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How strong is your knot?

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Re: How strong is your knot?

#81

Post by brndr »

JshWright wrote: post #33
slowhand09 wrote: post #24

Earlier quoted context omitted.

Been using bowlines for safety(fire dept) and sailing 35yrs. Never ever ever seen a proper bowline "shake loose". Can tie it weakside one-handed, upside down, behind my back, in the dark, underwater, while brushing my teeth.

You use a bowline for life-safety in rescue operations? That's really unusual, in my experience (firefighter/rescue tech in upstate New York)

I volunteer for a lifesaving organization in Germany and the bowline is one of the most important knots there. One example is diving, where the diver is secured by a bowline around his hip.

Re: How strong is your knot?

#82

Post by oasisbob »

knot_knots wrote: post #73
kajecounterhack wrote: post #52

For standard knots the Klutz book of knots is really excellent! https://www.amazon.com/Klutz-Book-Knots-John-Cassidy/dp/0932... The article doesn't mention fishing knots; in case anyone's curious anglers care a lot about knot strength but strength changes based on whether you lubricated the knot when tying and what kind of line you used to tie it (braid vs smooth fluorocarbon for example). My favorite fishing knot is…

Joining two lines, (of the same or different diameters) is very much of interest in climbing, and these knots often do "collapse." The simplest/most common knot used for this purpose is even named for fishing- the double fisherman's knot. It is used for joining the ends of a cordelette, combining ropes for rappelling or ascending, or in a single ended version, backing up (collapsing on) a knot used to tie in to the r…

In climbing, the offset overhand bend (EDK) is also very commonly used. It's arguably simpler than the double fishermans.

I'm a huge fan of the zeppelin bend - it's a bit exotic, but is catching on in some climbing circles. Competitive tree climbing is carefully adjudicated for safety... in the PNW at least, judges have absolutely no problem with it being used as a joining knot on a lifeline.

Re: How strong is your knot?

#83

Post by woofie11 »

Intermernet wrote: post #74
alister wrote: post #65

I have a knot problem that I think pretty much everyone has encountered. How do you tie a bundle of branches or a cardboard box or something compressible as tightly as possible? The first way everyone tries is to cross the rope like you would for shoelaces, then putting pressure on the crossed rope with your finger, and trying to cross the ends of the rope with your one free hand to finish the knot. Inevitably the kn…

If you tie an alpine butterfly somewhere in the rope, and then pass the other end through it, you can achieve a 2:1 pulley system in the rope. This greatly increases the compression of the lashing. Hard to explain, but you're basically using a fixed loop in the line as a pulley to increase the force applied.

You can do the same thing going around twice. It's simpler, and gives the same mechanical advantage.

Re: How strong is your knot?

#84

Post by woofie11 »

alister wrote: post #65

I have a knot problem that I think pretty much everyone has encountered. How do you tie a bundle of branches or a cardboard box or something compressible as tightly as possible? The first way everyone tries is to cross the rope like you would for shoelaces, then putting pressure on the crossed rope with your finger, and trying to cross the ends of the rope with your one free hand to finish the knot. Inevitably the kn…

The standard ratcheting knot is the rolling hitch, although several people on this thread mentioned potentially better knots for this application. My general trick is to use rolling hitches together with the bow-and-arrow technique. The concept behind bow-and-arrow is simple -- if you pull on a segment of rope perpendicular to the rope, it gets tighter.

If I'm tying something to my roof rack, I'll get is as tight as I can going around a few times with a rolling hitch. Then I'll get a piece of rope to pull on that one. How you do that depends on domain.

Re: How strong is your knot?

#85

Post by dsego »

strstr wrote: post #17
WilTimSon wrote: post #11

I'm somewhat fascinated by people's ability to tie knots that are more complicated than the basic shoelace one. I've watched hundreds of videos on knot-tying and, even with basic step-by-step instructions, can't manage one properly. Is it just the fact that this stuff is better taught practically or am I just somehow the worst knot-tier of all? Even that reef knot gif eludes me...

I couldn’t remember them until I started needing them. Figure eight, clovehitch, barrel knot, overhand, and fisherman’s are my daily drivers for climbing. Prussiks are useful, but there are more efficient ways of doing progress capture. Bowlines can be used instead of figure eights, but they can shake open if you aren’t careful, which is obviously bad.

You can add a stopper knot to the bowline I think.

Re: How strong is your knot?

#86

Post by Intermernet »

woofie11 wrote: post #83
Intermernet wrote: post #74

Earlier quoted context omitted.

If you tie an alpine butterfly somewhere in the rope, and then pass the other end through it, you can achieve a 2:1 pulley system in the rope. This greatly increases the compression of the lashing. Hard to explain, but you're basically using a fixed loop in the line as a pulley to increase the force applied.

You can do the same thing going around twice. It's simpler, and gives the same mechanical advantage.

Much more friction and stretch in the system. The less rope, the less stretch.

Re: How strong is your knot?

#89

Post by IgorPartola »

wrycoder wrote: post #40
IgorPartola wrote: post #21

If you want a fun one, look up Somerville Bowline. Great take on a bowline that is non-directional, non-collapsing, very hard to get wrong, small, quick to tie, and cannot be undone under tension. Oh and it’s completely symmetrical so you can pull on either end.

Fun, heh. It does look like it would have a tendency to jam and be hard to untie. One of the key points of a good knot is that it be easily untied once the strain has been removed.

Depends on the load of course, but in my experience having tied it a lot, it only jammed up once, taking an extra thirty seconds to undo. This was when I put about 200 lb on it and swung around a bunch. Jute rope also has a ton of friction, synthetic being smoother would be even less likely to jam.

Re: How strong is your knot?

#90

Post by 11235813213455 »

alister wrote: post #65

I have a knot problem that I think pretty much everyone has encountered. How do you tie a bundle of branches or a cardboard box or something compressible as tightly as possible? The first way everyone tries is to cross the rope like you would for shoelaces, then putting pressure on the crossed rope with your finger, and trying to cross the ends of the rope with your one free hand to finish the knot. Inevitably the kn…

maybe Cabestan (reinforced with a few more loops) or hangman's knot
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