Too much alcohol can gum up the brush and make the paint dry too fast (some people get away with it), but a little can promote the flow of the paint and cut surface tension and prevent beading. I use a mix of 80% water and 20% alcohol and keep it in a Polyscale or Model Master thinner bottle.
Jay
C-415 Build: https://imageshack.com/a/tShC/1
Other builds: https://imageshack.com/my/albums
I agree with Jay. mostly.
You don't want the paint to dry too fast, especially not inside the airbrush. I cut the 70% alcohol by 50% with filtered water (although distilled works, too, it's just more expensive) and use that.
But really, there's no "best". If you've always used distilled water, and you're happy with your results, then why change?
Connecticut Valley Railroad A Branch of the New York, New Haven, and Hartford
"If you think you can do a thing or think you can't do a thing, you're right." -- Henry Ford
I've always used plain old tap water to thin acrylic for airbrushing, and it's never given me a problem. At this point I prefer enamel for airbrushing.
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Neither. Liquitex Acrylic Airbrush Medium is the proper diluent to use for acrylic paints. It is the base they are made with, and is the equivalent of the proper paint thinner that you would use for a solvent based paint.
Greg
I've been using distilled water to thin Polly Scale acrylic paints for several years, and I'm very happy with the results. I thin about 10 percent (by eye) according to the manufaturer's instructions, and I add 6 to 8 drops of Liquitex Acrylic Flow Aid per ounce of diluted paint. After painting I spray Badger Airbrush Cleaner through the airbrush, but I clean siphon caps and in-bottle strainers with tap water.
I don't understand why Cody or anyone else uses alcohol – you'll have to ask them.
So long,
Andy
Andy Sperandeo MODEL RAILROADER Magazine
When I first tried airbrushing with acrylics, I used alcohol as a thinner, with terrible results: irregular coverage and constant clogging of the tip, and very difficult to get even a single boxcar painted. I decided to stick with lacquer-based paints, with which I'd had good results for over 30 years.
I later tried acrylics again (due to complaints about lacquer odour, even though I use a spray booth vented to the outdoors) but this time took the time to read Testors' suggestions for airbrushing PollyScale. While they, of course, suggest their own thinner, distilled water was an alternative. They also recommended a lower pressure that I had seen mentioned on various forums. These two changes made all the difference, and I was able to paint, in one session, four dozen freight cars without a single incidence of clogging. While I still prefer lacquer-based paints (clean-up is much easier), acrylics are now well-represented in my paint cupboard. I solved the odour issue by moving the paint shop to the garage, about 100' behind the house. This also makes it easier to paint in the middle of the night without complaints about the noise of the compressor.
Wayne