When told about my need for a compressor for an airbrush I was considering buying, my grandpa suggested that I get a large, sturdy and airtight air tank, install regulators and filters, fill-it-up at a gas station with the compressed air used for filling tires and use that as an air source for the airbrush.

Though obviously much cheaper than a compressor (and silent!), I'm wondering about the drawbacks of such a system. How much PSI would I need in the tank to last for a good while of airbrushing (2-3 hours)? Would a reasonably-sized tank even last that long? Does anyone here have any kind of experience with this thing? Thanks for any help!

I have done this a long time ago with my canned air. I've used a car compressor to fill it up again. It works but not good enough. Here's how you'll do it:

1. Check how much pressure the compressor can handle. If it can only hold up to 300 PSI, fill it up only up to 270.
2. DO NOT! Overfill it or fill it to it's max capacity. It may explode like a frag grenade.

You'll probably only get 1 model out of a fill At the most... most gas stations only run around 100-120 psi...... a small compressor with a tank would be the best bet.

For whatever it's worth this is kind of the way I use my compressor. I is LOUD, so I don't want to have it come on too often. I fill up the two gallon tank to it's max, about 140psi, then shut it off and move to where I'm going to use it. That amount of air, and that preasure, lasted me laying down the base coat of three models the other day. I may even be able to paint indoors using this meathod, as long as "she who must be obeyed" doesn't mind the smell of the paint.

I use a CO2 tank. It is filled to 900lbs. It is what is called a '20# tank" . It is an easily carried size. At 20psi, I have not made a dent in the amount yet. It will cost about $20 to refill at my local welding shop. Just another idea to think about.
capnjock

That's the same thing I do!!

it would also be a big hassle to run your tank down to the gas station al the time

Thanks for the replies! I have also heard about CO2 tanks over the Internet, is there any key difference between air-filled tanks and CO2-filled tanks aside from capacity (and oxygen displacement from CO2)?

It CO2 tanks are much heavier......they contain Liquid CO2 @ a pressure around 1200psi.

A spraybooth vent (if indoors) & good fresh air supply are Highly Reccomended

CO2 is dry, so a water trap is not required! It is silent and also needs no electricity. The bottle is heavy, but I have mine strapped to a collapsible luggage dolly (the type airline travelers use). It stands next to my spray booth.

FWIW:
I love my new compressor with a tank, and it isnt to noisey.
BUT
the cylinder will give you nice quiet, STEADY pressure.
A lot of compressors that dont have tanks are pushing the air right from the pump, and the pattern can be uneven, I said 'can' not 'are.'
I recommend at least 25psi + when your under load.
Ensure the air tank will do that, and I agree that the gas station pumps may not be able to fill your tank high enough to give you enough air to last a full spray.
Its worth a try but fill your tank on a low humidity day, and use it on a test model first until you 'perfect' this idea.

Wish you the best with it,
Firemann816

I have an airtank I picked up new and cheap at a home improvement center. It needed a little hardware (regulator, adapters), but not much. An airtank doesn't need a water filter because the water condenses out (inside the tank) under pressure. Unless you spray it out to the last ounce of pressure -- and tip the tank so the water washes down to the outlet -- water should never be a problem.

Granted, an airtank does not get as many shots as a CO2 tank, but it is much cheaper to fill (free, if you know where to go in your neighborhood), and is easier to move around.