I am looking for a source for underwater electrical connectors. I would need a bulkhead and cable connector, multiple connectors. Want to keep the costs down. Any ideas? Just 12 volt and control signals.
You're not going to get away cheap, I'm afraid.
The cheapest out there are Bulgin Buccaneer connections, available through Newark Electronics. Google for them (add "IP68" to the search) and you'll find them. They work well, but not for things that you want to (1) unplug underwater, as they're not ip68 when not mated, and (2) for things that you want to seal/unseal a lot, as they're fairly flimsy. They're about the cheapest out there, though.
Next up are either Lumberg or Fischer. These are the ones that a lot of the serious dive computers use (VR3, Shearwater, etc). They're expensive - around $50-$100 each, and the suppliers are hard to work with. Usually have to go through a middleman, which adds to the cost, although Lumberg has given me factory-direct quotes and was friendly. Not cheap at all, and neither is waterproof if disconnected.
There's also the route of buying direct from Ikelite - they sell their glands and cables through their dealer network, but the specs are available through their website, and may be a good choice.
If you need underwater pluggable connectors, then E/O is the only way to go. There are a few people who resell them out there, and most of the divelight manufacturers will sell you the cables. Figure on $50-$75 per connector (not pair, but each side.) I have a stash of these lying around that I salvaged from canisters and other projects at a very good price, although mine are two connector. If I needed more, I'd just send serial data on top of the power line for these. They're completely waterproof and can be plugged or unplugged underwater, which is cool. The only downside, besides cost, is that they loosen up over time. Sartek made a clip for them that helps a bit.
Finally, if you really want to cheap-out on this, you can take a look at how Patco builds their connectors for their drysuit heating pads. There are excellent photos on the Patco web site...essentially, they use coax fittings crammed into the same type of an acetal plastic quick-disconnect that you'd normally find on a pee-valve. If you wanted to do a three or four pin mini-plug, you could cram it in there. Not waterproof when disconnected, but would work. I suspect the time wasted to duplicate that at home would be better spent sourcing a proper set of bulkhead/matching bits, and the fact that the metals on the plug would be exposed to salt water regularly in the connect/disconnect/clean cycle of dive year seems like a huge negative point...but to each their own.
Hope these help...
