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Figure 8 vs Bowline
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By Chris90
From Unity, Maine
Oct 2, 2010

Some people tie in with the figure 8, some tie in with the bowline. But I have heard that the bowline weakens the rope. Does it really weaken it more than the figure 8? are there any other advantages/disadvantages?


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By MattPeterson
From Provo, UT
Oct 2, 2010

I believe a figure eight retains about 80% of the strength of the rope while a bowline is about 65%. Those are approximate theoretical values though - a lot of factors can affect the strength of a knot.


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By matt davies
Oct 2, 2010

One problem with the bowline for climbing is it can come undone if not weighted. It is designed to be easily untied after being loaded.
Two ways around this are the double bowline:notableknotindex.webs.com/doublebowline.html,

and the bowline with a yosemite tie-off:www.sherrilltree.com/Learning-Center/Knots

I like to tie in with the double bowline if I'm doing sport routes where I'm going to whip repeatedly, its just a little easier to untie, but for every other climbing application I use the figure eight. While the bowline may weaken the the rope a little more than a figure eight, its not going to effect normal climbing situations, in my opinion. Climbing ropes are wicked strong.


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By P LaDouche
From CO
Oct 2, 2010

I prefer the square knot myself.


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By Robert Cort
Oct 2, 2010

The other advantage to the figure 8 is that it's easy for your partner to look at it and verify you have a good tie-in knot. Not as easy with the double bowline.


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By rgold
From Poughkeepsie, NY
Oct 2, 2010
The traverse out to the Yellow Ridge on the Dogstick Ridge link-up.  Photo by Myriam Bouchard

Every knot "weakens" the rope.

In most tests, the bowline more so than the figure 8.

Figures obtained from testing vary considerably. I don't believe there are any reliable figures.

But the rope never (as in NEVER) breaks at the knot, so the relative strength is completely immaterial for climbing purposes.

We should stop speaking of the bowline, which no one (as in NO ONE) uses unadorned for climbing (at least not nowadays), and adopt some terminology like "climber's bowline" for the bowline with the so-called Yosemite finish (in use for many years and in many locales before it showed up in Yosemite) and finishing stopper knot. This knot is not unstable, can be ring-loaded, and doesn't loosen, and is far easier to untie after severe and/or repeated loading than a figure 8.

The most interesting and least-examined aspect of tie-in knots is the fact that through tightening, they absorb some fall energy. I've never seen the figure 8 compared to the bowline in this category.

Personally, I use a (climber's) double bowline for lead climbing, not because it is marginally stronger, but because I suspect the extra turn might provide more energy absorbtion. For top-roping in the gym, a single (climber's) bowline is fine.

As for verifiability, I must say I've never understood the idea that someone else should have to check something as fundamental as your tie-in knot. (I do understand why guides would want to do this, because they have to assume, rightly or wrongly, that their clients are incompetent.)

If you can't get your tie-in right, wow, you just plain shouldn't be climbing IMHO. (That said, it isn't a bad idea to note whether or not your partner has tied in at all...)

That said, I don't know of any "incorrect" way to tie a bowline that doesn't instantly fall apart in your hands before you get to the "Yosemite finish" stage. (There are two variations, sometimes called left and right, or regular and Dutch Navy, but there is no evidence that one is really preferable to the other so no clear penalty for tying one when you intend the other.)


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By Eric Krantz
From Black Hills
Oct 3, 2010
smoke break, pitch 5 or 6 (or 7??) of Dark Shadows

rgold wrote:
But the rope never (as in NEVER) breaks at the knot, so the relative strength is completely immaterial for climbing purposes.


Huh? In pull tests, the rope always breaks at the knot. If you have an f-ed up rope with damage to the core, it might break there. But otherwise, it's gonna break at the knot. It doesn't really matter anyway, no one's rope breaks while climbing. Someone else said it, ropes are "wicked strong".

rgold wrote:
We should stop speaking of the bowline, which no one (as in NO ONE) uses unadorned for climbing (at least not nowadays)


Sometimes I do. The bowline is solid.

rgold wrote:
As for verifiability, I must say I've never understood the idea that someone else should have to check something as fundamental as your tie-in knot.


