Caber
Aanyone know of a cheap source of air tanks to increase the capacity of my compressor? in the USA you can buy tanks off the shelf for compressed air
storage I haven't seen any here.
Caber
Scrapyards that break commercial vehicles will have them.
I made a "pony tank" (euphimistically known also as an "air pig" around these parts) out of a couple of discarded 20 lb. barbeque
propane tanks. Joined them together using a manifold of pipe (threaded on the ends) with an air-tool type quick-connect and a cheap guage in the
middle. Works a treat - holds enough air to completely inflate 4-6 large, flat tires. Or, to run an air-impact wrench long enough to remove and
replace 4 large truck wheels. I flushed out the tanks with hot water and soap first (until the smell was gone). Although fuel gas fittings are
usually left-hand thread, the thread going into these tanks (after you unscrew the valve) is normal, right-hand thread. VERY cheap, Locost way of
doing it!
Not sure about propane tanks, I don't think they are rated to high enough preasure (at least not in the uk)?
Cheers,
Dan
they are surely? Can't remeber what it says on the bottles I have but I am sure its over 250 psi.
Anyway, unless you can find some old bottles that have been open for ages I would rather go for a helium bottle or similar.
Go to your local tip and ask what they have, ours have loads of different bottles that they will give away.
Must be thinking of butane... Like you say so long as it's rated to the correct preasure, should be fine, but I would also agree that a bottle
that has had inert gas in it would be a safe option if it's in good condition (no idea how you know that mind!!).
I think the standard tests use water to preasure test the bottles above there nonminal rated preasure. Not somthing you can do at home.
I would be cautious with a scrap bottle, after all why was the bottle scrapped?
You can get external tanks in the UK that are preasure tested, not locost though...
Dan
[Edited on 10/10/06 by Bluemoon]
The bottles at the tip are just stuff people have found in sheds, on gippo sites or in the corner or their workshop.
If you are worried about the pressure thing then get a big high pressure gas bottle, again from the tip, like an old oxygen or nitrogen bottle. These
aill stand at least 20 times the pressure you need them to!
Older oxygen type bottles which are obsolete were filled to 200bar (about 3000psi) whereas the new ones are 300bar. Propane bottles (the ones I have)
are tested to 34.9bar in case they get heated but are only rated at about 90psi for continuous use as they are designed to contain liquid gas not
pressurised according to my caravan bottle supplier.
[Edited on 10/10/06 by Peteff]
quote:
Originally posted by Peteffare only rated at about 90psi for continuous use as they are designed to contain liquid gas not pressurised
What about an old non-working compressor? Assuming the reason it doesn't work isn't that the tank leaks 
Have a look on ebay.
A 222 litre one ( roughly 6ft high by 2ft wide) just went for £77.
I listened to my gas supplier. I trust him more than the internet when it comes to gas cylinders. My compressor runs to 150psi and is a basic sip one.