/ Yosemite bowline not safe for climbing

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stefanfischer on 16 Jul 2012 - host-62-245-219-245.customer.m-online.net
Here's a video that shows that when you finish up the bowline with the Yosemite finish, you are actually just untying the bowline:

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

Seems like the double-bowline (or rethreaded, or whatever it's called when the bowline goes twice through the harness) is safer after all?
Hephaestus - on 16 Jul 2012
In reply to stefanfischer: I don't have sound on my 'puter, but I think it's showing that you can mis-tie the yosemite bowline and that the result of that is not a knot. The relevant section - the mistake - is illustrated when they slip the top loop over the bottom loop. The same would go for pretty much any knot.
Justin T - on 16 Jul 2012
In reply to Hephaestus:

Actually it appears to show that if you mis-tie the knot in a fairly convoluted manner then jiggle it about in a totally unloaded, loose state you can end up with a slip-knot fig-8. I'm pretty sure that translates to "not safe for climbing" in much the same way as showing how a harness can come undone if not doubled-back shows a harness is "not safe for climbing".
sarahlizzy - on 16 Jul 2012
In reply to stefanfischer:

It's notable that he didn't set the knot before threading the Yosemite finish, which allowed the two loops to change places. If the knot is set first, this won't happen when climbing because it requires an upward pull on the Yosemite finish to slip it under the other loop; that won't happen because the Yosemite finish is just a tuck and not load bearing whereas the other loop is.

However, as a user of the Yosemite, it is disturbing that this can happen, even if it requires a sloppy tying of the knot. I always add a standard grapevine stopper after tying the Yosemite finish, but perhaps I will investigate using the rethreaded bowline on a bight in future.
highclimber - on 16 Jul 2012
In reply to sarahlizzy:
> (In reply to stefanfischer)
>
>
> I always add a standard grapevine stopper after tying the Yosemite finish, but perhaps I will investigate using the rethreaded bowline on a bight in future.


I do exactly this too and I make sure the bowline is tight before doing the yosemite finish.

Without one example of this knot having ever failed I suspect this 'problem' is nothing to worry about so long as you're aware that it can happen. there are bigger worries like not tying in properply (or at all) and that has happened, with fatal consequences
PeteH - on 16 Jul 2012
This is stupid. The only learning point from the video is "Don't half-tie your knot, then fiddle around with it loads, then completely fail to set it before starting to climb." The function of most knots depends on their being properly set, and the behaviour of a loose knot which has not been set bears little relation to the finished form of a knot.

Bottom line? Whatever knot you use, tie it properly and double-check it with your partner.
sarahlizzy - on 16 Jul 2012
In reply to PeteH:
> This is stupid. The only learning point from the video is "Don't half-tie your knot, then fiddle around with it loads, then completely fail to set it before starting to climb." The function of most knots depends on their being properly set, and the behaviour of a loose knot which has not been set bears little relation to the finished form of a knot.

This is true, but the number of times I've seen people using knots that are not set or dressed is very high. I'd even go so far to say that it's rare to see someone using a dressed figure 8 (unset ones are still common, but less so IME).

As a Yosemite bowline user myself, I have to say that the figure eight seems to lack such a catastrophic failure mode when not properly set and dressed.
highclimber - on 16 Jul 2012
In reply to PeteH: I suppose a good analogy is changing the wheel of your car - if you put the wheel on and don't forget to torque the nuts up properly, your wheel might fall off and you'll die!
stefanfischer on 16 Jul 2012 - host-62-245-219-245.customer.m-online.net
In reply to PeteH:

I don't think the knot is not set - at the beginning of the video he makes the knot twice, and sets it too. He doesn't set the knot after the bowline, otherwise he won't get the yosemite finish in there.
But he makes the whole thing, and pulls it real tight.

On the first go, it seems to work, on the second it fails completely, but it still looks like a tight little yosemite bowline.

You can tie the knot as strong as you wish, but:
- If you pulled in the wrong order or to the wrong side or something, you don't have a bowline anymore.
- If you end the knot with a stopper, it won't help you either.
- Even if you tucked it in "correctly", and it looks like the knot in wikipedia, it still is equivalent to the simple figure 8 he shows there at the end. A strong fall might just flip the knot or something, because it is the figure 8 - no need to rethread anything for it to happen.
highclimber - on 16 Jul 2012
In reply to stefanfischer: No, he ties the Bowline initially and pulls it tight, then does the finish. in the second instance he pulls the yosemite first before tightening the bowline. I disagree with your belief that a stopper wouldnt help you. of course it would as with the yosemity finish in place, you still have an effective bowline, its only when you pull the finish out do you have what looks like a dangerous knot.
In reply to stefanfischer:

Why people don't just use a simple bowline, which has been used by generations of climbers (and many more generations of sailors) escape me.

http://www.youtube.com/watch?v=sP-jB5Vsv0s


Chris
stefanfischer on 16 Jul 2012 - host-62-245-219-245.customer.m-online.net
In reply to highclimber: Well, you're right about the difference between the first and second time - one time he pulls on the main rope first, the other time on the loose end first.
As a result - on the first time you have the bowline still there, on the second time there's no bowline anymore.
This alone is not something I'd bet my life on - on my getting the correct order of pulling each time.
If I pulled on the loose end a bit more, and the bottom loop slid up and opened my bowline, then a stopper won't help me either. When I fall I'm only being held by my stopper...
highclimber - on 16 Jul 2012
In reply to stefanfischer: The tail of the finish on the first is on the left. the tail of the second is on the right, which would indicate to me i'd tied it wrong.
stefanfischer on 16 Jul 2012 - host-62-245-219-245.customer.m-online.net
In reply to Chris Craggs: The bowline with a stopper is great.
I guess some people used to do that without a stopper - it then becomes undone when you continuously load and unload it.

Anyway, it sure doesn't depend on the order in which you tighten the knot! If you thread correctly and tighten it any way you like, you end up with a safe knot.
stefanfischer on 16 Jul 2012 - host-62-245-219-245.customer.m-online.net
In reply to highclimber: This has little significance - i managed to destroy the bowline with both the loose end on the left and on the right when I gave it a go.
And you can always just make a mistake on the sides there - it is still threaded correctly! That's the thing about this knot - you thread correctly, yet sometimes it's broken and sometimes not.
And since it's always threaded the same, who knows what a huge sudden load can do to this knot? When you fall, nothing gets unthreaded, but things could still open up there.
highclimber - on 16 Jul 2012
In reply to stefanfischer: I've just had a play with making the knot using one of my 7.8 twins and each time I tied the yosemite, the knot looked neat and like it should. only when I played with the way the tail went, when I physically place the loop through the bowline hitch, a la the video at 0:35s, did it create a slip knot on a bight when I pulled on the loop. this could be dangerous but highly unlikey to occur and given I always tie a stopper knot as well, this would mean it would be highly inconvenient though not dangerous per se.
Hephaestus - on 16 Jul 2012
In reply to stefanfischer:
> > And since it's always threaded the same,

That is not correct - in the second instance the knot is not tied properly. I could illustrate how any knot you care to mention is unsafe if instead of tying the knot, I am really just tangling up the ropes!

To note: it's easy to check whether you have correctly tied the yosemite or edwards variants of the bowline by turning the knot over after tying it. It's obvious if you've messed up.
Al Randall on 16 Jul 2012
In reply to Chris Craggs:
> (In reply to stefanfischer)
>
> Why people don't just use a simple bowline, which has been used by generations of climbers (and many more generations of sailors) escape me.
>
Totally agree. If it ain't broke why fix it. If everyone had stuck to the original perhaps we would not now be in the position of some walls banning the bowline.

Al
a lakeland climber on 16 Jul 2012
In reply to stefanfischer:
> That's the thing about this knot - you thread correctly, yet sometimes it's broken and sometimes not.

If you thread the Bowline correctly then it's a good knot. If the knot is "broken" (or comes apart when tugged) then you haven't threaded it correctly! There's no half measures.

ALC
PeteH - on 16 Jul 2012
In reply to stefanfischer:
> (In reply to PeteH)
>
> I don't think the knot is not set - at the beginning of the video he makes the knot twice, and sets it too. He doesn't set the knot after the bowline, otherwise he won't get the yosemite finish in there.
> But he makes the whole thing, and pulls it real tight.

At no point in this video does he set the knot in what I would consider to be an acceptable manner. Even the first time we see the "completed" knot (00:20) he hasn't tightened all the strands, there is still oodles of slack there.


> On the first go, it seems to work, on the second it fails completely, but it still looks like a tight little yosemite bowline.

Sorry, but I would certainly not consider his knot at 00:38 to be a "tight little Yosemite bowline". The way he is holding it in the video may make it resemble a Yosemite bowline, but if you tighten it up properly it looks like a completely different knot. I've just been playing around with this and it took me a while to figure out what he'd actually done at 00:36 in order to produce this knot (even though he explains it later!), but when you do produce that knot it's a totally different shape to the Yosemite bowline.

> You can tie the knot as strong as you wish, but:
> - If you pulled in the wrong order or to the wrong side or something, you don't have a bowline anymore.
> - If you end the knot with a stopper, it won't help you either.
> - Even if you tucked it in "correctly", and it looks like the knot in wikipedia, it still is equivalent to the simple figure 8 he shows there at the end. A strong fall might just flip the knot or something, because it is the figure 8 - no need to rethread anything for it to happen.

