How do you thin Acrylic paint so that it can be used in an airbrush

As I gained experience with using airbrush paint, I have come to the conclusion that using Vallejo model air paint with their thinner works well for me. It isn't all their colors, after all it is considered as airbrush paint, but I did find that black needed thinner. I have no idea why but it does. There may be other colors, but I don't know.
Yes, I find there's variation in the amount of thinner needed too and of course as the amount in the bottle decreases, from use, and gets a little thicker I’ll add another drop of thinner in the cup. Most times I’m ok at the 10:1 ratio and sometimes none at all. If I keep getting dry tip I’ll take note and add a drop of flow improver as well. I find the white primer and the yellows a pain to use but the grey primer is great.
Kevin, here's my issue with airbrushing acrylics. First, I built my first model plastic airplane in 1956, been modeling a long time. Got my first airbrush in the 70's. I own several different airbrushes and use a 3-gal pancake compressor from Harbor freight. My airbrush of choice for model ship building is a Badger 150, medium tip. Use very low air pressure.

I have had no problem with applying acrylic paints with a brush. But, when airbrushing, clogging and cleanup has been an issue. That's not to say I haven't had success, but it's been frustrating and, in my opinion, not worth the effort. Consequently, I will only airbrush using enamel or lacquer-based paints. Acrylic paint seems to clog the inside of the airbrush, not just the nozzle. With solvent based paints, cleanup is easier. Also, I find it is more difficult to get the right consistency and regulate flow with acrylics.

One downside, the color offerings with solvent based paints versus acrylic paints has become limited. Hence, if you buy basic colors and a small color wheel you can match most colors.

The photo below is my current project. Airbrushed the bulwarks a few days ago (enamel paint). My point with the photo is the lack of paint overspray, no spitting or running. I test start with the lowest air pressure and adjust until it's a smooth even flow. When I built the Dory I was going to use Manufacturer recommended acrylic paint but decided to just mix my own batch of enamel.

Again, this is just my experience, lots of trial and error.



I use Tamiya acrylics for my airbrushing and thin the paint with Tamiya lacquer thinner. I fill a new mini up to the second ring on the bottle using a Tamiya airbrush at 15psi. the results are great I used this formula on my 1/8 scale formula car body with excellent results,I applied 3 coats 2 light coats, and one heavy third. airbrushing for me was practice, practice, practice. but the above formula works very well, the lacquer thinner gives the acrylic holding property helps with the run problems with acrylics