PVC / ABS Canister Questions

Hi, im going de cheap way for the Can of my canister light.

And im concern about the seal and water entry.

What is a combination of fitting that already known good.

Im tinking using a screw type end cap (the one with a large o-ring) on one end, and a regular glued to the other end.



It will be all made of 3'' piping

That should work. Those fittings are designed to be water tight.

They aren't, however, designed for many open-close cycles. I haven't seen one with an o-ring like you show, that should help with multiple operations, if you lube the o-ring with something compatible with both the o-ring and the plastic. I'm no expert but I'd guess that the silicone grease available in dive shops should work. Oxygen-safe products like Christo-lube should also work.

The normal solution for a canister light is to take something like you show, strip the threads and use cam buckles to hold the top to the body and compress the o-ring.

Those kind of fitting are very commun here in Quebec, Canada. They sell them in every hardware store.

I think i will cut the plastic square on the top and glue a sheet of plexiglass, so i will have a nice flat top to put my switch and the gland connector

Have you thought of using an Otterbox for the canister? They're cheap and don't have to worry about fitting the latches to PVC/ABS. I've been down to 100 ft and so far so good.

Also, I can't see your picture.

beekeeper5 said:

Have you thought of using an Otterbox for the canister? They're cheap and don't have to worry about fitting the latches to PVC/ABS. I've been down to 100 ft and so far so good.

Also, I can't see your picture.

Click to expand...

Putting a reinforcing frame in side a otter box can help greatly as well.

Benoit said:

Hi, im going de cheap way for the Can of my canister light.

And im concern about the seal and water entry.

What is a combination of fitting that already known good.

Im tinking using a screw type end cap (the one with a large o-ring) on one end, and a regular glued to the other end.

It will be all made of 3'' piping

Click to expand...

Matey - not sure about canadian fittings, but here in aus i have used 50mm threaded end caps. (brand is called "ipex")
they work fine as long as you replace the one that came with the cap....its too hard and too small....
i got some 3mm thickness nitrile ones and lubed them heavily - they have worked happily to 25m.

we don't have 75mm - but if they are anything like the 90mm ones we have here,
don't use them....they are too flimsy and the threads are very innacurate...
so they are hard to get on, hard to get off, and its difficult to see how they could stop water getting in.
(the large end caps are not really designed to hold water - their intended use is an inspection port in a low-pressure application)
they are also designed to keep water in - not keep it out, so the pressure is on the wrong side.
I get away with it on the 50mm stuff due to the low surface area of the seal.

Here's kinda what i am talking about

http://www.fishingworld.com.au/news/practical-diy-pipe-projects


This one here is a better design...

http://www.scubaboard.com/forums/making-your-own-gear/311236-pvc-canister-am-i-crazy.html


Good luck!