This is from a post I made last year, but basically it's a long piece of copper tube in an exaggerated upside-down "U" with an inlet near the bottom left and the outlet near the bottom right. It's not a "proper refrigerated dryer" but my air during the Florida summer - where humidity exceeds 95% every night for 6 months at a time - is as dry as it ever was with a big industrial chiller desiccant dryer inline.
We also got a proper second test of our home-brew moisture separator, which is the big copper apparatus standing up by the air compressor. It's a 10' stick of 1/2" copper, cut into two pieces 4'10" long, and connected together with the remaining 4" of copper and some 90s, and soldered together. There are NPT adapters on the bottom with drain petcocks in both sides, and the air inlets are soldered into a T about a foot off the bottom. The length of copper forces the air to condense and, believe it or not, it actually works PRETTY DAMN WELL.
The black Sanborn compressor came from (I'm pretty sure anyway) Builder's Square sometime in the nascent years of the Reagan administration, and when the motor died on it during the Clinton years, it sat in my dad's garage until ~2011. The Craftsman tank seized its compressor in '08 but the motor was still fine, so with a little cut and paste we got the whole thing put together and it works great. Only minor issue is that the compressor head itself gets a little warm (>300F) when sandblasting for hours at a time, so there's a small axial fan mounted up above the outlet blowing forced air on it and now it runs <200F for as long as we care to use it.
My #1 suggestion, if you have the capability in your garage, is to go with a 240V unit.
Official photographer/Team Police Brutality|Speedycop & the Gang
Lackey-mechanic-whatever/NSF Racing
Sycophant/Judge Phil, Jay Lamm, Kim Harmon
Galaxie Driver/not Parnelli Jones