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How strong is your knot?

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Re: How strong is your knot?

#111

Post by Balgair »

dekhn wrote: post #105

i've always thought it woudl be interesting to do large-scale simulations of knots using a physics engine- generate random topologies, pull both ends, compute some physical parameters such as "force required to pull apart". Then sort of walk around knotspace using genetic algorithms to evolve new knots. THere is probably a much more practical RL approach that doesn't require GA>

Knots aren't super difficult to 'program' in the first place. The first computers were for looms and their weft patterns, after all. It's always been strange to me that no one has decided to set up the math of knots. Most knots are just subtle changes to the same basic elements (bite, over/under, loops, etc). I'd figured there are enough Eagle scouts with PhDs in math to have done this already, but no.

Re: How strong is your knot?

#112

Post by Balgair »

throw7 wrote: post #8

The zeppelin has always been my favorite "knot" (the zeppelin is a bend), but one knot is not the "best"... the alpine butterfly they compare it with is a loop. They're used in different contexts. I'm just knot layman, but other knots I like are: the icicle hitch, bowline (+yosemite stopper), trucker's hitch, siberian/evenk/halter hitch, tumble hitch, and the chinese button knot.

THANK YOU! The Zeppelin bend is my favorite knot, simply due to the name.

A useful, if relatively unknown knot, is Ashely's Stopper Knot, great for the little strings that go into hoodies.

https://en.wikipedia.org/wiki/Ashley%27s_stopper_knot

Re: How strong is your knot?

#113

Post by wrycoder »

IgorPartola wrote: post #89
wrycoder wrote: post #40

Earlier quoted context omitted.

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.

It's an interesting and decorative knot - I've not seen anything like it before. I'll have to give it a try. I'm trying to think of another quality bight knot that can be tied with the object in place. Not the bowline, not the butterfly.

Re: How strong is your knot?

#115

Post by thfuran »

Balgair wrote: post #111
dekhn wrote: post #105

i've always thought it woudl be interesting to do large-scale simulations of knots using a physics engine- generate random topologies, pull both ends, compute some physical parameters such as "force required to pull apart". Then sort of walk around knotspace using genetic algorithms to evolve new knots. THere is probably a much more practical RL approach that doesn't require GA>

Knots aren't super difficult to 'program' in the first place. The first computers were for looms and their weft patterns, after all. It's always been strange to me that no one has decided to set up the math of knots. Most knots are just subtle changes to the same basic elements (bite, over/under, loops, etc). I'd figured there are enough Eagle scouts with PhDs in math to have done this already, but no.

What do you mean? Knot theory is a field.

Re: How strong is your knot?

#116

Post by wenc »

Balgair wrote: post #111
dekhn wrote: post #105

i've always thought it woudl be interesting to do large-scale simulations of knots using a physics engine- generate random topologies, pull both ends, compute some physical parameters such as "force required to pull apart". Then sort of walk around knotspace using genetic algorithms to evolve new knots. THere is probably a much more practical RL approach that doesn't require GA>

Knots aren't super difficult to 'program' in the first place. The first computers were for looms and their weft patterns, after all. It's always been strange to me that no one has decided to set up the math of knots. Most knots are just subtle changes to the same basic elements (bite, over/under, loops, etc). I'd figured there are enough Eagle scouts with PhDs in math to have done this already, but no.

Knot theory

https://en.wikipedia.org/wiki/Knot_theory

Re: How strong is your knot?

#117

Post by 0xffff2 »

jolmg wrote: post #61
dragontamer wrote: post #16

My list of favorite knots: 1. Square Knot / Reef Knot -- This is the shoelace tie, and its one of the simplest knots. Learn this knot backwards and forwards you'll use it a lot. Avoid the granny knot (a mistaken reef knot). Beginners will often tie the granny knot instead of the square knot. If you can do a square knot, the "Surgeon Knot" is a useful variant which is more secure. 2. Figure Eight -- Superior to the ov…

Regarding cable lacing, it seems more complicated to add or remove cables at different points of the lace, at least when compared to velcro cable ties. However, it is cheaper and does save you time for when you don't have cable ties but do have some versatile string laying around.

I think about the only place that cable lacing is still actually used is in space craft wiring harnesses, where the harness is generally not modified once built. Even then, NASA at least doesn't use the single continuous strand method of lacing. We tie "spot ties" which function identically to Velcro with the exception that you have to cut them if you do modify the harness.

Re: How strong is your knot?

#118

Post by e12e »

japhyr wrote: post #20

My favorite, as many others are sharing here, is the figure 8. For climbing, it's a super versatile knot and there's lots of variations for specific use cases. It's also a great knot for discussing the properties of a good knot. I also have found the trucker's hitch really useful from time to time. It allows you to tie down a load, for example a kayak on top of a car. You tie the initial hitch, and then you get to cr…

Doesn't he tie the loop the wrong way in both cases? The (regular) shoe lace knot should be like the reefer knot, not the granny knot.

I've had less problems with simple shoe lace knot after I made sure the loops are correct.

Re: How strong is your knot?

#119

Post by dekhn »

thfuran wrote: post #115
Balgair wrote: post #111

Earlier quoted context omitted.

Knots aren't super difficult to 'program' in the first place. The first computers were for looms and their weft patterns, after all. It's always been strange to me that no one has decided to set up the math of knots. Most knots are just subtle changes to the same basic elements (bite, over/under, loops, etc). I'd figured there are enough Eagle scouts with PhDs in math to have done this already, but no.

What do you mean? Knot theory is a field.

knot theory is abstract- I care more about the material sciences aspect.

Re: How strong is your knot?

#120

Post by dragontamer »

dilyevsky wrote: post #59
dragontamer wrote: post #16

My list of favorite knots: 1. Square Knot / Reef Knot -- This is the shoelace tie, and its one of the simplest knots. Learn this knot backwards and forwards you'll use it a lot. Avoid the granny knot (a mistaken reef knot). Beginners will often tie the granny knot instead of the square knot. If you can do a square knot, the "Surgeon Knot" is a useful variant which is more secure. 2. Figure Eight -- Superior to the ov…

2. False. (Double) overhand aka euro death knot is superior for joining two ends of rappel line due to its smaller profile - lower probably of getting jammed on pull

The "overhand knot" is the basis of many other knots. For example, the half-hitch and double-overhand knot.

While double-overhand and half-hitches are very useful, the "vanilla" overhand knot is among the weakest of knots and should be avoided in almost all circumstances. I can't say that I've ever found a good use of the "vanilla" overhand knot.

I'm not a climber. I just happen to have some twine on my often for daily use.

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