Air Compressor Size Question, How big is big enough? Options

[BeatNavy]

This may have been covered before, but I did not find it answered explicitly:

What size air compressor is good enough for doing a decent quality paint job on our cars and otherwise work with air tools? I don't have one now, but I am thinking of making the plunge and trying to paint my car at some point. I don't think I would really do anything bigger than a 914.

Here's a more specific question: is a 60 gallon, 3HP, 11.5 CFM at 40 psi; 10.2 CFM at 90 psi good for this? There's one on CL not far from me that could be a decent deal and serve as my post-Christmas gift to myself.

[bbrock]

Great advice on size. I will add that I would avoid an "oil-free" air compressor. When I started my build, I bought a barely used 60 gallon, 6 HP Devilbiss Pro Air II with killer cfm specs. I didn't know anything about oil-free compressors. Right off the bat, the thing seemed to have slow recovery times so I rebuilt the pistons. That didn't change much. Nevertheless, that unit got me through all the cutting, grinding, spraying primer, and even sandblasting the entire car, but I spent a LOT of time waiting for the compressor to catch up. Despite trying to be careful to keep it to a 50% duty cycle, recovering times got worse and a second piston rebuild was completed (About $50 per cylinder for parts). Finally, the compressor literally blew up, sending a shattered piston top into the head. Huge waste of money.

I now run a 60 gal. 5HP 2-stage compressor and and am MUCH happier with it. As others have said, it is more than enough for lower consumption tools and paint sprayers. It is adequate for blasting, but requires waiting for it to catch up to keep the duty cycle reasonable.

I think for most DIY occasional use guys, the 60 gal. 5HP 2-stage is about the sweet spot. You can do a lot with a smaller compressor, but you can also nurse this size through occasional more demanding tasks that smaller units couldn't handle. For example, when I have a lot of cabinet blasting to do, I try to set up one or two other projects that don't require air to switch off to while the compressor is catching up and getting a rest.