Well I have been looking at ways to get OBA. I have seen the complete CO2 set ups for around 300-400. Has anyone built there own system with a 20CF bottle and regulator? I have search everywhere and only found two write ups, but they dont list what regulator and such they used. Also is there a way to use a scuba tank and put a regular welding regulator on it? And wouldn't nitrogen be a better gas to use. I've heard that CO2 can bleed off were as Nitro doesn't plus nitro is actually better for tires. And would I be able to buy a name brand regulator designed for OBA ( http://www.offroadair.net/products2.html)
and put it on a regular 20 CF tanks. So many questions.

Any thoughts on this would be great!

Yes you can make it work. Simply buy a CO2 tank of your choice, and then buy a regulator (such as the offroadair unit), and then buy some coil hose capable of like 200psi, and you are done. Do not use a SCUBA tank, it is dangerous, very compressed. If you knock the top off, it will be a rocket. Anyway, I know for a fact that this was covered VERY in depth, because I just recently looked it up.

Look here: http://www.pirate4x4.com/forum/showthread.php?t=84702

Thanks, I looked on google for about 2 hours, no surprise that I should have check here first

Yea I always check here first. Anyway, it should be A LOT cheaper this way!

It didn't really say but are the powertank and a regular regulator interchangable?

Are you planning on buying the Powertank cylinder and then buying a regulator seperately? Because the powertank cylinder is way overpriced. You can go to a welding supply shop and buy a CO2 cylinder there for a lot cheaper. Unless you want the cool powdercoating of the Powertank. If you just plan on using the tank for airing up, I would recommend you get the OffroadAir 150psi fixed regulator for around $35, and then buy a CO2 tank from a welding supply shop, and then get a 200psi coil hose from Lowes for like $10. That is probably the cheapest way to build a CO2 setup. And yes the regulators are interchangeable between CO2 cylinders.

No, i was going to buy a 20 CF welding tank and then was hoping to buy the regulator you where talking about. What would you recommend for a tank? a 10 or 20 CF?

Depends how much room you got in your truck. I have a 10# tank, but I got it for free so it wasn't a real difficult decision for me. It all depends how often you plan on using it and if you have the space. I would go with a 20 if you can fit it, but if not, a 10 will be plenty capable. Also, check the price difference when you go to the welding supply shop, that might make your decision easier.