gas switch connectors...

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Jeff Pack
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gas switch connectors...

Post by Jeff Pack »

I'm getting my GEM setup for gas switching and there seems to be some dispute on the connectors I should be using.

Some folks state its ok to use BC connections, others the omni swivel locking type connectors. (Of course some say to hot swap, and not use a gas switch block, but thats another entirely different story).

Any collective wisdom? For the moment since I had a bunch of spare bc/drysuit hoses, I put them on my bailout and deco bottles.

The OmniSwivels pass more air, but since they are the same as on my GEM regulator, are an SOB in the water to ever disconnect.

I've read a few folks use the swagelock QC6 connectors.

thx!
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CCR discussion on Caustic Cocktails.
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CaptnJack
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Re: gas switch connectors...

Post by CaptnJack »

The flow rate on the BC connectors won't be adequate for you to go open loop, esp at depth.
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camerone
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Re: gas switch connectors...

Post by camerone »

The lack of reasonable flow out of a standard BC nipple may or may not be a concern on your rebreather, unless you're using it to plumb in the BOV and going full open circuit with it. That said, I agree that it's probably a bad choice for you :)

A _much_ better choice is the CEJN fittings common on Poseidon and Viking drysuits, amongst others. They're a much higher flow fitting. You want the 221 series. Northeast Scuba Supply has lots of the parts: http://northeastscubasupply.com/store/i ... a=category I think you'll find them to be a more standardized item in the scuba community than the other ones you suggest. They're bored for breathing gas - in fact, Ocean Reef uses them to supply some of their full face units, and it's pretty easy to get off-the-shelf drysuit hoses that fit CEJN nipples, which you have a better chance of in some places. I might pick up a couple of the 2nd-stage->CEJN adapters, though, and keep them in my save-a-dive kit, if I were you.

That said, I use an OmniSwivel system on my BOV, but you're right - once pressurized, they're a pain to work with. I'm also not sure that you need the twist lock capability that they provide. The only place I have this is on the BOV because it's on my on-board diluent, just for three sanity breaths until I find a bailout bottle or decide to go back on loop. Need the flow, but don't ever want to risk popping it off under water...'cause when I need it, I need it.

I'm planning on swapping to BMCL on my franken-Evo soon, and I'm not going to use the lung injection for gas; I've decided to plug the remote counterlung port on the APD lungs and just plumb directly into the scrubber for the manual adds instead. So, I have to make an offboard gas choice myself... I'm going to use a BC nipple for it, but that's because I will not plumb it to the BOV circuit...so the flow rate required to run the loop, even in SCR mode, is much lower than what you demand.
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Jeff Pack
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Re: gas switch connectors...

Post by Jeff Pack »

My bail out bottle will always have a reg on it anyways I'm thinking, so that'll be my BOV on a necklace, as well as a QC fitting to hot swap into my loop if so inclined or needed. My deco bottle and back gas will be on the switchblock. I'll still yet have a reg off my BG as yet even more redundancy if needed.

I'll look into the CEJN connectors, I read about those abit on RBW.
=============================================

- I got a good squirt in my mouth
- I would imagine that there would be a large amount of involuntary gagging
- I don't know about you but I'm not into swallowing it

CCR discussion on Caustic Cocktails.
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kdupreez
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Re: gas switch connectors...

Post by kdupreez »

What about those quick disconnects they use on Air2 BC inflator and reg combo?

You get those that will thread onto a standard reg lp hose and provide more than adequate flow.
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Jeff Pack
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Re: gas switch connectors...

Post by Jeff Pack »

got a few of the CEJN fittings coming from northeastscubasupply.com and an omni swivel gas switch block on the way.
=============================================

- I got a good squirt in my mouth
- I would imagine that there would be a large amount of involuntary gagging
- I don't know about you but I'm not into swallowing it

CCR discussion on Caustic Cocktails.
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