water knot in rope

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water knot in rope

Postby GroundquestMSA » Mar 18, 2015 2:31 pm

Is the water knot disfavored for use in rope? Does it require more or less tail or backup than an edk?
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Re: water knot in rope

Postby caver.adam » Mar 18, 2015 3:19 pm

The Water Knot has a tendency to work itself undone, particularly in rope. This happens at relatively low forces and is especially bad in situations where loads are applied and then released over and over. In webbing this knot is less likely to undo itself but you should leave sufficiently long tails to account for this.

Is there a particular reason you are looking to use this knot instead of another bend knot? Depending on whether you ever need to untie the knot, there are several bend knots to choose from.
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Re: water knot in rope

Postby GroundquestMSA » Mar 18, 2015 3:31 pm

caver.adam wrote:Is there a particular reason you are looking to use this knot instead of another bend knot?


Just curious. I've been experimenting with different knots to join ropes, and compactness is hard to get with pit rope. I like the Idea of joining with the most compact knot possible and then isolating the knot with an alpine butterfly, a method which was mentioned elsewhere on the forum.
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Re: water knot in rope

Postby Rangeoflight » Mar 18, 2015 11:20 pm

You could use a barrel knot/double fisherman's. Relatively compact. Testing presented at the last ITRS showed 80% strength efficiency in 1/2" rope. No need to isolate it with a butterfly either since the butterfly is a weaker knot (~65% in the same rope).
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Re: water knot in rope

Postby GroundquestMSA » Mar 18, 2015 11:56 pm

The butterfly was intended to take the load so that it would be easy to untie, and to provide a clip-in loop.
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Re: water knot in rope

Postby caver.adam » Mar 19, 2015 8:53 am

I love the double fisherman's, but it's darn near impossible to untie once loaded.
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Re: water knot in rope

Postby LukeM » Mar 19, 2015 9:47 am

You may be aware of this already, but you can tie a figure-8 bend that includes a loop for clipping in. It's not the most compact knot, but it accomplishes two goals in one and is easy to tie and remember. Start one rope with a figure-8 on a bight and use the other rope to trace it like you would in a normal figure-8 bend.
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