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#65904 - 07/16/12 08:54 AM Yosemite bowline is not safe for climbing
stefanfischer Offline
stranger

Registered: 07/16/12
Posts: 1
Hi,
just wanted to draw your attention to this new video, in case anyone here uses the bowline with the Yosemite finish when climbing. The video shows that finishing the bowline like that actually unties the knot!

http://www.youtube.com/watch?v=1dj5Y3h1AEI

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#65907 - 07/16/12 03:24 PM Re: Yosemite bowline is not safe for climbing [Re: stefanfischer]
chip Offline
Carpal Tunnel

Registered: 10/06/01
Posts: 2677
Loc: Sittin' Pretty in Fat City
That was excellent. Thanks.

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#65911 - 07/16/12 08:52 PM Re: Yosemite bowline is not safe for climbing [Re: chip]
rg@ofmc Offline
Pooh-Bah

Registered: 12/25/99
Posts: 2472
Loc: Poughkeepsie, NY
I'm not at the moment advocating one way or the other, and I think we have to thank Stefan for his work in any case, but I think it premature to say that the Yosemite finish "unties the knot." (And we have some evidence from a test just done by Jim Titt that this is not the case.)

For more on this, see the thread at UKC climbing,

http://www.ukclimbing.com/forums/t.php?n=513200.

My post discussing the issues is at

http://www.ukclimbing.com/forums/t.php?t=513200&v=1#x6950860

and Jim Titt's response with his test is at

http://www.ukclimbing.com/forums/t.php?t=513200&v=1#x6950948.

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#65912 - 07/16/12 09:19 PM Re: Yosemite bowline is not safe for climbing [Re: rg@ofmc]
NYZoo Offline
journeyman

Registered: 07/06/08
Posts: 59
Loc: Gunks
Here's a link to the same thread on the taco.

http://www.supertopo.com/climbers-forum/...mbing-after-all

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#65924 - 07/17/12 04:37 PM Re: Yosemite bowline is not safe for climbing [Re: NYZoo]
rg@ofmc Offline
Pooh-Bah

Registered: 12/25/99
Posts: 2472
Loc: Poughkeepsie, NY
Ok, I think this is officially a false alarm, based on more testing by Jim Titt. See the threads linked above.

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#65926 - 07/17/12 07:53 PM Re: Yosemite bowline is not safe for climbing [Re: rg@ofmc]
GOclimb Offline
Pooh-Bah

Registered: 03/26/01
Posts: 2361
Loc: Boston
Originally Posted By: rg@ofmc
Ok, I think this is officially a false alarm, based on more testing by Jim Titt. See the threads linked above.


Yes and no.

It is a false alarm in one sense: it has been clearly shown that with the Yosemite finish in it, the bowline is quite safe even if it has been subjected to this pulling on the "wrong" strand.

But it is not a false alarm in the sense that we have learned that there is a method, now documented, by which the Yosemite finish, when tied just so, and when the wrong strand is pulled, will modify the bowline, such that if the Yosemite finish is removed, the bowline no longer remains.

I do think the latter is worth noting, even if it's somewhat academic. Hard to know when it might come into play, but still well worth adding to the knowledge-base for future reference.

GO

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#65928 - 07/17/12 09:29 PM Re: Yosemite bowline is not safe for climbing [Re: GOclimb]
rg@ofmc Offline
Pooh-Bah

Registered: 12/25/99
Posts: 2472
Loc: Poughkeepsie, NY
Originally Posted By: GOclimb
Yes and no...


My comment about the false alarm is directed, naturally, at the title of the thread, and as far as the title is concerned, I don't think there is any need to equivocate.

But you have a point anyway, because it is possible that Jim's tests might have come out differently, in which case the fact that a relatively simple variation of the correct knot would have been catastrophic.

Hence, the video highlights the fact that it could be very dangerous to modify a known knot in a way that might seem intuitively advantageous. We have already seen this play out, tragically, with the substitution of a figure-8 knot for an overhand knot in the EDK. A second example is that at least some so-called Yosemite finishes, when added to a figure-8 loop, make it more prone to rolling.

The fact that a bowline does not remain after the transformed version is partially untied seems to me to be an artifact of terminology more than anything else. The bowline with Yosemite finish is a singe entity, regardless of its compound description. If you rearrange it and then undo part of the rearranged version, it shouldn't be much of a surprise if the starting configuration is no longer present.

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#65950 - 07/20/12 08:24 PM Re: Yosemite bowline is not safe for climbing [Re: rg@ofmc]
donald perry Offline
veteran

Registered: 06/27/11
Posts: 1530
Loc: New Jersey
I suppose you need to tie some half hitches, one girl died in Colorado from not having half-hitches for some reason.


Another problem with the boline is that if you load it on the loop [such as when you tie it directly *around* a tree, and then load it off *that loop*.] only it can come untied. I saw this happen once 30 years ago.
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