60 gal compressor garage piping size.

[67C10Step]

I've got some cheap version of rapidair in my shop to have three hose connection. It has worked well but probably not as good as the rapidair system.

Also, I have dealt with compressed air systems professionally quite a bit in almost 30 years working industrial stuff. I was asking a certified expert once on line size and his response I will never forget. He said, "Nobody has ever complained about an air line being too big, but they always complain about the ones that are too small."

It comes down to economics for the most part. A 1" main system with 1/2" to 3/4" drops should run most hoppy shops.