The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post

Dead Parrot · 03-25-2020, 08:08 PM

Find some way to inspect the tank on grandpa's compressor before using it. If it sat a few years before you got it with water in the tank, you could have a potential bomb if you ever get it to pressurize. Probably not the legacy grandpop would like to be remembered for. The smoke could be grandpa looking out for you.

One way to think of compressors is:
Size in Gallons + Max Pressure = battery.
CFM rating on pump = charger.

More of either raises the cost.
High enough CFM can lead to a need for a special 240V drop for the motor.

Most tools want 90psi at some rate of flow. As long as your regulator and hose can handle the flow, even a small unit can power a large tool, just not for very long before your pressure starts dropping off due to low air in the tank.

I currently have a 30 gallon 2HP twin cylinder single stage unit I got from Northern Tool as a refurb. If I do a long run with a small angle grinder, it will run low on air. Doesn't happen often enough to justify a larger higher CFM unit. If you are going to do painting, might be worth while to get a similar compressor pump mounted on a 60 gallon tank.

As others have said, the compressor is just part of the equation.

03-25-2020, 08:08 PM	#7
Dead Parrot Registered User Join Date: Aug 2012 Location: Oklahoma City, OK Posts: 2,484	Re: Advice or input on compressors Find some way to inspect the tank on grandpa's compressor before using it. If it sat a few years before you got it with water in the tank, you could have a potential bomb if you ever get it to pressurize. Probably not the legacy grandpop would like to be remembered for. The smoke could be grandpa looking out for you. One way to think of compressors is: Size in Gallons + Max Pressure = battery. CFM rating on pump = charger. More of either raises the cost. High enough CFM can lead to a need for a special 240V drop for the motor. Most tools want 90psi at some rate of flow. As long as your regulator and hose can handle the flow, even a small unit can power a large tool, just not for very long before your pressure starts dropping off due to low air in the tank. I currently have a 30 gallon 2HP twin cylinder single stage unit I got from Northern Tool as a refurb. If I do a long run with a small angle grinder, it will run low on air. Doesn't happen often enough to justify a larger higher CFM unit. If you are going to do painting, might be worth while to get a similar compressor pump mounted on a 60 gallon tank. As others have said, the compressor is just part of the equation.