just a guess. Probably best to send the image to the manufacturer so that their engineers can have a proper think about it?
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9-Mar-2014 4:56:28 PM
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One of the reasons this has occurred is that the biner has got jammed between the extruded bolt head (nut+thread) and the hanger eye. As Kent mentioned previously, the more the bolt sticks out of the rock the more chance this will happen. This bolt isn't extruded any more than usual - but it can still cause a problem. This can't really happen with ringbolts or ubolts - and with flushhead expansion bolts it will have less chance of happening.
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9-Mar-2014 5:02:12 PM
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I've seen my quickdraws slip into that position on several occasions - I realized it was dangerous but I could do nothing about them when it happens a few bolts below. Lucky I have never fallen off on one of them directly. If at any time a quickdraw sits at a position not naturally hung by gravity you should be concerned, as it is wedged/stuck in a dangerous position. Biners are only strong when the weight is on the top and bottom - cross loading, or even worse - loading the gate is very dangerous. The other danger to look out for is when a biner is bent over an edge. They will happily bend and break in this situation.
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9-Mar-2014 7:04:11 PM
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While we're on the topic there's these two ways to accidentally get a draw off a bolt:
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10-Mar-2014 1:39:25 AM
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Now I have worked out what has happened I have come to a few conclusions. This actually was a pretty freaky accident. I recon it's pretty rare for a rope to pull the draw directly below you into a configuration we saw between the biner and hanger. Then (correct me if I am wrong), if this does happen, the majority if falls are simply going to cross load the biner. Such cross loading is an issue, but you still have 8kn or so to play with. The issue with my fall is I was pulling outwards on a tufa that broke, causing my fall to not be just down but also a fair way out from the cliff. This outwards fall and hence outwards force on the gate is what disengaged the gate. A similar issue could occur on steep ground. So it was freaky. But it can happen. And maybe being more conscious of how the draw below you is sitting (especially for the first 3 or so) is a really good idea. And if I was designing hangers, maybe I would put the hole of the hanger and the nut/bolt a bit more of a distance from each other so the draw and the nut/bolt can't interact. But I am not a design engineer...
Thanks for helping me work through this guys!!
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