ModelRailroadForums.com is a free Model Railroad Discussion Forum and photo gallery. We cover all scales and sizes of model railroads. Online since 2002, it's one of the oldest and largest model railroad forums on the web. Whether you're a master model railroader or just getting started, you'll find something of interest here.
I knew it would happen, it just occurred sooner than I expected. Lowes has lowered the price of the small 1 gallon compressor to $49.97. Its item number 98945 if you're interested.
The pressure setting is determined by the type of paint and thinning ratio that you use. I normally paint with Scalecoat II thinned at 50% and set the pressure from 20 to 25 psi. For weathering, the thinning ratio is closer to 75%, and I increase the pressure to around 35 psi because I like the "dusty" effect I get. I usually spray (thinned) acrylics at 10 to 15 psi. I haven't used Floquil, so I don't know what pressure to start with for their paints. Generally, start with the manufacturers' recommendations, then experiment till you get the results you like. You can paint (and re-paint and re-paint ...) an old shell or use scrap styrene for practice.