Tying Bolt Snaps

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Dan Gibson

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A loose knot will allow the line to be cut by sharp edges much more easily. A good example is the bolt snap on the goodman handle. Unless one wants to potentially replace a bulb or test tube, the best way to prevent this is to make the bolt snap stand proud. The best way to do that is a tight knot which the square knot will do.

do it easy:
It isn't as tight as a square knot would be, so there is more "play" in the loop. I trade a tight "knot" for a secure one.
 
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c555

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Mo2vation:
I've never had a zip tie come undone.

That said (roll tape, boys...) I've just recently converted all my stuff to Cave line.

All of it.

Back up lights, SPG, Regs, etc. All cave line now.

Who knew.

Can Diet Coke be far behind....

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Ken

I had also been thinking of using zip ties, is there any reason not to? It seems they are easier to use and less likely to fail. Any thoughts? If there is a reason not too I will just stick with the knot that was posted. Thanks for the help everybody!
 

Mo2vation

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c555:
I had also been thinking of using zip ties, is there any reason not to? It seems they are easier to use and less likely to fail. Any thoughts? If there is a reason not too I will just stick with the knot that was posted. Thanks for the help everybody!

I used zip ties everywhere for years. I didn't, and I don't see a problem with it. They last and last, are quick and easy to replace and just make sense.

I was pretty firm about it. I mean, why go through all of the hoopla of the cave line and all that, right?

I finally "caved"... I don't know what triggered it, really. Maybe my move towards tech diving. I dunno.

It was something I did just recently. I still keep some zip ties in my wetnotes for in-water repair. But none of the cave line ties have failed yet.

Its like when you decise to go from a Bic to a Fountain Pen. I made the move because of the tradition, the intimacy and the quality. There is more flexibility to the cave line, too. I dunno. Still working on what made me change.

---
Ken
 

ItsBruce

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1. The knot known as a square knot is also known as a reef knot as it was used to tie a loop in a line that was being used to put a reef into a sail. The thing that made the knot suitable for this task was that it was easy to untie. Unless one really melts the end into a huge blob, it can still come lose. And, melting the end into the body of the know significantly reduces the strength of the line.

2. I don't trust zip ties when they are in tight loops or under great loads. And, there is always the sharp edge where the tail is cut short.
 

riguerin

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One advantage of the cave knot versus zip ties is that final perpendicular loop helps isolate the bolt snap from the mounting piece. Depending on what the snap is being mounted to it can help prevent/minimize metal-to-metal contact.

Image-7B378B5C2F7D11DA.jpg
 

OE2X

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This might help out:

I too have found that a regular square knot is a bit slippery with cave line. What I do is to tie a square knot with one extra step.

The first time you cross your lines or the first step that you do when tieing a regular square knot should be repeated one more time.

What this does is give an extra bite to the line. Pull as tight as you can.

Then finish the square knot and melt the ends back onto the knot itself.

In three years I have yet to have a knot fail.
 

Mo2vation

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ItsBruce:
2. I don't trust zip ties when they are in tight loops or under great loads. And, there is always the sharp edge where the tail is cut short.

Nail clippers. Curved cutting blade.

No sharp ends.

---
Ken
 

cmalinowski

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OE2X:
This might help out:

I too have found that a regular square knot is a bit slippery with cave line. What I do is to tie a square knot with one extra step.

The first time you cross your lines or the first step that you do when tieing a regular square knot should be repeated one more time.

What this does is give an extra bite to the line. Pull as tight as you can.

Then finish the square knot and melt the ends back onto the knot itself.

In three years I have yet to have a knot fail.
same here.
Chris
 
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I have learned my lessons quickly and have had both a square knot which I melted and zip ties both fail within my first 50 dives.

The square knot is a great knot when it is under load. However the properties that make this knot easy to untie also make it easy to come undone unexpectidly. I lost my UK C8 one a shallow night dive due to a square knot. Luckly I came back the next day and was able to find it.

Zip ties are very stong and hold up well to forces acting along the length of the tie. However they are prone to fail when horizontal or twisting forces are applied. I almost lost a dive knife to zip ties but luckily it fell off during a boat dive just before I entered the water.
 
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redacted

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Mo2vation:
I've never had a zip tie come undone.

I have had zip ties fail. They were small cheap ones but that just changes the probability, not the possibility. Regarless of whether I use zip ties, cave line, or whatever; if it is the only connection (like on lights) I double them up. If there is already a backup connection (like an SPG) then a single tie is OK.
 
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