air compressor size????

One of the most misunderstood and incorrectly advised and described areas of the hobby.

67dart273 is 100% correct.

CFM trumps all other ratings. Period. Unfortunately it's the most difficult rating to find.

5+ HP, iron head, and belt drive are good clues that you are looking at a quality unit.

Also be wary of unrealistic HP and amperage ratings. A 6HP motor is not going to draw only 20 amps. Start and run draw are also different.

I was recently searchng for a secondary/portable unit, and the Highest CFM 110v unit I could find was a DeWalt/Emglo 2HP, 8.4 CFM. It will run my blast cabinet, but just barely. I paid $300 used, but they are over $800 new.

Don't be afraid of a good quality (Quincy, Bel-air, etc) used unit.