I use mostly solvent based paint - Floquil has a large selection of Model Railroad colors and Scalecoat is another brand of solvent based. As with any airbrushing, but especially true with solvent based paints - you need to have good ventilation. The fumes are heavy and toxic, so I also use a respirator and goggles and I wear latex gloves.
I use solvent based paints because I think the color is more true and coats better. It does take slightly longer to dry, but the finish is excellent. I also recommend priming before you paint. This has two purposes. First, I have seen paint attack plastic and decals - if it is primed, then it places a barrier between the plastic and the actual paint. Second - the primer coat will give you a very nice clean base to paint on and yield a more true color. I use Floquil Primer mixed 70 % primer to 30% thinner and about 15-18 psi if you are using a compressor - which I would also recommend if you aren't using already.
You have to use thinner to clean up Floquil or Scalecoat and other solvent paints versus soap and water with acrylics. I have found as well that acrylics are more prone to clogging your airbrush because they dry faster. This can be a real mess to clean out your airbrush. With the drying time on solvent based longer, you can clean your airbrush by simply running thinner through it.
I have used both and like all things, each has pros and cons. The good thing is that Testors makes both Floquil and Polly Scale and are readily available in most Hobby shops. Good Luck
HO Junction Custom Models
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