What he does towards the end (1:38-2:00) just demonstrates how important it is to correctly set and dress the knot - even if he had tightened it up after having tied it wrongly, there's no way the main load-bearing line could "straighten out" in the way he shows.

What I will certainly admit is that this video does demonstrate that it's easy to tie the Yosemite bowline incorrectly, which we knew anyway, and it's still for this reason, I think, that most outdoor centres and walls instruct people on the rethreaded figure-of-eight. I probably wouldn't teach the Yosemite bowline to someone new to the sport, because a figure-of-eight is easier to get right first time and harder to get wrong. But it doesn't do anything to discredit the reliability of a properly tied Yosemite bowline. If you're relying on a knot for your life then I'd strongly advise knowing it inside-out, and being able to recognise when it's not tied correctly...

jon on 16 Jul 2012
In reply to a lakeland climber:
> (In reply to stefanfischer)
> [...]
>
> If you thread the Bowline correctly (...)

Yes. If you thread it incorrectly, it isn't a bowline.
stefanfischer on 16 Jul 2012 - host-62-245-219-245.customer.m-online.net
In reply to a lakeland climber:

> If the knot is "broken" (or comes apart when tugged) then you haven't threaded it correctly! There's no half measures.

My point exactly. With the yosemite finish, you thread everything correctly, yet it comes apart when you tug on it in one specific order (loose end first).
This means the Yosemite finish breaks the bowline underneath - even if you tug the other way around. It's the same threading. And it doesn't matter if the loose end is on the right or on the left of the main rope - they both come through the loop at the top - it's exactly the same threading.
sarahlizzy - on 16 Jul 2012
In reply to highclimber:
> (In reply to stefanfischer) No, he ties the Bowline initially and pulls it tight, then does the finish. in the second instance he pulls the yosemite first before tightening the bowline.

In fact, watching carefully, he DOESN'T tighten the bowline on the second attempt. He pulls on the tailing end to tighten the whole assembly. This is what pulls the Yosemite "loop" through the other one.

It's a mistake I could see people doing when tying a Yosemite finish,but his assertion that "you don't have to do anything wrong for this to happen" is clearly not true. He didn't tie the knot properly.

highclimber - on 16 Jul 2012
In reply to stefanfischer:
> (In reply to a lakeland climber)
>
> [...]
>
> My point exactly. With the yosemite finish, you thread everything correctly, yet it comes apart when you tug on it in one specific order (loose end first).
> This means the Yosemite finish breaks the bowline underneath - even if you tug the other way around. It's the same threading. And it doesn't matter if the loose end is on the right or on the left of the main rope - they both come through the loop at the top - it's exactly the same threading.

My contention about the position of the tail after the finish was incorrect. I realised that after playing with it just then. Apologies.
sarahlizzy - on 16 Jul 2012
In reply to PeteH:

> What he does towards the end (1:38-2:00) just demonstrates how important it is to correctly set and dress the knot - even if he had tightened it up after having tied it wrongly, there's no way the main load-bearing line could "straighten out" in the way he shows.

I agree. In order to achieve the catastrophic failure he loads the knot in a way that simply wouldn't happen during a fall. Indeed, the pull on the standing part of the rope in a real fall would be such to act to try and correct his initial mistake by trying to pulltheneck back over the improperly tied Yosemite finish.

Still find myself a bit disconcerted about this though. I always dress and set my knots, but lots of people don't.
stefanfischer on 16 Jul 2012 - host-62-245-219-245.customer.m-online.net
In reply to PeteH:
> ... but if you tighten it up properly it looks like a completely different knot.

It does look a little bit different - but not by much. Anyway, how come the knot changes according to how you tighten it? I know of no other knot that does that. You can play for hours with the regular bowline, but however you tighten it - it's still a bowline. In fact, in the science of knot-theory 2 knots are the same if you can play with one and reach the other without rethreading. So he basically proved that the Yosemite bowline is a simple figure 8 (not doubled). Now try to prove anything like that with a bowline...

> even if he had tightened it up after having tied it wrongly, there's no way the main load-bearing line could "straighten out" in the way he shows.

I don't see why. If the knot is tight, you just need more force. Like, when falling.

> What I will certainly admit is that this video does demonstrate that it's easy to tie the Yosemite bowline incorrectly.

It just cannot be that a knot is correctly or incorrectly tied based on the way you tighten it, without changing the threading.

> I probably wouldn't teach the Yosemite bowline to someone new to the sport, because a figure-of-eight is easier to get right first time and harder to get wrong.

I fully agree. It stays a figure of 8 even of you tug on the loose end first.

sarahlizzy - on 16 Jul 2012
In reply to stefanfischer:
In fact, in the science of knot-theory 2 knots are the same if you can play with one and reach the other without rethreading. So he basically proved that the Yosemite bowline is a simple figure 8 (not doubled).

That doesn't sound right, you've just "proven" that any loop knot that can be tied without access to the end of the rope (e.g. Bowline ona bight, double dragon, alpine butterfly, figure of eight on the bight. etc.) is the same as no knot at all!
markez on 16 Jul 2012
In reply to stefanfischer: He didn't pass the free end through the nipping loop. I will continue to use the Yosemite. But thanks for posting this rubbish anyway... shows you don't have a clue.

(Perhaps I can rethread a figure of eight through my gear loops and start a new thread "Figure 8 not safe for climbing".)
stefanfischer on 16 Jul 2012 - host-62-245-219-245.customer.m-online.net
In reply to sarahlizzy:

> That doesn't sound right, you've just "proven" that any loop knot that can be tied without access to the end of the rope (e.g. Bowline ona bight, double dragon, alpine butterfly, figure of eight on the bight. etc.) is the same as no knot at all!

lol! That's right! As long as you don't put anything "in" the knot, like your harness, or a carabiner tied to a stand, you actually just have a loop according to the official science - but - as soon as you put something in there that cannot be threaded through the knot, it's no longer a loop.

So it's still safe to use the rethreaded 8 as long as we don't forget to thread it through the harness ;)

Al Randall on 16 Jul 2012
In reply to stefanfischer: The fact that this vid. has prompted so much discussion suggests to me that there may be an issue with this knot. This is a good thing. The very fact that it can be manipulated in a variety of ways with the consequent number of results is in it's self worrying. This is a bad thing. I have for some time considered adopting the Yosemite Bowline but I think I will stick with my standard bowline with a double stopper knot to finish.

Al
sarahlizzy - on 16 Jul 2012
In reply to stefanfischer:

Thinking about this a bit more,what he's doing is capsizing the knot while tying it. The knot can't capsize in this fashion in use because it requires a pull on the free end, which won't occur - its never load bearing.

It's concerning that a capsized Yosemite bowline looks superficially like an uncapsized one, and perhaps this could happenwhenone is tired or not paying attention while tying the knot (although part of my routine for tying this knot is to set the online before performing the Yosemite tuck).

Perhaps I will investigate the use of a different knot.
sarahlizzy - on 16 Jul 2012
In reply to stefanfischer:
> (In reply to sarahlizzy)
>
> [...]
>
> lol! That's right! As long as you don't put anything "in" the knot, like your harness, or a carabiner tied to a stand, you actually just have a loop according to the official science - but - as soon as you put something in there that cannot be threaded through the knot, it's no longer a loop.

I put it to you that this is trivially wrong. Tie an alpine butterfly and then load both ends without putting anything in the loop. I'd wager the rope will break before it will revert to its unknotted state.

highclimber - on 16 Jul 2012
In reply to Al Randall: I agree that a discussion is not necessarily a bad thing but this video misrepresents the knot as some kind of death knot when in reality any knot can be tied incorrectly to a point it becomes dangerous.
stefanfischer on 16 Jul 2012 - host-62-245-219-245.customer.m-online.net
In reply to markez:
> ... He didn't pass the free end through the nipping loop.

of course he didn't - Why would he?
The Yosemite finish doesn't call for that:

http://en.wikipedia.org/wiki/Yosemite_bowline

Passing the free end again through the nipping loop will untie it even further, wouldn't it?

stefanfischer on 16 Jul 2012 - host-62-245-219-245.customer.m-online.net
In reply to sarahlizzy:
> Tie an alpine butterfly and then load both ends without putting anything in the loop. I'd wager the rope will break before it will revert to its unknotted state.

You're right. But theoretically speaking, with a strong enough rope you will open this knot into a straight line with enough force and no re-threading.

This is an interesting theory, but still just a theory - not practice. The dangerous thing about the yosemite is not its turning into a figure 8.
It's the fact that you can lose the bowline even when you thread everything correctly.

sarahlizzy - on 16 Jul 2012
In reply to stefanfischer:
> (In reply to sarahlizzy)
> [...]
>
> You're right. But theoretically speaking, with a strong enough rope you will open this knot into a straight line with enough force and no re-threading.

I'm not a topologist, but I suspect that' not actually true. Consider bends - it's possible to make bends that tighten when pulled. Most bends can also be made into a loop knot.

Your point is getting dangerously close to "manipulate a knot sufficiently and you can untie it". We already know that!
CurlyStevo - on 16 Jul 2012
In reply to markez:
> (In reply to stefanfischer) He didn't pass the free end through the nipping loop. I will continue to use the Yosemite. But thanks for posting this rubbish anyway... shows you don't have a clue.
>
> (Perhaps I can rethread a figure of eight through my gear loops and start a new thread "Figure 8 not safe for climbing".)

