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Clevis fastener used for anchor...safe?
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Yyonnx


Apr 29, 2015, 6:37 PM
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Clevis fastener used for anchor...safe?
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Yesterday, at the top of a crack route, Blue Mountain, at Kofu Makuiwa, in central Japan, I found a newly installed anchor off the two existing bolts. Where there had been a heavy rope anchor which was in need of replacing there is now an anchor composed of a clevis fastener on each bolt with thin chains that have been brought together in a V with another clevis fastener. Two non-locking carabiners are then clipped thru the clevis fastener at the bottom of the V although unless they are perfectly aligned in the fastener, they lie askew.

The remains of the old, rope anchor tat was left where it fell at the base of the climb.

I am familiar with clevis fasteners use in the sailing world but running across them in this capacity I was surprised and concerned.

Feedback on the safety of the fasteners would be appreciated.

Thank you!


sbaclimber


Apr 30, 2015, 1:30 AM
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Re: [Yyonnx] Clevis fastener used for anchor...safe? [In reply to]
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You mean a DYI version of this?

Depending on the quality and size of the shackles and chains, the anchor could be just fine.
I have seen and used many anchors set up in a similar manner.


Yyonnx


Apr 30, 2015, 1:46 AM
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Re: [sbaclimber] Clevis fastener used for anchor...safe? [In reply to]
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Yes, in general shape. Both the chain and shackle are small...I've tried twice to upload a picture I took yesterday of the actual shackle and chain set up but I am unable to upload the jpg file.

Thank you for your response.


dagibbs


Apr 30, 2015, 6:50 AM
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Re: [Yyonnx] Clevis fastener used for anchor...safe? [In reply to]
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Probably more than safe enough for a rappel/lower off. I wouldn't top-rope through the gear, but I prefer to not top-rope through in-place gear, anyway.

I would hope that they picked compatible metal to the bolts and hangers. (All stainless.)


kennoyce


Apr 30, 2015, 12:12 PM
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Re: [Yyonnx] Clevis fastener used for anchor...safe? [In reply to]
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Yyonnx wrote:
Yesterday, at the top of a crack route, Blue Mountain, at Kofu Makuiwa, in central Japan, I found a newly installed anchor off the two existing bolts. Where there had been a heavy rope anchor which was in need of replacing there is now an anchor composed of a clevis fastener on each bolt with thin chains that have been brought together in a V with another clevis fastener. Two non-locking carabiners are then clipped thru the clevis fastener at the bottom of the V although unless they are perfectly aligned in the fastener, they lie askew.

The remains of the old, rope anchor tat was left where it fell at the base of the climb.

I am familiar with clevis fasteners use in the sailing world but running across them in this capacity I was surprised and concerned.

Feedback on the safety of the fasteners would be appreciated.

Thank you!

As long as the shackles and chains are sufficiently strong then there is no problem. check the size of each, and I'm sure you could find the approximate strength ratings for each on the google. Keep in mind that the strength ratings are generally a safe working load which is usually about 1/4 or 1/5 of the average breaking strength.


Yyonnx


Apr 30, 2015, 6:44 PM
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Re: [kennoyce] Clevis fastener used for anchor...safe? [In reply to]
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Appreciate the comments, feeling better about the set up.

Thanks!


JimTitt


May 1, 2015, 12:15 AM
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Re: [Yyonnx] Clevis fastener used for anchor...safe? [In reply to]
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Depends on the quality of the components obviously but mostly the chains and connectors used on top-anchors are total overkill. The standard chains in Euro chainsets are usually 8mm long link because that is the size needed to install the other components and have links big enough to clip karabiners into, I sometimes use 6mm chain for linking bolts where you wonīt need to clip in which is also overkill really when it comes to strength, in fact one manufacturer uses their own welded links from 6mm as standard. The typical monster chain used in american chain-sets is more to do with needing to be able to thread the rope through than anything to do with strength, especially considering some of the bolts itīs usually attatched to.
That they managed to install two karabiners into the clevis connection indicates its probably gigantic!

If you do research chain strength youīll find all sorts of wierd things like an identical chain will get different ratings under ANSI (American) and DIN/EN (Euro) because the breaking strength is a nominal number obtained using a weld strength factor which varies from country to country and the working load is basically where the links donīt distort. So you can buy 8mm stainless chain with a max working load of 460kg, a breaking strength of 2500kg and test it and it actually fails at 5800kg.


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