Air compressor sizing

[2Biz]

I've used a 110V piston compressor as a backup plugged into the large tank and she keeps up fine.

That pretty much tells the tale. Most CW compressors are way oversized. I have a Campbell Hausefeld 80 gal 6hp compressor for my 4 bay. Probably 20+ years old. Since the most pressure I need is about 60psi, on is set @ 80psi and off is 100psi. This helps minimize heat buildup and moisture. With the 80 gallon tank, I rarely hear it kick on. Control the leaks and it dramatically changes the size needed and the cost to operate.