Scuba tanks for C02?

fretman124 · 04-23-2007, 02:44 AM

I have two aluminium 80's (80 cu ft ). These are 3000 psi tanks. They will need hydro and vis inspections. Since I don't dive any more, could they be used for C02? If so....I just saved a bunch of money The neat thing is they are custom painted and have flat bottoms..................

**Jaybird** · 04-23-2007, 02:52 AM

I really dont think so but I would be willing to buy one from you for paintball my gun shoots only compressed air.
Jay

fretman124 · 04-23-2007, 05:45 AM

TTT

Any more opinions out there?

z987k · 04-23-2007, 08:41 AM

I don't know for sure, but I don't see why not. I don't think co2 tanks get close to 3000psi so it's not a strength issue.

**Bobby_M** · 04-23-2007, 12:46 PM

You'd just need to replace the valves. I don't think they make Yoke/DIN converters for CO2 regs.

Ol' Grog · 04-23-2007, 01:44 PM

I don't know if the welding shops would fill a SCUBA tank.

**Bobby_M** · 04-23-2007, 01:47 PM

It's a tough call. I don't know what their regulations tell them to do. If you use common sense, if it's good for 3000psi, it's probably good for 800. I wonder if the bore/thread in a scuba tank is the same as CO2 tanks. What I mean is, can the valves be easily swapped? If I were you, I'd sell both tanks on Ebay (probably get $60 a piece) and just buy a used Co2 tank.

**the_bird** · 04-23-2007, 01:55 PM

I didn't think you'd be able to get them to fill a scuba tank with CO2 just 'cause of the potential liability if someone thought the tank was actually, you know, filled with oxygen and used it when they dove.

**Bobby_M** · 04-23-2007, 04:22 PM

That's why tank labelling is so important. Then again, if you replace the tank's valve with one that works with a CO2 reg, there's no way to attach a scuba reg anyway. No way you'd breathe it. In any case, you can fill a scuba tank with anything from 21-100% O2 and it can be lethal if marked incorrectly. I.E. breathing 100% O2 at a depth of 30+ feet will likely kill you from a blackout.

JimC · 04-23-2007, 04:53 PM

Scuba tanks can hold all sorts of stuff that would kill you if used improperly. From 100% O2 will will send you into toxic shock to hypoxic trimix that doesn't have enough oxygen to sustain life (less than 17%). Simply put, breathing a scuba tank you personally did not analyze the contents is not smart. Ever. Even if its just supposed to have 'air' in it. Even if you aren't even in the water.

However, scuba tanks (mostly) have 3/4-14 NPSM and C02 tanks have (mostly) 1.125-12UNF-2B threads. You need a CGA 320 on the outlet side of the valve to screw the C02 Regulator in. There is no such thing as a 3/4-14 NPSF to CGA 320 valve that I know about. You can however get adapters for DIN and A-Clamp scuba to CGA 320 which would allow you to hook it all together off a regular scuba valve from places that deal with painball or technical diving.