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PostPosted: Thu Feb 18, 2010 8:53 pm 
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The Pub Czar
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David Goulet wrote:
..... that really clears things up :? ....


the executive summary is:
"i am not going on a date this weekend"

err, i mean:
"the butterfly + carabiner has two things that can break. either one breaking means you die.
the bowline + carabiner also has two things that can break, but you need both to break in order to die, thus it is theoretically safer."

obadiah and i were talking about how much safer the bowline method is in theory.

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PostPosted: Thu Feb 18, 2010 9:20 pm 
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A different option - figure of eight tied on a bight with locking carabiner? I've seen this done pretty often as well, how does it compare to bowline/biner?


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PostPosted: Thu Feb 18, 2010 9:41 pm 
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Carolina wrote:
A different option - figure of eight tied on a bight with locking carabiner? I've seen this done pretty often as well, how does it compare to bowline/biner?


According to the very limited "theory" Amittai and I were discussing, the figure eight and the bowline w/ caribiner backups would be identical. However if the f-8 is less likely to untie, then it would still come out as the winner.


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PostPosted: Thu Feb 18, 2010 9:48 pm 
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I think the advantage of the bowline on a bite with a biner is that you are actually tied into the rope with the biner ensuring the knot can't come untied, while the figure eight on a bite is clipped to a biner which is then clipped to your harness, adding one more point of failure to the system.

I asked this question because my parents bought me a copy of the Mountaineering Handbook, in which the author strongly advocates tying in with the Yosemite bowline (check out pages 137-139 on the Google Book link), but he does seem to be a lone voice in the wilderness on this point. I think a key point is that he recommends the bowline with a Yosemite finish, which I think is critical. If it really is a superior knot (which I'm not convinced of) the argument that it shouldn't be used because people aren't familiar with it seems a weak one; after all, there was a time when none of us knew what a figure eight was.

All that being said, for now I think I'll stick with my trusty figure eight in critical situations and play with the Yosemite bowline on a sailboat.


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PostPosted: Thu Feb 18, 2010 11:16 pm 
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The Pub Czar
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Lee Willcockson wrote:
If it really is a superior knot (which I'm not convinced of) the argument that it shouldn't be used because people aren't familiar with it seems a weak one; after all, there was a time when none of us knew what a figure eight was.


what they mean by "familiar" is "experienced".
the drawback to the yosemite bowline is not that it's novel, it's that in practice it requires more experience (or focus, or time) to visually verify if it has been tied correctly.
from the accident reports, it seems like people using the knot sometimes don't spot when they've mis-tied it.

the figure-8 is a safe enough knot, but its major advantage over the yosemite knot in this case is that it's really easy to visually verify that it has been tied correctly. if you've seen the knot tied correctly once, you can check it. "keep it simple".

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PostPosted: Sun Feb 21, 2010 8:04 pm 
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veronika glukhova wrote:
i tie into a fig 8 when i'm likely to be caught by a climbing gym employee.


I was happily using your retraced bowline, but just got caught and now have to use the 8.


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PostPosted: Sun Feb 21, 2010 10:58 pm 
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Tenacious Lee
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So for this retraced bowline you tie a regular bowline and use the tail to retrace the knot starting at the original bight? Do you retrace the entire knot, or just the bight? I couldn't seem to find a comprehensive description online.


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PostPosted: Mon Feb 22, 2010 10:04 pm 
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Awesome, thanks Veronika.


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PostPosted: Tue May 11, 2010 5:26 pm 
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Jim Prager wrote:
As far as glacier travel goes, I would say that a bowline on a bight backed up with a locking 'biner has to be more reliable than just the alpine butterfly + 'biner. I use this system (bowline + biner backup) when I tie in at the middle of a half rope for simul-climbing or short pitches. Perhaps I should be doing a rewoven 8 on a bight (?).


Personally, I use a rewoven overhand knot on a bight. Take a bight of rope, tie an overhand knot. Then pass the bight of rope through the loops in your harness and reweave the overhand knot. You should then clip a locking biner into the free bight of rope and attach it to your belay loop or a gear loop. It is generally safer to tie directly into the harness without using a biner because the biner could fail, e.g., the rope rubbing on the gate could accidentally open it. In my case, the biner is just a backup.

Theoretically, you could use a rewoven 8 on a bight but you will end up with a huge knot to carry around.


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PostPosted: Thu May 13, 2010 7:27 am 
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One Armed Wonder
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Obadiah Reid wrote:
David Goulet wrote:

Entropy: out of all possible arrangements of the system, there are fractionally more ways to die with the butterfly+biner system.

Its early in the morning,and my coffee perhaps is not settled in, but where is the 'biner backup' of a bowline? Using load->biner->knot configuration, It looks like there are just as many configurations to fail. If somehow it is load->knot->backup, then there is only one option of failure. However, if the knots in these two different configurations have a different overall probability of failure, then the exp(entropy) aka, number of possible failure mechanisms argument doesn't work. Namely, what I am saying is that it is not the total # of of possible failures within a system, but the product of the potential failure rates of which determines the likelihood of failure.

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PostPosted: Fri May 14, 2010 6:10 pm 
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I do use the Double Bowline to tie the climbing rope to my harness. A Double Bowline is only slightly different than the standard Bowline. The difference being that while you're giving the story which guides you how to form and tie the knot, you place two coils of rope. The "rabbit" comes up from the ground through two coils of rope, or the "stage hand" comes out of the bar through two coils of rope, etc.

I then form a double overhand with the tail. This double overhand knot is tied around the bowline's primary load loop strand.

The tail from the double overhand is appropriately long. For round textiles the recommended tail length is 10 times the diameter of the textile. For flat textiles the recommended tail length is 6 times he width of the textile.

10mm ropes need 100mm tails, about 4 inches.
1-inch webbing needs 6-inch tails.

These recommendations are from the bible on all things rope, "On Rope" by Pagett.

Most of my partners also use the Double Bowline. Most use the Yosemite Finish rather than the Double Overhand. The Yos finish is where you take the tail and feed it back through the acute bight in the Bowline. Lee's original post had excellent pictures showing the Yosemite Finish to the Bowline.


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PostPosted: Wed Jun 23, 2010 4:35 pm 
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When I can get away with it, I like to tie in as shown in Lee's original post (single bowline with a Yosemite finish), but I additionally tie the tail to the standing part with a double overhand (like most people finish their retraced figure eights).

My favorite method for tying a single bowline starts with a simple flip of the bitter end around the standing part. In this case, a video is worth a thousand words.
http://www.youtube.com/watch?v=57CTfXEk7qk
Starting in this way avoids the need to futz around with properly orienting the "rabbit hole" and comes almost mindlessly to the hands -- poetry in motion.


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