I may be being a bit thick here but I think he tied a yosemtie bowline in all cases. can you explain which step he did wrong.

it may be usefull to refer to these pictures...
http://en.wikipedia.org/wiki/File:YosemitebowlineBulin1_5.jpg
highclimber - on 16 Jul 2012
In reply to CurlyStevo: in the second instance, the bowline wasn't tightened and he pulled the finish before setting the knot. this pulled the finish back through the hitch. You would never do this usually hence the contention!
sarahlizzy - on 16 Jul 2012
In reply to CurlyStevo:
> (In reply to markez)
> [...]
>
> I may be being a bit thick here but I think he tied a yosemtie bowline in all cases. can you explain which step he did wrong.

Watch carefully the second time. He passes the workingendround the back of the leg and then round the front, as normal, creating a second "loop" underneath the nipping loop.

What he then does, however, is passes this through through the neck and pulls that loop underneath th nipping loop, undoing the bowline in the process.

The Yosemite finish is a tuck to be applied to a bowline that has finished being tied. Before starting it, make sure the nipping loop is tight and the failure mode demonstrated can't occur.

CurlyStevo - on 16 Jul 2012
In reply to sarahlizzy:
I've checked again and I can't see anything wrong with the way it was tied.
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highclimber - on 16 Jul 2012
In reply to CurlyStevo:
> (In reply to sarahlizzy)
> I've checked again and I can't see anything wrong with the way it was tied.

This is the crux. there was nothing wrong with the way it was tied. it's the way it was set that's the issue.
CurlyStevo - on 16 Jul 2012
In reply to highclimber:
> (In reply to CurlyStevo) in the second instance, the bowline wasn't tightened and he pulled the finish before setting the knot. this pulled the finish back through the hitch. You would never do this usually hence the contention!

Yes I understood that much, however some people are saying the knot was incorrectly tied. Unless I'm missing something I think that is stretching the definition somewhat as I can't see anything wrong with the way it was tied other than it was tightened from the loose end and the knot was quite loose when he did this.
markez on 16 Jul 2012
In reply to CurlyStevo: Alright, I saw this as imflammatory, saw something in the video and replied too quickly... I see the Yosemite doesn't go through the nipping loop. (I've been rethreading the nipping loop on my bowline finishes lately). Thanks for correcting me.
highclimber - on 16 Jul 2012
In reply to CurlyStevo: I don't agree that it was tied incorrectly in either instance. it was just the way he pulled it tight that changed
sarahlizzy - on 16 Jul 2012
In reply to CurlyStevo:
> (In reply to sarahlizzy)
> I've checked again and I can't see anything wrong with the way it was tied.

If you loosely arrange a load of rope roughly in the shape of a knot and pull one of the ends, what you end up with might not be what you were hoping for. Setting knots is part of tying them, not an afterthought.
speekingleesh - on 16 Jul 2012
In reply to sarahlizzy:
>
> I'm not a topologist, but I suspect that' not actually true. Consider bends - it's possible to make bends that tighten when pulled. Most bends can also be made into a loop knot.

Yes but all that happens when they tighten is that the friction holding the knot together increases (towards some limiting value). Given an infinity strong rope you would eventually overcome the friction and the knot would come apart.

As you say though this fact doesn't really show you anything new...
CurlyStevo - on 16 Jul 2012
In reply to sarahlizzy:
Rather a spurios argument IMO. Unless I'm missing something the knot was tied correctly and wasn't "roughly in shape of a knot", something some people including yourself were disupting.

Can you explain what you meant here or do you accept this wasn't correct now?

"Watch carefully the second time. He passes the workingendround the back of the leg and then round the front, as normal, creating a second "loop" underneath the nipping loop."

I agree it was tightened in a rather unusual manner but still what other knot do you know that we use for such a critical purpose as tieing on to the rope that when tied correctly and then tightened can move in to a form of the knot which is potentially not as safe?

sarahlizzy - on 16 Jul 2012
In reply to CurlyStevo:

It wasn't tied correctly. I reiterate - setting a knot is part of tying it.
CurlyStevo - on 16 Jul 2012
In reply to sarahlizzy:
OK it doesn't really matter, I'm not actually arguing that knots shouldn't be dressed and set, just to get this straight the knot was tied correcly up to the point it was tightened, we are all in agreence with that much right?
needvert on 16 Jul 2012
In reply to speekingleesh:
> (In reply to sarahlizzy)
> [...]
>
> Yes but all that happens when they tighten is that the friction holding the knot together increases (towards some limiting value). Given an infinity strong rope you would eventually overcome the friction and the knot would come apart.
>
> As you say though this fact doesn't really show you anything new...

The most common model for friction that I've seen is uN=Friction. With an infinitely strong material does this assertion of some limiting value for friction hold?
I'd have expected friction to approach infinity too.

highclimber - on 16 Jul 2012
In reply to CurlyStevo: That's what I agree with. don't know about anyone else!?
Hephaestus - on 16 Jul 2012
In reply to CurlyStevo: Not really, because he lays out the knot and then totally subverts its integrity before tightening it in such a contrived way that it looked to me as though it would never happen practically.

I untie an edwards bowline using the technique he uses to 'tie' the yosemite variant (although at the other end of the knot).

If you're all going to take this thread seriously I'll be back on tomorrow with a series of videos to show how how not tying every other knot in common usage is dangerous. It'll drastically cut down on the mass rush to the crags if the weather ever gets better if everyone on UKC develops a mistrust of their knots!
CurlyStevo - on 16 Jul 2012
In reply to Hephaestus:
"and then totally subverts its integrity"

Actually he doesn't do this the second time the knot is tied, he ties the yosemetie bowline correctly but quite loosely and then tightens it from the free end.
CurlyStevo - on 16 Jul 2012
In reply to Hephaestus:
for the record I'm not suggesting people now treat the knot as dangerous that decision is up to them.
Hephaestus - on 16 Jul 2012
In reply to CurlyStevo: and I don't understand how I could do this practically.

Look out for the "Greek blacksmith in death-plunge bowline balls up" next week, but it just looks like scaremongering.
stefanfischer on 16 Jul 2012 - host-62-245-219-245.customer.m-online.net
In reply to Hephaestus:
> ... tightening it in such a contrived way that it looked to me as though it would never happen practically.

Well, I managed to do it. Without even trying, at first. Pulled both the loose end and the main rope together, and flop - it happened.

> If you're all going to take this thread seriously I'll be back on tomorrow with a series of videos to show how how not tying every other knot in common usage is dangerous.

Please show us any other tie-in knot, (double bowline, double figure 8, whatever), and how you tighten it (Without re-threading anything!) and destroy something in the process. I tried for a really long time with the simple bowline - couldn't do it.

stefanfischer on 16 Jul 2012 - host-62-245-219-245.customer.m-online.net
In reply to needvert:

> The most common model for friction that I've seen is uN=Friction. With an infinitely strong material does this assertion of some limiting value for friction hold?
> I'd have expected friction to approach infinity too.

For the sake of the theoretical knot-discussion:

Take "u" to 0, and there you have it.
The rope doesn't need to be infinitely strong - it needs to be infinitely smooth, so that the friction in minimal. In that (impractical) case, you could pull on the perfect Yosemite bowline in such a way that you get the simple figure-of-8 without rethreading.

speekingleesh - on 16 Jul 2012
In reply to needvert:
>
> The most common model for friction that I've seen is uN=Friction. With an infinitely strong material does this assertion of some limiting value for friction hold?
> I'd have expected friction to approach infinity too.

Really? I would expect u F_n = F to breakdown (on the basis that with our "infinitely strong rope" we've defined the bonds within the rope as infinitely strong and, in order to maintain the idea that the rope is forming a knot as opposed just a lump of material, assumed the inter surface bonds must be weaker.)

I guess a more elegant way of making the original point (all bends are equivalent to an unknotted rope) would be to point out that the thing that determine whether a jamming knot will unravel under load or not is the coefficient of friction associated with the rope, not the shape of the knot.
speekingleesh - on 16 Jul 2012
In reply to stefanfischer:
>
> Please show us any other tie-in knot, (double bowline, double figure 8, whatever), and how you tighten it (Without re-threading anything!) and destroy something in the process. I tried for a really long time with the simple bowline - couldn't do it.

Assuming you tie a stopper knot in your re-threaded figure of 8 or bowline then I don't think its possible is it? If you don't tie a stopper knot it's easy, just ring load either whilst they are still loose and they'll both come undone.
In reply to jon:
> (In reply to a lakeland climber)
>
> Yes. If you thread it incorrectly, it isn't a bowline.

If you thread it incorrectly it isn't even a knot!


Chris
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stefanfischer on 16 Jul 2012 - host-62-245-219-245.customer.m-online.net
In reply to speekingleesh:

> just ring load either whilst they are still loose and they'll both come undone.

They become undone once the loose end is pulled back into the knot - this is also some kind of "rethreading".
He originally claimed that he can undo any knot without any kind of rethreading - just like the Yosemite bowline in the video.

Like, do your knot (without fastening), then tie both ends of the rope to 2 trees, and then try to undo the knot. I'd bet you can still convert the Yosemite to a simple 8, but you cannot do anything with any other knot.
andi turner - on 16 Jul 2012
In reply to those people who use the "Yosemite Finish":

Why do you use this knot over a standard figure of eight, bowline or rethreaded bowline? Is it just to be snazzy?

