To knot or not to knot

[kelemvor]

Okay so here's the thing. I can't tie knots to save my life. I wasn't a boy scout, and if I had been they probably would have kicked me out when it came time to tie knots. I can tie a square knot and that's about it. It sucks for pretty much all things scuba as far as I can tell.

I've got some bungee adapters for my wrist mount dive computers and need to tie knots in the bungee to stop it from pulling out. Ideally I'd like it to be a knot that can slide/adjsust without retying. I know such a thing exists, as a friend made me some nice reg necklaces with such a knot.

What are the names of the type of knot I should be using? I'll take it from there and google videos or instructions on how to do it, and hopefully figure it out.

I'm the kind of guy who likes to fully understand something before doing it. However when it comes to knots, I just can't seem to wrap my brain around them. I've had a few folks show me how to tie some knot or another and I have never been able to duplicate them. At the moment, I'm quite motivated to learn and hopefully that will make the necessary difference.

 

[Storker]

For the necklace: Prussik loop.

Bungee cord slides pretty easily, so knots based on the fisherman's knot or the double fisherman's knot generally are the best ones. They can slide, too, depending on how tight you pull the knot.

 

[Akimbo]

I understand your problem and have seen it many times. Difficulty understanding and remembering knots isn't "stupid" or inexperience... people's brains are just wired differently. I encourage you to try and understand knots. However, it gets complicated because some materials just don't hold proper knots as well as others. A neat trick that helps overcome problems with slippery materials is to use an adhesive. It is NOT as solution to prevent improper knots from coming loose, but can be really handy with slippery small line (string).

More permanent adhesives like cyanoacrylates (Super Glue) can be used when untying the knot isn't a concern or more resilient options like Silicon or wetsuit cement when it is.

Okay so here's the thing. I can't tie knots to save my life. ...

BTW, you really want to avoid commercial diving. VERY often, your life (or worse, someone else's) does depend on the knot you tie.

Edit: correct typo

 

[tbone1004]

double fishermans knot

 

[Storker]

it gets complicated because some materials just don't hold proper knots as well as others. A neat trick that helps overcome problems with slippery materials is to use an adhesive.

I've found that some qualities of bungee are really bad at holding the knot. Even a properly tied double fisherman can slide. If that's the problem, I like to tie a simple overhand knot at the end of the line so it won't slip through the double fisherman.

For good rope which holds the knot well, 99% of my knot tying needs are covered by a small handful of knots: Half hitch/clove hitch, bowline, sheet bend, overhand and perhaps the square knot. They also form the basis for most of the other knots I use. The half hitch is the basis for quite a few other knots like the round turn with two half hitches or the rolling hitch, and the overhand - easily modified into the double overhand - is the basis for all the different fisherman's knots and loops.

 

[Storker]

double fishermans knot

...is what it's called if it's pulled tight to form a bend. If you leave the loop open, it's called a Prussik loop

 

[tbone1004]

...is what it's called if it's pulled tight to form a bend. If you leave the loop open, it's called a Prussik loop

touche

 

[Akimbo]

...
For good rope which holds the knot well, 99% of my knot tying needs are covered by a small handful of knots: Half hitch/clove hitch, bowline, sheet bend, overhand and perhaps the square knot. ...

Agreed, but some materials will work loose over time no matter how good your knot skills are -- especially with frequent submersion cycles. Another trick that works well in larger 3-strand twisted line is to tie the knot with a longish bitter end. Untwist the strands and weave the bitter end in similar to a splice. Tension on the line will add a lot of friction. It is quick and can be done with gloves. That trick is a near-necessity for 3-strand Polypro.

Warning to All: All knots reduce the rated tensile strength of line, often between 50 and 75%!

 

[Storker]

Another trick that works well in larger 3-strand twisted line is to tie the knot with a longish bitter end. Untwist the strands and weave the bitter end in similar to a splice.

You mean basically splicing the strands of the fall into the standing part? Why not just do a proper splice, then?

(On an unrelated note, I learned something just now: I didn't know that the fall is also called the bitter end. Now I know. Cool.)

 

[kelemvor]

Warning to All: All knots reduce the rated tensile strength of line, often between 50 and 75%!

I've no doubt that you are correct. However, I just need the line to hold a regulator to my neck or a dive computer to my wrist. I'm not particularly concerned with the bungee breaking due to load. Should I be?