SpudFiles

Okay so I've gotten an empty fire extinguisher tank and I'd like to make it into an air tank with a schrader fill and a ball valve. I've already figured out how to do the fill and the ball valve. I'm using 3/4in steel pipe and a T junction for 3/4in steel pipe. But now how do I attach it to my tank and what sort of air pressure can I put in it? I've looked it up and haven't come up with much so I figured I'd ask you guys who know more than me, so I don't wind up hurting myself. I'm planning on using it for a BBMG.

Many Thanks

a pic may help, normaly fire extinguisher takes about 13 bar, that's what i saw most, but there are also extinguishers that takes about 28 bar and some times a impressive 200 to 250 bar. holp this helps

The CO2 extinguishers are rated crazy high, some Halon extinguishers may be rated to around 600-800, but mine is only like 160. Everything else has a WP from 160-250 PSI, in general.

I believe propane tank safety valves trigger at around 300 PSI, so that may be a good option.

Here is mine, to connect it to the gun use a quick connect fitting.

I put anywhere from 120 to 180 psi normally in mine.

Here's a picture of the threads of my fire extinguisher canister.

What is a quick connect fitting?

@Gunfreak
Where did you get that regulator valve?

Have you already figured out what thread size that is? I reccomend JB Welding the fitting in if it is not perfect.
A quick connect is the fitting on like compressor lines that let you use different tools without unthreaded them all. You push the tool on to connect and pull the slide to release it. You can buy them cheap at home improvement stores in the compressor section.
The regulator is a messed up one from my compressor that I tried to use after we got a new one. You can buy them for like 20 bucks at home improvement stores, or get a flow control valve which doesn't regulate pressure rather how fast air goes by.

Usually FEs have threads that are just a little too small to accept 3/4" NPT fittings, but a trick to adapt them to normal threads is with an sch 80 pipe nipple. This works because unlike steel, the PVC can be cut into by the existing tank threads. You'll have to force it in, but it'll be air tight and epoxy free

Or just use the fitting that was origianlly in there and tap new threads in the middle like I did.

That requires a pipe tap and epoxy, which he may not have since he is new in this hobby.

HunterT, that looks exactly like the one I have. any PVC threaded fitting will thread into with a little effort. So far, I've put 200 in mine, and I'm comfortable with taking it to 300 based on the solid construction and concave surfaces.

You guys are lucky, the threads on mine were strange. That is probably the weakest spot on my tank.

Gun Freak, I'm absolutely positive that our FEs are identical, and you could have used a similar setup. I can take a picture if you like, but its nothing special

Yeah, they look similar, sure. I'd like to see your setup.

my FE has threads extremely close to 1/2'' bsp i put a bit of epoxy on the pipe nipple and iv been using it for 1 1/2 years usually at 350 psi.

I still have the original fitting and I can tap threads in, but how much pressure can it safely hold? I was also thinking about putting some JB weld on it too. I should probably add, the threads on my tank are weird. They're like threads on a wide mouthed water bottle. Not at all like normal threads.

If your planing on using it for a bbmg, I would recommend a CO2 tank instead. They can easily hold 800psi (a good bit of air) and can be dialed into what ever psi your going to use in your gun with an inline regulator. The fire extinguisher tank might be better used in a different project. Bbmg's EAT air... and though that bottle is decent sized @300psi it isnt gonna last that long.

tank
http://www.zephyrpaintball.com/product/ ... -Tank.html

regulator
http://www.zephyrpaintball.com/product/ ... Black.html
notice the MAX input- this is the psi of your tank... and the adjustable output-this is how much psi is going to your gun. Regulators are GREAT because you can change how hard your gun shoots... less psi in the gun makes it acceptable to use with friends, more psi in the gun makes it KILL thing (paper/alu. things). You get all of this control WITHOUT having to change how much pressure is in your tank.

Also, since its using standard paintball gear (ASA fitting and 1/8"pt) you have the option of mounting it to the gun... or having the tank in a backpack via remote line.
http://www.zephyrpaintball.com/product/ ... Check.html

note: all links are for demonstrative purposes only... all items can be bought MUCH MUCH MUCH cheaper thru e-bay or more intensive online searching.