I can completely understand the reasoning behind the Figure of Eight, Bowline and rethreaded one, I use them all at some point, but can't see why I'd ever use that "yosemite finish", even more so after seeing the failings f the knot.

I like a knot which i can't get wrong, when I'm wet, cold and tired and just want to get off the crag. I like a knot which works well whatever rope I use, whether it's old, new, frozen, skinny or whatever. I like a knot which my friend, the guy "floor walking" at the wall or some random climber passing by or sharing a belay can easily recognise.

If you can give me one good reason to use the 'yosemite finish' please enlighten me, and don't you dare say it's quicker!
rgold - on 16 Jul 2012
In reply to stefanfischer:

First of all, thanks for this very interesting observation. To some extent, you are suffering from hostility typically lavished on bearers of bad news, no matter how accurate or appropriate the news is.

Some of the arguments seem to have devolved into semantics, namely whether or not a knot has been "incorrectly" tied if it is tied in a topologically equivalent way. Knot theory is an extensive and beautiful area of mathematics, but it does not address real-world properties of knots such as strength and stability. The whole point of your observation is that topologically equivalent knots may not have the identical properties from a climber's point of view. To argue, under those circumstances, that two topologically equivalent ways of tying a knot are both "correct" and that the knot itself is therefore "dangerous" is a stretch, since the "worse" result is not equivalent to the bowline in real-world terms and can be avoided by utilizing an appropriate tying procedure.

I think the video pushes "topology over reality" even further by collapsing a very loose knot into something, which, after further manipulation, is seen to be "untied." There is nothing new about this sort of thing at all. The ordinary bowline, if tied loosely, can be collapsed into a slip knot with the rope end simply threaded through the loop, surely as bad an outcome as the one in the video. Yet this topologically equivalent configuration is not held against the bowline, and is in fact promoted by some as a method of tying it!

Meanwhile, the heat of battle being what it is, the important and interesting question isn't being addressed. Suppose we tie the bowline with Yosemite finish the "wrong" way but dress it and tighten it with the same care we'd use with any other climbing knot. Then the real question is about the properties that version of the knot has, understanding that, just as with the ordinary bowline, those properties could be quite different from what happens when a loose version is collapsed into something catastrophic.

So we need tests. (Jim? Are you out there?) Until such tests, it is premature to say that the "wrong" version of the bowline with Yosemite finish is in some sense "untied." Of course, prudence would suggest we take the assertion to be true until we have more decisive information.

Bowlines have their uses, but have been taking quite a beating recently. (For example, the fatality in a U.K. gym blamed on a bowline untying in spite of the fact that there were no witnesses who ever saw the bowline used and it was just as likely that no knot at all had been in place.)

Up until now, I've thought that the real problems one hears about have occurred when ordinary bowlines were not given any finishing treatment---a bowline tied without some additional finish should not be considered a climbing tie-in knot. But now we know that at the Yosemite finish, if manipulated incorrectly---something that is easy to avoid---can lead to a configuration of unknown strength and reliability. I think everyone ought to thank you for that.

A final remark on checking the knot. As you are tightening a bowline with Yosemite finish, the knot has two turns around the loop that goes through the harness tie-in points. When you tug on the standing part of the rope (the part that leads from you ultimately to your partner), it will tighten one of those two loops. If it tightens the closest loop to you, then you have managed to tie the "wrong" version. If it tightens the further loop (or put another way, if you have to tug on the bitter end to tighten the closest loop), then you have the standard version in place.

crossdressingrodney - on 16 Jul 2012
In reply to stefanfischer:

Thanks for posting that Stefan. I have used that knot before, believing it to be a sensible way of finishing off a bowline, and I'm very grateful for the video.

Sarah might be quite happy making sure she pulls on the ropes in the right order (I believe you can retrieve your rope after a full-length abseil, Bear Grylls style, if you don't mind doing that) but I like to have topology on my side!
crossdressingrodney - on 16 Jul 2012
In reply to rgold:

Thanks for that too. That's a fair point about how the bow line can be deformed into a slip knot - although non-scientific experimentation with my shoelaces suggests it's a less scary-looking type of slip knot (...?)

Now that you mention it, it's clear that any way of tying in to the end of a rope is topologically equivalent to a slip knot.
jkarran - on 16 Jul 2012
In reply to PeteH:

> This is stupid. The only learning point from the video is "Don't half-tie your knot, then fiddle around with it loads, then completely fail to set it before starting to climb." The function of most knots depends on their being properly set, and the behaviour of a loose knot which has not been set bears little relation to the finished form of a knot.

Not really fair. If you tie a sloppy loose fig8, overhand or bowline then fall onto it it will, subject to having a bit of a tail or a stopper sort itself out into a half decent knot.

The Yosemite bowline isn't a knot I use, I guess because I never saw the point but I have in the past spent a few moments learning to tie one out of curiosity. After a couple of successful attempts I had one fall apart in my hands just like in that video. I figured I'd cocked it up but seeing as it wasn't obvious how I sacked off any further experimentation figuring I'd cock it up again for real if I got into the habit of using it. I think perhaps I didn't cock it up after all.
Oceanrower - on 16 Jul 2012
In reply to sarahlizzy:
> (In reply to stefanfischer)
>
> perhaps I will investigate using the rethreaded bowline on a bight in future.

At the risk of continuing a discussion from a previous thread, I would still like someone to explain to me how on earth you can rethread a bowline on the bight. You'll end up with four strands of rope. A bit bulky surely.

highclimber - on 16 Jul 2012
In reply to stefanfischer: The video has made me think about it a bit more than I have done previously but I don't think it would make me question my use of it.

To answer Andy Turner's question, I think its as safe as a regular bowline (subject to any real drop tests that may come in light of this discussion). I place a stopper on mine and it is easier to tie and easier to keep an eye on it.

rgold - on 16 Jul 2012
In reply to Oceanrower:

Its a bowline on a bight. But you tie it in a rethreaded fashion so that it can be threaded through the harness tie-in points. The distinction is analogous to the figure-8 tie in and the figure-8 loop tied on a bight.

Being a bowline on a bight when it's all done, it does have two loops, not one (but not four either), through the tie-in points.
andi turner - on 16 Jul 2012
In reply to Oceanrower:

This is what I do....

You have the middle of the rope, in a bight.

Thread that through your harness as though you are beginning a bowline.

Go as far as "the rabbit comes out of the burrow", but instead of going around the tree, take the bight and pass it over your head and down your back like a skipping rope, when it comes back round you should have what you're after...
andi turner - on 16 Jul 2012
In reply to highclimber:

So, why do you do a yoesmite finish and then a standard finish? what is the benefit over the standard bowline? Seems a waste of time and just makes the knot more difficult to recognise?
Mr Lopez - on 16 Jul 2012
In reply to stefanfischer:
> (In reply to Hephaestus)
> [...]

> I tried for a really long time with the simple bowline - couldn't do it.

Try pulling the loop sideways...
highclimber - on 16 Jul 2012
In reply to andi turner: why does it matter that its difficult to recognise? I don't go to indoor climbing walls anymore and anyone I climb with knows what it is.

'why do you do a yoesmite finish and then a standard finish?'

I use a stopper with it as I think any knot you use to tie in with SHOULD have a stopper regardless.

it isn't a matter of benefits over other knots but I think it is easier to keep an eye on the stopper than a regular Bowline.
TonyP - on 16 Jul 2012
In reply to andi turner:
> (In reply to Oceanrower)
>
> This is what I do....
>
> You have the middle of the rope, in a bight.
>
> Thread that through your harness as though you are beginning a bowline.
>
> Go as far as "the rabbit comes out of the burrow", but instead of going around the tree, take the bight and pass it over your head and down your back like a skipping rope, when it comes back round you should have what you're after...

tempted to try it lol
sarahlizzy - on 16 Jul 2012
In reply to crossdressingrodney:
> (In reply to stefanfischer)
>
> Thanks for posting that Stefan. I have used that knot before, believing it to be a sensible way of finishing off a bowline, and I'm very grateful for the video.
>
> Sarah might be quite happy making sure she pulls on the ropes in the right order

It's not even that. I set the bowline before applying the Yosemite finish, and I make sure it goes round the back of the other leg as well.

Furthermore, if you make the mistake in the video, and then set what you're left with, it very obviously fails visual inspection - this wasn't done in the video.

jimtitt - on 16 Jul 2012
In reply to rgold:
> (In reply to stefanfischer)
>


> Meanwhile, the heat of battle being what it is, the important and interesting question isn't being addressed. Suppose we tie the bowline with Yosemite finish the "wrong" way but dress it and tighten it with the same care we'd use with any other climbing knot. Then the real question is about the properties that version of the knot has, understanding that, just as with the ordinary bowline, those properties could be quite different from what happens when a loose version is collapsed into something catastrophic.
>
> So we need tests. (Jim? Are you out there?) Until such tests, it is premature to say that the "wrong" version of the bowline with Yosemite finish is in some sense "untied." Of course, prudence would suggest we take the assertion to be true until we have more decisive information.
>

Tied with the Yosemite finish loop pulled up through and tightened and with the original bowline loop slack the knot locks up and continues to tighten. I stopped at 6kN as that is all I´m set up for at the moment. There appears no possibility that the tensioned rope will straighten as it has formed a half hitch around two other parts.

