i found a 15 gallon air compressor at wal mart. very decent price. 188 bucks for it. i was wondering if its big enough to paint a car? i dont want to have to wait or go slow because it wont be able to keep up. it has a 2.5 HP motor i believe.

 

depends on the volume your gun uses and how long you plan to pull the trigger at any given time. I would say its a bit small to easily do a car but I have seen people do it with smaller and just paint a strip then wait, paint a strip then wait. Some paints dont mind this, some paints hate it.

The average gun set up will consume 15 cfm at 30 psi with an average sized fluid tip. The average 15 gallon compressor with produce 8 cfm. So you can make the fluid tip and air cap smaller and flow less paint and require less air but you also risk drying out the paint or not atomizing enough and getting an orange peal finish. So then you can add flowtrol or similar get the paint to flow out better.


Another option is to go with a gravity fed mini gun like a sharp sgf-98 with a 1.4mm tip (good for medium grade automotive paints) they only require 8-11 cfm at 40 psi

or a sata minijet for 2.8 cfm at 30 psi but thats with a clear coat nozzle set up.