On Oct 2, 7:10*pm, dpb wrote:
Blattus Slafaly wrote:
wrote:
...
...1.5hp 4-gallon @90psi *air compressor. *...
...
Your compressor may give you 30 seconds of impact wrench time ...

Well, 4gal -- ~0.5cu-ft and a typical 1/2" impact wrench will need
roughly 5 cfm@90-100psi (I was thinking of the big 3/4" jobbie earlier
needing almost 9). *So, not accounting for any losses at all would be
about 1/10th of a minute (6 sec) and poof!--tank's empty.

I really doubt if he'd get it to spin up to speed even, what more
actually make an effective impact.

--

Don't knock it 'til you've tried it. My twin hammer Porter-Cable works
just fine with my Hitachi twin tank portable (1.5 gallon, or whatever)
set at 110 PSI. The OP stated 135 lb-ft torque is reached by many
impacts in less than two seconds. Calculations are trumped by actual
facts every time.

Joe