Another point worth raising is the implication is that if this rope straigtening did occur then the end result which is the live rope through an 8 would catastrophically fail. Under load it actually snugs down nicely and incoporates the tape loop into an overhand with an additional girth hitch around the tape. I also stopped testing this at 6kN.
stefanfischer on 16 Jul 2012 - dslb-094-218-195-186.pools.arcor-ip.net
In reply to rgold:

Thanks, you summarized my thoughts perfectly. The topology "game" was just a side note. My real concern is getting a knot I don't know, which seems (to me) much weaker than a bowline. Not only under load, but I'm worried about its properties under changing loads. (If the loose end somehow backs up, you don't have any knot anymore).
CurlyStevo - on 16 Jul 2012
In reply to jimtitt:
I saw a (you tube ?) video recently that showed various loop tie in knots being pulled apart (as could occur when you belay from the tie in or attach to anchors at belays). The figure of eight and bowline with a hitch stopper knot (rather than a full stopper knot) was significantly stronger than the tuck the tail variants and no stopper knot. (I don't suppose you have a link to it I can't find it again now)
andi turner - on 16 Jul 2012
In reply to highclimber:
> (In reply to andi turner) why does it matter that its difficult to recognise? I don't go to indoor climbing walls anymore and anyone I climb with knows what it is.
>

Fair enough, and I know that it's probably just fine, BUT, the day may come that you're sharing a belay with me, or about to set off up a route in the vicinity of someone else who casually glances over. The knot is unfamiliar and as such I/they say nothing, yet you've tied it wrong. You don't need to be in a climbing wall to have people looking out for you.

I don't understand why you would choose a knot with any misgivings when a figure of eight is so superior? If you tie a figure of eight incorrectly, then it looks clearly wrong and usually just means you've tied a double overhand. Why complicate matters?

If it's not safer (fig 8), then the next thing in the heirachy may be 'easier to untie' (bowline) after that, then what's the point?
highclimber - on 16 Jul 2012
In reply to andi turner:

> I don't understand why you would choose a knot with any misgivings

I have yet to see any real evidence that it has any misgivings over a regular bowline.
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jimtitt - on 16 Jul 2012
In reply to stefanfischer:
If you pull the Yosemite loop up through but then leave it slack you still end up with a half-hitch in the bottom of an 8 with the spare end trapped by the top of the 8 which appears to be perfectly stable.
If you take the spare end back out of the top loop you get two opposed half hitches like a clove hitch around the rope strands themselves (there is a name for this which I can´t remember). This looks like it might roll through but hard to tell without pull testing it, testing knots which have already been incorrectly tied/dressed and then started to fall apart seems going a bit far!
jimtitt - on 16 Jul 2012
In reply to CurlyStevo:
No idea I´m afraid, I use a re-threaded bowline which is stronger anyway if ring-loading is a criteria.
Mr Lopez - on 16 Jul 2012
In reply to jimtitt:
> (In reply to stefanfischer)
> you get two opposed half hitches like a clove hitch around the rope strands themselves (there is a name for this which I can´t remember).

Sheepshank?

mockerkin on 16 Jul 2012
In reply to stefanfischer:

>> This doesn't help much either, because this thread has gone technical.
www.animatedknots.com
andi turner - on 16 Jul 2012
In reply to highclimber:
> (In reply to andi turner)
>
> [...]
>
> I have yet to see any real evidence that it has any misgivings over a regular bowline.

So use a regular bowline?
crossdressingrodney - on 16 Jul 2012
In reply to sarahlizzy:
> It's not even that. I set the bowline before applying the Yosemite finish, ...

By 'set the knot' do you mean 'pull it tight'? Just to check I understand you? You can't pull it completely tight if you're leaving room for the finish, surely?

> ... and I make sure it goes round the back of the other leg as well.

I thought that we agreed that everyone on here and in the video is tying the same knot, topologically speaking, and the only difference is in the setting and dressing? Are you saying that you are tying a topologically different knot to the one in the video?

> Furthermore, if you make the mistake in the video, and then set what you're left with, it very obviously fails visual inspection - this wasn't done in the video.

The 'mistake' in the video, as I understand it, is not supposed to illustrate an error you might make when tying in but rather what could happen if your knot loosens and move around a little, before being fell on. So the problem is that a perfectly good knot passes the original visual inspection but then later fails.
highclimber - on 16 Jul 2012
In reply to andi turner:
> (In reply to highclimber)
> [...]
>
> Fair enough, and I know that it's probably just fine, BUT, the day may come that you're sharing a belay with me, or about to set off up a route in the vicinity of someone else who casually glances over. The knot is unfamiliar and as such I/they say nothing, yet you've tied it wrong. You don't need to be in a climbing wall to have people looking out for you.
>
>

I have found the opposite. People who are unfamiliar with it generally ask me what I am tying and I am more than happy to explain to them, this has the added advantage of drawing my attention to tying it properly.

andi turner - on 16 Jul 2012
In reply to highclimber:
> (In reply to andi turner)
> [...]
>
> I have found the opposite. People who are unfamiliar with it generally ask me what I am tying and I am more than happy to explain to them, this has the added advantage of drawing my attention to tying it properly.

Fair enough, I'll look out for you and ask you when I see you. In preparation, the questions will go a little like this:

Q: "Hey, that's a fancy knot! Why not just a figure of eight?"

A: "I'm projecting this route and expect to fall a lot, so I need a knot that's easy to untie so I don't waste any calories undoing those pesky eights!"

Q: "Cool! Why not just a normal bowline then?"

A: "Well, because the knot is a little 'underground' I get a load of people asking me why I use the knot, and that makes me extra vigilant...not that I like climbing around other people very often."

Q: "But I saw a video once on UKC that showed that if it wasn't tied perfectly, that it could come undone?"

A: "Listen pal.... has anyone ever told you how dangerous it is to talk to someone when they're tying on?"

Q: "Hmm, yeah, good point, sorry....hope you tied it right...bye...good luck on the project. Sorry."

;o)

highclimber - on 16 Jul 2012
In reply to andi turner: your fictious dialogue seems to imply that I am a complete nobber who talks to people like a douche before coming across as an utter rude bastard by asking them not to speak to me!

brilliant, though you should read my above comments about why I use the Y. bowline.
sarahlizzy - on 16 Jul 2012
In reply to crossdressingrodney:
> (In reply to sarahlizzy)
> [...]
>
> By 'set the knot' do you mean 'pull it tight'? Just to check I understand you? You can't pull it completely tight if you're leaving room for the finish, surely?

I pull the knot tight, yes. In my experience, this generally still leaves enough room to perform the final tuck because of the stiffness of the rope. Even of not, it'll push through with a little effort. Remember, a Yosemite finish is a tuck *after* the bowline has been tied.

> I thought that we agreed that everyone on here and in the video is tying the same knot, topologically speaking, and the only difference is in the setting and dressing? Are you saying that you are tying a topologically different knot to the one in the video?

No. It's topologically the same, but the working end comes up on the other side of the standing end, which makes for a tidier knot and places part of the "collar" in the way of the Yosemite loop coming up through it. Try it and see.

This was the way I learned to tie the Yosemite finish: under the adjacent leg, over it, under the other leg and then up through the neck. The way it's tied in the video is a shortcut which I would regard as sloppy.

> The 'mistake' in the video, as I understand it, is not supposed to illustrate an error you might make when tying in but rather what could happen if your knot loosens and move around a little, before being fell on. So the problem is that a perfectly good knot passes the original visual inspection but then later fails.

The whole point of the Yosemite finish is that the extra friction prevents this loosening, which is a failure of the standard bowline. This applies even moreso if one ties a grapevine stopper above the Yosemite finish, which is my standard single pitch sport tie-in knot (for trad and multipitch I generally use a fig 8).
rgold - on 16 Jul 2012
In reply to sarahlizzy:

I've used the Yosemite finish, together with a grapevine (barrel) stopper knot, for more years than many of you have been alive. It isn't new and it has little or nothing to do with Yosemite. Stefan's point about how the knot can transform to something else is something no one I knew ever suspected, and we should all thank him for bringing it to light.

That said, Jim's test does suggest that there may not be anything the matter with the transformed version, and in particular it doesn't seem to be in any functional sense "untied." Folks are nattering on in spite of this observation, which would make the entire discussion genuinely moot. It would be better if the knot could be tested to 12 kN and also its ring-loading behavior checked.

Many years ago I took a long nasty fall with a figure-8 tie in. It took two of us about twenty minutes to get it untied, and that was the last time I used a figure-8 (I started out with and used a bowline for years previously).

Some people have asked why use the Yosemite finish. I started using it when I switched over to belaying off the rope loop rather than the harness loop. With the belay device clipped to the rope loop, having the stopper knot in there is awkward and everything is cleaner with the Yosemite finish and the stopper knot outside the rope loop. This set-up also seemed to me to offer enhanced resistance to any ring-loading failures, which have to be considered if you are belaying off the rope loop.
andi turner - on 16 Jul 2012
In reply to highclimber:

Hey, I hope you take it in good humour, as it was intended. Genuinly, I have no problem with people using any knot they choose so long as they tie it correctly. The world seems to have three types of people: figure of eight folk, Bowliners, and the others.

