Bungee mount for Petrel

[tursiops]

how to link two ends of the bungee without a knot?

Use 2 hog rings (and appropriate pliers) and a short length of shrink wrap over the joint. Be sure and put the shrink wrap segment over the bungee before tightening the hog rings. Don't ask how I know.

 

[buddhasummer]

Use 2 hog rings (and appropriate pliers) and a short length of shrink wrap over the joint. Be sure and put the shrink wrap segment over the bungee before tightening the hog rings. Don't ask how I know.

What are "hog rings" ? Cheers.

 

[lowviz]

Yet another option:

Use urethane round drive belting. (McMaster-Carr) Tough stuff. Comes in colors.
Not as stretchy as bungee but works well. Just melt the ends on a hot Teflon coated surface and stick together. Cut off the flashing.

Below is one of my neck rings. Doesn't scratch the tank neck and can be removed without removing the valve. Start with a much smaller size for your DC.

Doubtful? Try it for yourself, make a loop, step on it and try to break it by pulling upwards.



I like the straps and the grommets, but I would use two loops, if one breaks you still have your DC.

 

[tursiops]

What are "hog rings" ? Cheers.

The rings need to be stainless, and you can get them from places like West Marine.
WEST MARINE Hogrings for Shock Cord | West Marine
But the pliers can be cheap, for example these from Harbor Freight.
Straight Hog Ring Pliers

 

[DA Aquamaster]

Thanks to Stuart, I ended up with this.

View attachment 220735View attachment 220736View attachment 220737

Works fine. Tried in pool but anyone have any idea how to link two ends of the bungee without a knot? I'm using a zip tie on each end of a reef knot. Works great, looks kludgy.

Hog rings are a good idea as you get a smaller, cleaner more secure connection that won't unknot itself.

An alternative is to form the bungee loop, the stretch both pieces as far as you can where they meet and while holding that tension to thin the bungee as much as possible (you'll need a vice or a helper) tightly lash the two together with a dozen wraps of heavy nylon or dacron upholstery thread. When you release tension the bungee expands and is held even tighter. Then slide the heat shrink tubing over the joint. The advantage over a hog ring is that the thread lashing won't cut the cover or the elastic core over time.


I'm also a big believer in redundancy. I would add an overhand knot on the other side between the two straps so that in the event the bungee breaks during a dive, the knot (and the hog ring or lashed connection on the other side) will prevent the bungee from unthreading through both straps, and at least one side of the bungee will still keep the Petrel on your arm.

 

[stuartv]

Thanks to Stuart, I ended up with this.

View attachment 220735View attachment 220736View attachment 220737

Works fine. Tried in pool but anyone have any idea how to link two ends of the bungee without a knot? I'm using a zip tie on each end of a reef knot. Works great, looks kludgy.

That looks cool, but I do have some thoughts.

- As others have mentioned, I would do something so that if one side lets go, the computer can't just fall off your arm. That is why I went with two completely separate bungees. Two bungees is one and one is none, right? LOL

- Shorter webbing and longer bungees will result in more stretch being available. Having the bungee part 1/2" longer and the webbing 1/2" shorter should let you stretch the bungee part to about 1" total longer overall length, I think. That might make it easier to get on/off in some situations.

- The way you've done it does not allow for any adjustability of the length of the bungees, that I can see. And you may not need it. I did mine like I did because the part where the bungee is doubled back and tied lets me easily slide that knot back and forth to make the overall bungee loop around my arm longer or shorter. I think I will need this since I will dive with my Petrel while wearing a 3/2 wetsuit sometimes and a dry suit with undergarments other times.

- I prefer having the bungees held on with knots instead of zip ties, hog rings, or anything else because I can fix it, re-do it, or whatever at any time with no tools or parts needed. If a bungee lets go and is lost or just needs to be replaced for any reason, all I need is another piece of bungee. Basically, it's about as simple as it can get, adjustable for fit, and redundant.

I finally got to use my new setup yesterday in a pool. It was a little tough to slide it onto the arm of my dry suit as I had to get it over the Kubi rings for my dry gloves. But, in hindsight, I had the bungees adjusted to a shorter length that would have worked with a thin wetsuit. I should have slid the knots down a bit to make the loops bigger. Still, it did work as it was. And once it was on my arm it was GREAT! My computer didn't move around at all and I had no strap tails flapping around.

 

[tridacna]

I'll try independent straps-gonna rethink the knots. Not possible to move the grommets, that would require hammering too close to the body. I must say that it fits quite well now on a 3mm suit which is what I dive in the winter (warm water in pool or Carib) but see the point when I switch over to the drysuit. This is a lotta work but I dislike the clips supplied by SW. I need to be able to don without help and was unable to do that with those.

 

[rhwestfall]

I'll try independent straps-gonna rethink the knots. Not possible to move the grommets, that would require hammering too close to the body. I must say that it fits quite well now on a 3mm suit which is what I dive in the winter (warm water in pool or Carib) but see the point when I switch over to the drysuit. This is a lotta work but I dislike the clips supplied by SW. I need to be able to don without help and was unable to do that with those.

I've seen folks with bungied comps first put it on the sleeve, then put their arm in the suit when dressing.... I too am struggling with wet/dry/bare exposure and fit....

 

[stuartv]

If it's just donning that's a problem, have y'all tried fastening the clips with the straps really loose, slipping it onto your arm, then tightening the straps?

With the stock straps, I was donning with the straps loose, holding the Petrel against my body (sandwiched between arm and body) to keep it still, then pulling the straps to tighten. Then I would reposition the Petrel to where I wanted it. That worked okay for me. My reason for doing this bungee mount was simply to get rid of all the extra strap that I always ended up having waving around in the water. Even when I tucked the strap tails in they would often come loose somehow.

 

[doctormike]

Wow, just noticed this thread, never realized that this was a problem! I have two Petrels, with the stock straps that have the clips in them. Works fine over my dry suit or on a bare arm in the tropics. Never had to ask someone to clip them for me, just put the Petrel face down somewhere, put my arm on top of it, and clip the clips with my other hand.

Is it the extra strap material when you go from dry to wet that is the problem?