"Don Foreman" wrote in message
news

Ignore the HP ratings. The only meaningful rating is free air CFM at
90 PSI. There are a few "consumer" 5 HP units that will deliver
about 11 CFM at 90 PSI. They're OK for occasional use, and they will
run most tools including a diegrinder, DA sander, chisels, sprayer,
impact wrench, etc.

I'll second that and suggest ignoring any unit that can't produce at least
12 CFM @ 90 PSI with at least a 20 gallon tank.

I bought a Porter Cable "Job Boss" [model 3151 iirc] that was "rated" at 6.2
CFM @ 90 PSI. It won't keep up with a Campbell-Hausfeld 6 CMF die grinder.
Oh, it'll run it for a short period but not continuously and a sander is out
of the question.

If you have any desire to do any sand/bead/shot blasting you'll need up to
30 CFM.