samourai47

I've been airbrushing for about a year now so still pretty new. Hope this helps 1. You should have a watertrap on the compressor, if so then as long as its not coming through the hose into the brush then it's fine. Just empty the trap every so often 2. Ratios with vallejo paints are all up for interpretation, personally I've been using a .4 needle with vallejo air paints, it sprays neat at 20psi but I tend to thin it down slightly 1:4 thinner to paint. Don't pre-mix the paint, apparently it can go funky so best to just mix before you spray. I used flow improver in the past but found it didn't go much for me. 3. Same as above really, depends on scale, and what you're doing. I have a cheap brush with a 0.5 set that I use for priming and then a different brush with 0.4 for everything else. If I needed to do detail then I can switch to 0. 2. 4. I prime exterior but not interior, I find if you don't prime then the paint doesn't stick as nicely and can cause the issues as you've mentioned I would avoid the Vallejo primer and get some MIG oneshot if you're sticking to water based Arcylics like me. The Vallejo doesn't sand well and I've found has rubbed off at times. 5. As long as the compressor works I don't think it's worth it to change, possibly the airbrush if you're comfortable. I practiced for a few months on a generic brush from Bartsharp before getting a H&s evo