Would have prevented Lynn's fall. Lucky she didn't get hurt worse (or die). There's probably many more stories like that. I've only been climbing 10 years and my partner 18, but still make it a point to check her belay, knot, and rappel every time.

Wait, maybe I'm being presumptuous, or falling for a troll. Was yours a serious post? I'm kinda dense sometimes and don't always get sarcasm.


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By jack roberts
Oct 3, 2010

I have several partners who have been climbing for a long time (25-30 years) and they ALWAYS tie in with a bowline.

And yes, in pull tests the rope ALWAYS breaks at the knot.


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By thedogfather
From Las Vegas, NV
Oct 3, 2010

traceback bowline for sport.

Good picture down a bit on this link:
students.washington.edu/climb/forum/viewtopic.php?f=19&p=325>>>

Super easy to untie and it is a redundant bowline.


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By bearbreeder
Oct 3, 2010

rgold wrote:
As for verifiability, I must say I've never understood the idea that someone else should have to check something as fundamental as your tie-in knot. (I do understand why guides would want to do this, because they have to assume, rightly or wrongly, that their clients are incompetent.) If you can't get your tie-in right, wow, you just plain shouldn't be climbing IMHO.


lynn hill screwed up her tie in back in the early 90s and fell from the top of a pitch in france ... she was saved by a tree

basically the greatest female climber ever almost died because she forgot her knot and her partner didnt check it

i ALWAYS check my partners knot ... in fact if they are a hawt gurl i make sure to physically check it ;)

lol


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By sgiguere
Dec 8, 2012

The truth is that a figure eight is more safe than the double bowline, but both are perfectly safe for climbing. Here is an article which provides links to actual data: sgiguere.hubpages.com/hub/Rock-Climbing-Knots-the-Double-Bow>>>

Safe climbing!


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By Ray Pinpillage
From West Egg
Dec 8, 2012
Cleo's Needle

I'm not going to click that link, spammer.


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By 20 kN
From Hawaii
Dec 8, 2012

Chris90 wrote:
Some people tie in with the figure 8, some tie in with the bowline. But I have heard that the bowline weakens the rope. Does it really weaken it more than the figure 8?

What is really important about this question is the fact that the question itself is unimportant. You will never approach the breaking strength of a dynamic rope in a rock climbing scenario, regardless of what knot you use. So tie in with whatever you want, but dont base your decision on strength retention as it does not matter. However, in other fields such as load hauling, SAR, highlining, and the like, knot strength retention is important. But in climbing, not so much.


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By sgiguere
Dec 9, 2012

Ray Pinpillage wrote:
I'm not going to click that link, spammer.


You don't have to... I wrote the article because I was disappointed with the typical forum posts on this subject, such as "I tie in with the double bowline all the time, and I'm not dead yet." All that I found were unsubstantiated opinions on the matter, and I wanted real answers. I finally found some actual research, and I wrote an article about it.

If anyone does check it out, let me know what you think. I'd love to hear any suggestions you have.


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By sgiguere
Dec 9, 2012

Here. I literally answer this question directly, so if you don't want to click the link, you don't have to. If you are interested in the research I have to back this up, you can find it cited in my article:

"Every knot, no matter how perfect, weakens the rope. Some knots are considered stronger than others in that they do not cause as much uneven stress on the core of the rope. A rope almost never breaks within the knot itself, but at a point just outside of the knot where the weight load of the knot is actually distributed.

The figure eight is a stronger knot than the double bowline, but the double bowline is still more than strong enough to protect a climber on reasonably safe equipment. We need to take into consideration other factors besides knot strength in order to make a choice between the two."

20 kN is correct, the knot strength isn't a valid consideration in this case, because both are strong enough to do the job.


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By michaeltarne
Dec 9, 2012

I'm curious as to why you bumped this >2 year old thread when there have been much more recent discussions.


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By MJMobes
From The land of steady habits
Dec 9, 2012
modern man

is hubpages a spammer site or similar to ehow or ask.com? do you get paid for hits? the info is not too bad in fact its decent, just wondering.


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