Not so! Most air tools are rated at average CFM's Ie; ingersoll 1/2" impact 450ft/lbs rated at 9 CFM but will take much more air if working continuously (even 30 sec of trigger time) Cannot measure actual CFM use; just an observation.
A 5hp 60 gallon unit would be minimum that I would use in a low use home shop; reasons
1. Less compressor run time
2. Decreased condensation/water build up
3. Absolutely needed with the following- sanders, grinders, air over hydraulic press, cabinet media blaster.
These tools require much more CFM than a 5hp 60 gal. Unit can deliver at 90psi (single stage, 2 cylinder unit under $1k)
:laughing::laughing:Of course you're right about the
average CFM. My IR231 is rated at 4.2 CFM, but 22 CFM for continuous running under load. But if you need 5 hp and 60 gallon tank, that's fine with me. I've never had to run an impact wrench continuously under load for a long period of time, since I let off the trigger when I take a bolt out or a nut off, and let the wrench quit turning until I put it on the next one. And then it only runs a matter of seconds before loosening the next one. In my shop, I
never needed more than a 3 hp, 60 gallon compressor could provide, even with the cabinet sand blaster, sanders, drills, impact tools, ratchets, etc. - except - the non-cabinet sandblaster. I didn't have an air over hydraulic press; just a non-air 6 ton hydraulic press and a 3 ton arbor press.
Of course now I only have a 30 gallon, 1.8 hp, 5.7 CFM at 90 psi, 120V compressor and had no problems at all taking the tires and wheels off my brother's one ton truck, with that IR231, to do a front end brake job, including replacing one caliper and cleaning the disks with a die grinder. And we were using a 50', 3/8" air hose, and never had to stop and wait on the compressor to catch up.
Of course, maybe your definition and my definition of a "home" shop are different. If I were working in a business where such tools are used all day, every day, I'd certainly want a bigger compressor.