Scuba tank to power air tools?

[Flot]

Guys, sorry if this is a little off-topic, but any good DIY solutions for using my scuba tanks to run garage air tools?

I don't really need a compressor but borrowed a buddy's air nailer last weekend and whew it was nice.

Since I have a garage full of air tanks (well 4 alum 80s) it seems like there should be an easy way to tap into this. Has anyone done it / can you point me in the right direction?

I think I will need:
- old 1st stage to output ~120 psi?
- some kind of adapter
- air tool pressure regulator to let me adjust the 120 psi down if needed

Thoughts?

 

[Tom Winters]

I ran an air tool reg plugged into a bc hose to paint boats. Worked great even running off a 50' hose. Nice clean air. If you're going to do much pneumatic stuff, air compressors have gotten pretty affordabe - Amazon has some unreal deals every few months or so.

 

[300bar]

No problem get an old balanced membrane 1st stage
go to your local diy store and get a female quickconnetor
and you are in action.
I'm doing it for a few years now stapplers,drills,hammers,paint spray
Works fine and no compressor noise.

 

[DA Aquamaster]

An old conshelf first stage is almost ideal. It;s easy to adjust the spring pad tension with a screw driver so you can run it at 140 psi for max flow rate with power tools or you can adjust it as low as 10-20 psi for use with an air brush. They tend to be very cheap on e-bay and require very little maintenence.

 

[ClevelandDiver]

1/4-Inch NPT to BC inflator

http://www.diveriteexpress.com/regs/hoses.shtml#adapter

 

[pescador775]

I have been doing this, using scuba tanks for air source, for 20 years. The reducing valve is the first stage of an aqua master regulator. The aqua master is adjustable, has an 1/4 inch oxygen fitting and a pressure relief (second stage poppet)which is set to about 150-160 psi. The hose is a ten foot oxygen hose with 1/4 inch O2 fitting and other end is #4 JIC. The hose's female JIC (tapered fitting) is screwed onto a male JIC fitting which in turn is fitted into a female automotive type quick disconnect. All my air tools are equipped with the male quick disconnect as are my air gun and tire filler stick. Have the welding shop make up a hose with the oxygen fitting. Go to hydraulic shop for a -4 JIC female. Buy the quick disconnects from auto supply store. If you use a conshelf, you will need a dive-rite relief valve. Also, you will need a JIC-3 boss fitting on the regulator side of the hose. This will screw into the conshelf LP port. If you can't find a boss fitting, buy a cheap -3 male taper fitting and cut off the end. Carry the hose to the hydraulics shop, explain it is for low pressure service and examine the fittings to see which one will fit in the hose. Stick the fitting into the oxygen hose and fix with a small hose clamp. You will also need an O ring. If you wish to simplify the connection on the quick disconnect side of the hose it is not necessary to use the -4 JIC female and male. Simply insert a hose barb into the hose and clamp. The hose barb should be of the right size to fit 1/4 inch oxygen hose and also have 1/4 inch pipe thread to fit properly into the female quick disconnect. Your hydraulic shop will have this fitting.

 

[Flot]

Thanks for all the replies guys - I'm a bit confused as to the variety of the answers (which seemed to be anywhere from 2 parts to 300 parts (pescador??? lol) but it sounds like this is very do-able.

I find a use for an air tool maybe once a year, and don't have room in my tiny garage to have a compressor, but sounds like dive tanks are actually a pretty reasonable option. \ I'm concerned that some air tools have continuous ratings of using as much as 20 cfm... would that tool really only last for 4 minutes off a tank? (and maybe that isn't so bad after all?)

I'll check out this 'conshelf' 1st stage... could someone elaborate on why this particular model is more desirable? I'm assuming that for fine pressure regulation I'd be better off getting some kind of air tool regulator and attaching that to the LP port?

 

[pescador775]

Stop right there. Don't get an air tool regulator. The Conshelf is cheap, compact, reliable and is a balanced system. The only drawback is no relief valve. Are you a diver? I shouldn't have to explain about that. If you have a "20 cfm" air tool, you must have plenty of room in your garage after all. That's enough air to blow a man off his feet. A standard Scuba tank will be enough to remove and replace four automobile wheels with no problem, and have power to spare. An air nozzle will last about 10-15 minutes continuous stream. Don't worry about "fine setting". Set the Conshelf to 110 psi and leave it. Adjust the pressure with a coin held in a vice grip. A screw driver will damage the capscrew. If you don't have a gauge, back off the Conshelf capscrew by one turn and try it. You MUST have a long hose in order for the setup to be useful. If you have questions about specific items, I or somebody can answer it. I can't answer "philisophical" questions about whether this is a good idea but too hard to understand. However, for the average guy this setup can be very useful.

 

[Flot]

Pescador I'm a diver, I'm not an air tool guy. I borrowed my first air tool (a nailer) the other week and that's what got me thinking.

I realize the tank will be a-ok fine for nailers, impact wrenches and the like. I was just curious about continuous use tools like paint sprayers, grinders, etc. (which, as I understand it, can have very high cfm requirements?)

I also thought that external pressure regulators were semi-common for air tools, so rather than try to track down a specific easy-to-adjust 1st stage I could prob just go to my local dive shop and offer them $10 for some old piece of junk they might have lying around...

 

[pescador775]

Pressure regulators are common for air tools. More than likely they will explode when connected to a scuba tank. Pressure regulators are common for welding. More than likely, they will not supply enough cfm to blow out a candle; that is, unless you buy a nice, expensive two stage. There are single stage pressure reduction regulators which will work at high pressure but you will need a hand to hold while exporing the junk yard. Neither type will have a yoke connection for a scuba tank. Neither will have a relief valve. For historical interest, old 1st stages which had tilt valve seconds also had relief valves. One example is the Voit single hose regulator from the 1960's.

An old junk scuba regulator might work OK. However, air tools usually operate at about 100 psi. All of the old diaphragm first stages were adjustable. Mares and Conshelf are examples. Some regulator 1st stages operate at 140 psi so need to be adjusted. If the first stage valve fails (leaks), the hose could explode or the attachments could end up in your neighbor's yard, your neighbor on the other side of town that is. I can send you a relief valve, free; but it uses 1/4 inch npt. You would need a T connection or whatever.