"I received an Aztec single action air brush for a gift and I've never used one before. Is this a good starting air brush? I will be attaching it to a small compressor with a 5 gallon tank, a will be buying a "Milton" brand pressure regulator w/ moisture trap. Any word of advice about this set up? I'm assuming I will be upgrading this air brush in no time, but want to get my feet wet first."
I have never used an Aztec AB, but I do own a single-action siphon-feed along with a couple of dual-actions. I find I use the single-action quite often actually. I use it for priming, spraying large areas with solid one color (such as car models), and gloss coating. Once I finally got it adjusted to my liking, that was it, never changed it since. As far as air compressors go, as long as it can supply "more" air pressure than you need it will be fine. I say "more" because you don't want the a/c to constantly be working at it's maximum capacity. For spraying models 30 psi should be more than enough. Spaying T-shirts require 60 psi. Regarding the Milton regulator - The ones I have seen or read about are of a high pressure nature, example - 0 - 150 or 0 - 250 psi. That would make it a little difficult for small pressure adjustments, say going from 20 - 25 psi. Personally I would try to get a regulator that maxed out at say 60 psi and had one psi increments. That would be a bit more accurate and easier to use for small adjustments.
"Also, what is the proper tecnique for mixing paints? How do you get accurate ratios, with an eye dropper? If eyedroppers are the way to go, do you waste alot of paint in the measuring process? I will be using acrylics, Pollyscale, Testors Model Master and Tamiya brands."
I have mixed paint for 1:1 car painting for years. There's really no need to be a drop accurate. What I do is start with a small empty paint bottle (a old Model Master enamel jar, I have a few LOL) and fill it about 1/2 full of paint. I then pour in the thinner until it's 3/4 full. Stir with a wooden toothpick and watch the drips, adjust by adding drops of paint or thinner as needed (glass eye-dropper). One thing to keep in mind, milk consistancy is pretty thin (almost watery). Once you play around with the paint consistancy, air pressure, and spraying distance from the object, you will get the hang of being close for the paint thinning. Practice on some old plastic milk jugs first.