Here's my home-made water separator for compressed air. Used it once to bead blast and sand blast with no condensation issues. Air blasted out of an air nozzle after going thru the separator doesn't have any noticeable water drops in it. Think its solved my problems.
Picked up a 5 gal portable air tank ($20) from Tractor Supply, 20' of 5/8" OD copper tubing ($40), and some pipe nipples and fittings. The separator is placed in a plastic tub (same one I used for electrolytic rust removal) and covered with 4 bags of ice to chill the compresed air and condense the water vapor.
Air from the compressor goes into the top of the copper tubing coil, is chilled as it goes around the coil, goes into the tank at the bottom of the coil, and out of the tank at the top. Both the coil and the tank are covered with ice and act as heat exchangers.
An 1/8" pipe is connected to the bottom of the tank and run up the outside to a small shutoff ($5) like the one used on the supply for a toilet tank or sink faucets. Opening the valve at the top of the 1/8" pipe allows any collected water to be forced up the pipe and out. Holes were drilled and fittings welded onto the top of the tank to accomodate the air exit and into the bottom for the water drain.
Black iron fittings would have made for decent welds -- just weren't available where I was shopping. I had big-time problems with the galvanized. I welded galvanized before without any big issues but not this time. Even after grinding off the layer of galvanizing, pin holes would develope right thru the fittings. Anyway, it ain't pretty but its done and it's functional. Like always, I could do it better the second time.
