I used a pressure switch off of a household well water pressure tank. Got it at the local plumbing supply store. I used a pressure switch that turns the compressor on at 40 psi and off at 60 psi. For now it is hooked up to a little compressor that came inside of one of those roadside assistance kits, but I'll save some pennies until I can afford a "real" 12v compressor. But that's the fun of this hobby - making stuff work using whatever (safe) means possible.

That original box and instructions is way cool too.

Craig

It is neither wealth nor splendor, but tranquility in occupation which brings happiness. - Thomas Jefferson

CK