I've taken lots and lots of falls over the past two decades! I've never had a real issue undoing a figure of eight. I heard about one person who got distracted tying into one once, and only pulled it through the first loop when re-threading, he fell off Lourdes, as opposed to taking a rest, which caused the rope to cinch up tight saving his life. That's the only time I've heard of a fig of eight cock up. I've heard of two fatalities and one nasty, nasty fall as a result of bowlines (the guy who survived had been using them for over 40 years, he said afterwards that he'd never use nor recommend one again), that's enough for me to treat them with caution.

I want a knot to be safe, as foolproof as possible and not come undone. These are more important to me than a knot which unties easily after falls.
highclimber - on 16 Jul 2012
In reply to andi turner:
> (In reply to highclimber)
>
> Hey, I hope you take it in good humour, as it was intended.
Yes, I did. i'm no where near as sensitive as some people on here!
alan1234 - on 17 Jul 2012
I met a climber a few years ago who, when leading a big wall pitch in South Africa back in the 80s, had his lead rope whistle away. He had used a bowline with a double stopper and theorised that the stopper had rubbed against the rock and come undone, exposing a naked bowline which then inverted. 'Fortunately' he had a haul line and instructed his partner to start belaying him on that instead!
Oceanrower - on 17 Jul 2012
In reply to andi turner:
> (In reply to Oceanrower)
>
> This is what I do....
>
> You have the middle of the rope, in a bight.
>
> Thread that through your harness as though you are beginning a bowline.
>
> Go as far as "the rabbit comes out of the burrow", but instead of going around the tree, take the bight and pass it over your head and down your back like a skipping rope, when it comes back round you should have what you're after...

I may be being particularly dense here but I have absolutely no idea what you are on about.
deepsoup - on 17 Jul 2012
In reply to Oceanrower:
> I would still like someone to explain to me how on earth you can rethread a bowline on the bight. You'll end up with four strands of rope. A bit bulky surely.

On the offchance that you're not trolling, I'll try again:
You don't rethread a bowline on the bight - you tie an ordinary bowline and then rethread to end up with a bowline on the bight.

(Which I'd assumed you were insisting is not actually a bowline on the bight merely because a) it isn't tied on a bight and b) you were being a smartarse. Apologies if the latter was not actually the case.)
deepsoup - on 17 Jul 2012
In reply to Oceanrower:
> I may be being particularly dense here but I have absolutely no idea what you are on about.

He's describing how you would tie into the middle of a rope with a bowline on the bight - for example to lead or second a short route with a long half-rope.
sarahlizzy - on 17 Jul 2012
In reply to Oceanrower:
> (In reply to andi turner)
> [...]
>
> I may be being particularly dense here but I have absolutely no idea what you are on about.

The bit in green - you have to pass your entire body through it.

http://www.sarahlizzy.com/BowlineBight.jpg
jimtitt - on 17 Jul 2012
In reply to rgold:

Another part of my life wasted!

The first critical point is that for the knot to collapse is that the loaded strand has to straighten and no longer form a hitch. This can only occur if the knot is loosely dressed as otherwise the `around the tree´ loop prevents this. By loosely dressed I mean there is visible slack in the upper bend, this is looser than I would normally tighten a knot and I´m not a fanatic about correctly dressing knots at the best of times.

If we tie the knot loose (and incorrectly dressed naturally)it collapses to the aptly named `mess´ as shown in the video. As one keeps pulling this turns into a curious form of Prusik type knot around the loaded strand. On the rope I was testing with (9mm half rope) this slid at 2.3kN down to the tape loop (two layers 16mm nylon). When it hits the tape it remains as it is and continues to tighten as a slip knot which eventually failed at 9.4kN which seems quite an reasonable value for a somewhat older rope of this diameter. I tested a standard bowline with stopper to give a baseline and this failed at 7.9kN so one can reasonably say that the collapsed Yosemite version appears to be stronger than a normal bowline.

At no stage does there seem any potential for the mess to change into an 8 and this in fact seems impossible without loosening and manipulating the knot. As mentioned earlier in the thread this also seemed a perfectly adequate knot anyway.

Ring pulled there seems no difference between the two ways (the correctly dressed Yosemite and the loop pulled up through variant) as they broke at 19.8kN and 20.1kN respectively. The tape is starting to cut at this point as well.

If by some curious mischance you tie your Yosemite bowline, pull the loop up through and then the spare end falls out of the last tuck you revert naturally enough to a normal bowline.
PeteH - on 17 Jul 2012
In reply to jimtitt:

Jim: may I thank you sincerely and enormously for "wasting" another part of your life in delivering some genuinely useful answers to bring this whole debate to an actual useful conclusion!

> The first critical point is that for the knot to collapse is that the loaded strand has to straighten and no longer form a hitch. This can only occur if the knot is loosely dressed as otherwise the `around the tree´ loop prevents this. By loosely dressed I mean there is visible slack in the upper bend, this is looser than I would normally tighten a knot and I´m not a fanatic about correctly dressing knots at the best of times.


To the OP: This is exactly what I was talking about - in the bit in the video where the guy says "Let's simplify this a little" he's actually rearranging the knot in a way that cannot happen in a real-life loading situation if your knot is properly dressed.


> If we tie the knot loose (and incorrectly dressed naturally)it collapses to the aptly named `mess´ as shown in the video. As one keeps pulling this turns into a curious form of Prusik type knot around the loaded strand. On the rope I was testing with (9mm half rope) this slid at 2.3kN down to the tape loop (two layers 16mm nylon). When it hits the tape it remains as it is and continues to tighten as a slip knot which eventually failed at 9.4kN which seems quite an reasonable value for a somewhat older rope of this diameter. I tested a standard bowline with stopper to give a baseline and this failed at 7.9kN so one can reasonably say that the collapsed Yosemite version appears to be stronger than a normal bowline.

Hooray! I was prompted to convert to the Yosemite bowline for sport after spending 20 minutes trying to untie a nicely welded figure-8 after a large whipper, while the chap next to me who'd used a bowline for his equally large whipper was starting his next climb. At that time I looked up various knot tests for the standard bowline, the Yosemite bowline and the figure-8, and also the Cowboy bowline (a common way of mis-tying the bowline) and they all failed at acceptable loads. Good to know that even if I manage to tie my knot like the chap in this video, I've still got a knot that will hold me.

Pete.
stefanfischer on 17 Jul 2012 - host-62-245-219-245.customer.m-online.net
In reply to jimtitt:

cool, Jim, thanks for testing. I guess all the versions of the Yosemite finish will stop a fall.

> If by some curious mischance you tie your Yosemite bowline, pull the loop up through and then the spare end falls out of the last tuck you revert naturally enough to a normal bowline.

This I didn't really get - when you tighten the Yosemite wrong, you open the bowline. Then, is the spare end falls out of the last tack, as in the video (second tightening of the knot there), aren't you left with no knot? In fact, I tried it out - I've set the Yosemite wrong, pulled the free end out again, and then tightened and pulled on the thing that was left, and it rolled loose like the thief's knot:

http://en.wikipedia.org/wiki/Thief_knot

Hephaestus - on 17 Jul 2012
In reply to jimtitt:

Thanks for making the effort on this, Jim.
krikoman - on 17 Jul 2012
In reply to stefanfischer: Read a lot but not all of the points above.

but to me isn't the fact that it looks like a properly tied knot the whole point.

I understand the preference for the Bowline, yosemite or not, but the fact is they can be tied incorrectly and look OK. The figure of eight looks wrong, if it is wrong.

People can use what they like, it's their life after all, but why have a go at the OP? Surely alll information is just that information. you can choose to disregard if you like.
highclimber - on 17 Jul 2012
In reply to krikoman: No body is having a go at the OP. we're having a discussion. apologies to the OP if they feel like some were having a go, myself included, but I weren't and neither were anyone else...I hope!


@Jim - Thanks for your time on empirically testing something that was quickly denigrating into a 'lynch the bowline' thread. hopefully that will be the end of it but I suspect it won't be.
In reply to krikoman:
>
>
> I understand the preference for the Bowline, but the fact is they can be tied incorrectly and look OK. The figure of eight looks wrong, if it is wrong.


That's cobblers!


Chris
jimtitt - on 17 Jul 2012
In reply to stefanfischer:
> (In reply to jimtitt)
>
> cool, Jim, thanks for testing. I guess all the versions of the Yosemite finish will stop a fall.
>
> [...]
>
> This I didn't really get - when you tighten the Yosemite wrong, you open the bowline. Then, is the spare end falls out of the last tack, as in the video (second tightening of the knot there), aren't you left with no knot? In fact, I tried it out - I've set the Yosemite wrong, pulled the free end out again, and then tightened and pulled on the thing that was left, and it rolled loose like the thief's knot:
>
> http://en.wikipedia.org/wiki/Thief_knot

If you pull the spare end out from the last tuck (the `around the tree part of the bowline´) you end up with a bowline with the difference that the around the tree part has a 180° twist in it which actually looks like an excellent way to make a bowline more secure since you trap the spare end twice. If you pull the spare end out from both tucks you end up with the same end result as previously described (and the porogression from what is shown in the video), the knot with no name that looks something like a sheepshank but isn´t really, however this is surely getting a little careless not to say unrealistic since we have to dress the knot wrongly, loosen it and pull the end out from two tucks to get to this point.
prw - on 17 Jul 2012
In reply to PeteH:
Amen to that, and to Jimtitt's replies. Some sensible points about the bowline.

