RAM^3 wrote:

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.

That's another issue - just as these consumer-grade air compressor vendors
overrate the CFM ratings for compressors, so they underrate the CFM on their air
tools. I have yet to see an air die grinder which doesn't require a solid 15 CFM
at 90 psi to run the air pump at 50% duty cycle or below which is what you
should have to avoid wearing out your compressor.

Not 6 CFM. Not 10 CFM. FIFTEEN CFM.

GWE