Pancake compressors modifications



I have an older Sears Craftsman 1.5hp, 4.5 gallon pancake compressor I want to use for airbrushing. I know it's loud but I'm thinking of adding a 4 gallon in line tank to reduce cycling and cut down on noise. Plus it will help cool the air to reduce potential problems with condensation. My question is, with the regulator on the compressor, should I put the water trap on the other side of the spare tank or in between the compressor and the spare tank?
Yup agree with smiler. Or you can buy an extra cheaply from fleabay and have one at both points. My home build has one after the motors, this filters any oil out etc the i have one after the tank to collect moisture from the compressed air, then I have a mini 1 at mybrush
With an inline spare tank, you'll also want to have a regulator on the spare tank outlet rather than using the one on the compressor. If the compressor has a built in regulator, keep it all the way open, and use the one on the spare tank outlet to actually control your air. If there's no regulator downstream of the spare tank, the spare tank can't build pressure like you want.

Your basic airflow order should be like this:

Compressor --> hose --> tank --> regulator --> trap --> airbrush hose

With a single trap, the trap should be the very last thing before the airbrush hose, with the regulator second to last.

If using two traps, your airflow order should look like this:

Compressor --> hose --> trap --> tank --> regulator --> trap --> airbrush hose

Note that the first trap is at the tank inlet after the connecting hose, not at the compressor outlet. This is because the connecting hose acts as a condenser, making the trap more effective if it's placed here instead of right at the compressor outlet.

In the same vein, if your work surface is more than a conservative arm's length from the tank, it's a good idea to put another connecting hose between the spare tank and the regulator/trap block. Ideally you want the regulator to be attached to your workbench or easel or whatever else you can easily adjust it without stepping away, turning your body, bending over, or otherwise leaving your work. In which case:

Compressor --> hose --> trap --> tank --> hose --> regulator (benchmounted) --> trap --> airbrush hose