There's nothing wrong with the bowline IMO, just like any other knot if tied correctly. The person in the video does NOT tie the knot correctly the second time around. Sure this post has raised a very good point about tying the knot correctly in the first place but if done so, then Option 2 CANNOT happen in a correctly loaded situation.
I fail to understand some responses about being able to do it. You're obviously not tying the knot correctly or creating a non real-world situation by pulling on both ends of the rope. If you actually load bear the rope between the knot and belayer the knot actually tightens and strengthens in my experience.

I've been using a bowline with yosemite finish for years and never had any problems (and I've take a few falls ! ;-)).
I use a yosemite finish rather than a normal bowline as according to the book of knots that I have, the yosemite finish creates a stronger knot that a normal bowline (before this sets off another thread - I have no confirmation on this - I am going by the information provided).
The reason I use a bowline is that as others have indicated, it is much easier to untie after a fall (hence the need for a stopper knot to prevent the knot opening which can happen when knocked).

I do agree that the yosemite bowline can be more difficult to check by 'sight' by a climbing partner whether it is correct or not, but with experience this becomes less of an issue. All the more reason I always, double check the knot myself (which people should do anyway).

Even though I use the yosemite bowline myself and prefer this to say a figure of 8 and both these knots are accepted by the BMC as fit for purpose in indoor climbing walls, it is a interesting point to note that specific instructors at Plas-Y-Brenin and mountain guides in Italy that I have climbed with in the past would not let me use a bowline, but that the knot needed to be a figure of 8. Perhaps thats a thread for another time though :-).
krikoman - on 17 Jul 2012
In reply to Chris Craggs:
> (In reply to krikoman)
> [...]
>
>
> That's cobblers!
>
>
> Chris

Oh OK then thanks for putting me right.
wivanov - on 17 Jul 2012
In reply to stefanfischer:

Stefanfischer, did you post the video on youtube as "yosemitebowline"?
krikoman - on 17 Jul 2012
In reply to stefanfischer: I might be wrong - but isn't he (the video bloke) saying it's important to tighten the knot in the correct sequence? I looked at it again and as far as I can see the only difference is the way he tightens the knot not the way he's threaded it.

that being the case then there's no comparision with a fig.8 as you can tighten a fig.8 any way you like, pull one, pull the other pull both, as long as it's tight, it's safe.
highclimber - on 17 Jul 2012
In reply to krikoman: if you don't feel confident enough to tie and use a bowline, or it's variations, safely then no one is going to put a gun to your head to make you use one.
Offwidth - on 17 Jul 2012
In reply to highclimber: Yet the bowline knot has a certain cache. Most people by far use it safely but I've seen folk who don't: weaker variants and/or careless stopper use on the basic knot. I'd say if in any doubt at all, use a fiqure 8.
andi turner - on 17 Jul 2012
In reply to Oceanrower: Here, I did a little video for a rethreaded bowline on the bight.

http://www.flickr.com/photos/30536520@N02/7591222168/in/photostream
Mr Lopez - on 17 Jul 2012
In reply to krikoman:

You can't tie a bowline wrong. Give it a try and you'll see.
jimtitt - on 17 Jul 2012
In reply to andi turner:

FFS that isn´t a re-threaded bowline on the (a) bight. It is a simple bowline on a bight.
Oceanrower - on 17 Jul 2012
In reply to andi turner: I thank you for that. Unfortunately, however, and at the risk of belabouring the point, I'm going to have to agree with Mr. Titt here.

However, please could you show me the rest of the video where you attempt to rethread it!

Admittedly Jim and I seem to be in a minority here but (and I apologise for shouting) YOU CANNOT REALISTICALLY REHREAD A BOWLINE ON THE BIGHT!

You can tie a bowline and re-thread it.

You can tie a bowline on the bight.

And, yes, these two will look similar.

But you CANNOT tie a bowline on the bight without ending up with four strands of rope going through a bloody mess!



rgold - on 17 Jul 2012
In reply to Mr Lopez:

Au contraire, it is possible to tie a bowline wrong. If we use the old mnemonic, "the rabbit comes out of the hole, goes around the bush, and then back in the hole," then in forming the bowline there are two ways to form the hole, two directions the rabbit can emerge (up or down), and two bushes the rabbit could circumnavigate (this is where a wrong version can occur). This gives a total of eight possible actions for tying the bowline. Of these eight, two of them result in a correctly tied bowline (counting the standard and so-called Dutch Navy bowlines as both correct) and four of them just fall apart, which is probably what you were thinking, but two of them result in an incorrectly tied bowline resulting from going around the wrong "bush."

Based on this exhaustive but hopefully not exhausting analysis, we might say that a complete nincompoop has a one in four chance of tying an incorrect bowline.
andi turner - on 17 Jul 2012
In reply to jimtitt: Ok. I see your point. I suppose when the knot is finished, the rethreaded bowline only differs from the bowline on the bight by the stopper knot.

I'll change the vids title FFS.
andi turner - on 17 Jul 2012
In reply to Oceanrower:
> (In reply to andi turner)
> You can tie a bowline and re-thread it.
>
> You can tie a bowline on the bight.
>
> And, yes, these two will look similar.
>
> But you CANNOT tie a bowline on the bight without ending up with four strands of rope going through a bloody mess!

Yes, I agree. I see your point. Too many names!

Good job I just use a figure of eight.

Mr Lopez - on 17 Jul 2012
In reply to rgold:

2 bushes? There's only one in mine i'm afraid. Have i been sold the wrong rope?
ads.ukclimbing.com
Oceanrower - on 17 Jul 2012
In reply to Mr Lopez: You can't have too much bush.....
Mr Lopez - on 17 Jul 2012
In reply to Oceanrower:

Just had a flashback from 'scary movie'...
speekingleesh - on 17 Jul 2012
In reply to rgold:
>
> Au contraire, it is possible to tie a bowline wrong. If we use the old mnemonic, "the rabbit comes out of the hole, goes around the bush, and then back in the hole," then in forming the bowline there are two ways to form the hole, two directions the rabbit can emerge (up or down), and two bushes the rabbit could circumnavigate (this is where a wrong version can occur).

Hmmm looking at what you get if you go round the wrong 'bush' you seem to get the correct knot just with the standing end and one of the loop parts swapped. Does anyone know if this is actually as strong as a correctly ties bowline?
a lakeland climber on 17 Jul 2012
In reply to rgold:
> (In reply to Mr Lopez)
>
>
> Based on this exhaustive but hopefully not exhausting analysis, we might say that a complete nincompoop has a one in four chance of tying an incorrect bowline.

Err no, because if you create the initial loop incorrectly then coming out of the hole and round and back in *the wrong way* actually makes a bowline. So you only have 2 out of 4 possibilities to get it wrong.

However. If you do get it wrong then you don't end up with a Bowline - the arrangement of loops and twists simply comes apart with a slight pull. This goes back to what Chris Craggs and I have said - you cannot tie an incorrect Bowline, it's either correct or it isn't even a knot.

Where a Bowline *is* weak is that it does require a stopper knot to ensure that it doesn't flex and come undone, especially with a short tail.

ALC

jon on 17 Jul 2012
In reply to a lakeland climber:
> (In reply to rgold)
> that it does require a stopper knot to ensure that it doesn't flex and come undone

Which I've never found to be a problem.
krikoman - on 17 Jul 2012
In reply to Oceanrower:
> (In reply to Mr Lopez) You can't have too much bush.....

I'm not too sure about that!! You don't want to get lost.

I'm a bushman, from a long line of bushmen, I think, but there's always a limit.
rgold - on 17 Jul 2012
In reply to Mr Lopez:

You may have been sold one of those recalled unibush ropes.

The "two bushes" refer to the standing part of the rope, which is the correct bush, the other part of the half turn that makes the hole. In principle, after emerging from the hole, one could go around either of these strands.

In reply to ALC:

I stand by my exhaustion. You seem to be missing possibilities, and have focused on the wrong "wrong." I never mentioned which way you go around the bush, so there is no wrong way for that in my counting. But I did acknowledge the two possibilities when I said that I was not distinguishing between the standard bowline and the Dutch Navy bowline (also sometimes called "left-handed" bowline). These are precisely what you get from the two choices about which way to go around the bush, when it is the correct bush.

In any case, combinatorics aside, the main point is that it is possible to tie a bowline incorrectly if one puts the bight around the strand from the half turn "hole" that is not the standing part of the rope. Depending on how the hole was formed, this mistake might just fall apart completely, but it is also possible to obtain a knot that looks much like a bowline but has the standing part emerging from the wrong spot.

I wouldn't trust this version for a second, but I won't ask Jim to waste any more of his precious remaining time on earth checking that claim out.
Mr Lopez - on 18 Jul 2012
In reply to rgold:

Rabbit goes out the hole, digs a tunnel from the side and comes back out the same hole...?

If you go round the bush and into the hole before going out the hole, then you run the tail back the same way leaving a loop, you get an incorrectly tied bowline that looks exactly like a 'fig8 on a bight'. Crazy or what? :)

a lakeland climber on 18 Jul 2012
In reply to rgold:

I had to look up Dutch Navy Bowline and it would appear that it is this variant that I have been tying all these years (actually I also use the double Bowline variant as well).

Whenever I've described the Bowline using the "rabbit" method then I've pointed to the standing rope as the tree/bush and no-one has ever thought of mistaking the bight for the bush. If you hold the loop at the cross-over point between thumb and forefinger with the loop towards you then you simply pass the "rabbit" up through the loop, round the tree (with the rope laying on top of your hand) and back down the loop.

ALC
lyckegard - on 19 Jul 2012
In reply to andi turner:

Nice, I add this to my collection of knot that does the same thing just as good as every knot for the same purpose, but a little bit cooler.
knudeNoggin - on 21 Jul 2012
In reply to speekingleesh:
> (In reply to rgold)
> [...]
>
> Hmmm looking at what you get if you go round the wrong 'bush' you seem to get the correct knot just with the standing end and one of the loop parts swapped. Does anyone know if this is actually as strong as a correctly ties bowline?

"strong" is a problematic characteristic, for various reasons.
Let's just say that this eye knot is known as the Eskimo bowline,
and **decent**. Better, for a tie-in knot, is to >>continue<<
from the formation of this knot to THEN go round the *right* "bush"
--yes, to collar both the eye leg and the main line. You'll now have
the two collars, and three diameters stuffed through the central
nipping loop (which might help *strength*).

This also can be done from the common bowline start --i.e.,
the "going round the <other> 'bush'" bit. It's a tactic that was
introduced by Wright & Magowan in 1928 Alpine Journal, where
they had come up with a means for tying into a line, and realized
that it also indicated a way to secure the bowline. --too bad that
presentation didn't seem to gain legs (and yet the "Yosemite"
version did).


- - - -

To the OP, the video shows a potential risk in the tying of
the Yosemite bowline --not entirely unlikely, with some (stiff)
ropes, and the unfortunate method of setting by pulling on
the tail. It's worthwhile that this possibility is brought to light.
Is it likely a problem ? Well, maybe not so much, but note that
the oft'-cited book on rope working, _On Rope_ (1st ed.), has
it's chapter "3 Knots" showing such a mis-dressed YoBowl
writ large on the chapter's cover page!! (I think that the 2nd
ed. didn't repeat the mistake, but am not certain.)

I would NOT want to use this knot for tie-in. If the instability
of the knot resulted in its capsizing into a noose (i.e., the
main line straightening and all the knotting effecting a hitch
around it), the sliding of material when the noose tightened
couldn't be good for the harness! --that would be in dynamic
loading, not the slow-pull testing Jim did.

*kN*
hexcentric - on 21 Jul 2012
In reply to a lakeland climber:
>
> Where a Bowline *is* weak is that it does require a stopper knot to ensure that it doesn't flex and come undone, especially with a short tail.


As a friend of mine found out to his significant alarm while seconding me in Cogne, when his non stopper knotted bowline untied from his harness and headed up the route ahead of him mid pitch! He didn't fall off happily.
knudeNoggin - on 22 Jul 2012
> Here's a video that shows that when you finish up the bowline with the Yosemite finish, you are actually just untying the bowline

Rather, it's possible in mis-setting the knot, to destroy its integrity.
But there is a similar finish --take the tail around the eye leg in the
opposite direction-- that isn't vulnerable to this (mis)behavior.

> The function of most knots depends on their being properly set
> // ... properly set and dressed

Which is seldom explained in detail (or in any way much beyond
the vague advice to "dress and set the knot") in any source!

> Why people don't just use a simple bowline,
> which has been used by generations of climbers
> (and many more generations of sailors) escape me.

It should not escape you : the reason(s) why have been pretty well
discussed (and there are some posts in this thread giving further
testimony) --it can loosen and come untied, w/o some additional
security. Generations of sailors never used rockclimbing / caving
kernmantle ropes.

> To note: it's easy to check whether you have correctly tied the yosemite
> or edwards variants of the bowline by turning the knot over after tying it.

It's a shame that the bowline is typically shown from the perspective
(re which *face*) that it is --it SHOULD be oriented to that "turned over"
face, where more of the workings of the knot are easily seen! Consider
how the sheet bend is commonly presented --from THAT (turned over)
orientation ; the bowline should likewise be presented (and tied) that way.
I.p., the quick-tying method with the twist of the wrist works better
in this turned-over orientation.

>> As long as you don't put anything "in" the knot, like your harness,
>> or a carabiner tied to a stand, you actually just have a loop [rather, "the un-knot"] according
>> to the official science - but - as soon as you put something in there
>> that cannot be threaded through the knot, it's no longer a loop.
>
> I put it to you that this is trivially wrong. Tie an alpine butterfly and then load both ends
> without putting anything in the loop. I'd wager the rope will break before it will revert to its unknotted state.

You might want to stipulate that the material isn't HMPE rope,
then --not sure that that slippery stuff would hold to rupture vs. slipping,
but it might. (E.g., a double bowline can spill materiall around the doubled
rabbit hole and out, collapsing the eye (!!) in such material, in slow-pull loading.)

> Most bends can also be made into a loop knot.

--or all ?! It's a matter of taking a cookie-cutter view of the *knot*
(tangled area) and then specifying how the *ends* connect or not.
(Or, alternatively, of the angle of loading, neverminding whether e.g.
the legs of the "loop knot" actually connect to form an eye ; the behavior
of the knot depends only on their angle of incidence.)

> dangerously close to "manipulate a knot sufficiently and you can untie it".
> We already know that!

Except that one can't (with ends taken away from access) untie some
"knots", such as an overhand or figure eight or bowline. (Interestingly,
one can re-arrange the bowline to be "directional" in the opposite direction.)

> that the friction in minimal. In that (impractical) case,
> you could pull on the perfect Yosemite bowline in such a way
> that you get the simple figure-of-8 without rethreading.

As noted above, the situation of low friction is not entirely impractical :
it is seen in some modern cordage fibres already.
But you couldn't pull on the YoBowl in a normal way and get a fig.8;
you could pull on the two ends, and get an unknotted rope, though!


> On the rope I was testing with (9mm half rope) this slid at 2.3kN ...

It's this sliding, in dynamic loading, that concerns me re frictional heat.

> [it] continues to tighten as a [noose] which eventually failed at 9.4kN which seems quite an reasonable value for a somewhat older rope of this diameter. I tested a standard bowline with stopper to give a baseline and this failed at 7.9kN

(Why the stopper?)
These values are intriguing. Assuming the bowline's strength to be
about 65% of tensile, your one check would put the rope strength
at about 12.1 kn, and the noose at 77% .

> At no stage does there seem any potential for the mess to change into an 8 and this in fact seems impossible without loosening and manipulating the knot.

It depends on how the YoBowl is transformed by the setting
on its tail : it is possible to disorient it so that the tail is NOT within
the rabbit hole --it is pulled across/under the mainline--,
and THEN there is a topological (if not geometrical) "8" in the end,
which itself might take some further mangling to get into recognizable
form (vs. a sort of *two-circles* orientation).

> Ring pulled there seems no difference between the two ways (the correctly dressed Yosemite and the loop pulled up through variant) as they broke at 19.8kN and 20.1kN respectively.

Wow, THIS is a surprisingly high value --let's average it as 20kN.
Assume 12 kN for the rope (per above deduction)
and that the closed ring so loaded takes a severe bias in sides' tension
--i.e., that knot compression adds length (lessens tension) on its side
(which doesn't flow around the frictive end points of the tape sling
(and what's opposite this : a test device smooth metal pin?!))--,
and take the unknotted side to near 100% (or nearly 12kN);
that leaves 8kN for the knot,
putting the sheet-bend-like (rather : Lapp-knot(reverse sheet bend)-like)
knots at equal strength to the bowline. !!?
Hmmmm, that's a surprise.

> If [the] Yosemite bowline ... spare end falls out of the last tuck you revert naturally enough to a normal bowline.

Again, this depends upon how disoriented the YoBowl becomes
upon that tail-pull setting --it's possible to end up otherwise
(as in the _On Rope (1st ed)_ Knots chapter cover page image.


*kN*
sikcby - on 22 Jul 2012
In reply to stefanfischer:

Interesting, but without pull tests this can be only an illusion.

Don't tell Craig Conally... He loves the YoBow. :)

And if you want to get scared take a look of what a figure eight can done when no properly dressed or when is side charged.
Ash_Johnson - on 24 Jul 2012
In reply to stefanfischer:

Why anyone would actually use a bow is beyond me. It reduces the strength of the rope and can easily be tied incorrectly.
GrahamD - on 24 Jul 2012
In reply to Ash_Johnson:

I use a bow to tie my laces. I'm sure most people do.
highclimber - on 24 Jul 2012
In reply to Ash_Johnson:
> (In reply to stefanfischer)
>
> Why anyone would actually use a bow is beyond me. It reduces the strength of the rope and can easily be tied incorrectly.

do you actually know what you're talking about? All knots reduce the strength of ropes, but no knot reduces the strength to a point where is becomes a risk.
I imagine you've never fallen onto a fig8 repeatedly and then tried to undo it? when you do, make sure you've got either a knife or a bit of time spare!.
Justin T - on 24 Jul 2012
In reply to highclimber:

This thread is still going? Really?!

To the people who think the YB is dangerous: Don't use it
To the people who think the YB is not dangerous: Carry on

Problem solved!
GrahamD - on 24 Jul 2012
In reply to quadmyre:

What about people who think the YB is not dangerous but nevertheless don't use it because its uneccessarily complicated ?
beardy mike - on 24 Jul 2012
In reply to GrahamD: What about people who think a figure of eight is easy to mistie (having watched loads of noobs get it wrong repeatedly)...

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