New to airbrushing: thinning paint

[Chris1274]

Hi everyone,

I finally got around to buying an airbrush (nothing fancy) and grabbed a working compressor off evilBay, so I'm ready to start airbrushing. However, I'm at my wits end when it comes to figuring out how best to thin the paint. I've looked at I don't know how many different youtube tutorials and have gotten a different method each time. So, how do you guys thin your paints? Thanks.

-Chris

[peteski]

That is because there is no single all-encompassing formula. Every type of paint is different and then every modeler uses their own techniques (like the air pressure and how wide to open the nozzle).  There are hundreds of different possibilities.

I don't even really keep tabs on my paint-to-thinner ratios. I just put thinner in the paint until it feels right. I guess that general rule would be for painting using solid paint (not for shading or weathering), to make the paint the consistency of skim milk. But that is also open for interpretation.  For air pressure I usually use 12-15psi (which is lower than what most modelers use).  I use Badger 200: Single-action, internal-mix airbrush.

This is one of the aspects of airbrushing you'll need to learn for yourself.  I often practice (do test painting before actually painting the model) on cheap plastic spoons.  That way I don't ruin the model and I can recycle them when I'm done.

What kind of airbrush did you get? Internal or external mix? Brand name?

[Chris1274]

What kind of airbrush did you get? Internal or external mix? Brand name?

It's a Badger 350F-9 external mix.

[Scottl]

Practice and experiment is very good advice.  My first tries with the air brush were not great, but I found I could get the feel for the amount of thinner to add pretty quickly.  I agree with Peteski, it depends on the brand of paint, the air brush and the air pressure.  Lower pressure has worked better for me, usually around 20 psi or less.

[Chris1274]

I understand that getting the mix right requires trial and error, but what I found confusing was the variety of thinners being used. Some guys use windex, others use windshield wiper fluid, matte medium, polyeurethane, and on and on. So is just plain old paint thinner good enough?

[Scottl]

Thinner is paint dependent.  I have only used acrylics and use either distilled water or Tamiya thinner.  I know you can use others like windshield washer fluid, but I don't want the other compounds in the washer in my paint.  I won't cheap out on thinner on a model I have put a lot of time into.

For solvent based paints, I'll leave others with experience to provide suggestions.

[C855B]

Thinners are indeed dependent on the type of paint, and brand. The folks who use windshield washer fluid are doing so because they find that the small amount of alcohol it contains helps with the brand of acrylic they are using. But matte medium? Polyurethane??? There's much context needed to explain those.

Bottom line? Since you're just starting out, use the paint manufacturer's recommended reducer. Period. Even if it's expensive and the forum "experts" tell you "it's just water with a little alcohol." Ignore them. When you get more experience and know what to expect, then maybe start playing around with "stuff under the kitchen sink" to modify the characteristics or reduce the costs.

[peteski]

I avoid spraying water-based acrylic paints through the airbrush. Call me "old school", but I like the stinky smelling paints. 
Having said that, I find it amusing that people try all sorts of liquids as thinners for water-based paints.  Windshield-washer fluid? Why?!  To save couple of dollars? To outdo others when it comes to finding the most esoteric paint thinner? 

I would say (especially in the beginning), stick with the thinners made for, or recommended for the paint brands that you use.  Even within all the water-based acrylic hobby paints, there is a wide range of chemistry used. A thinner that works with one brand might curdle another brand of paint.  Also do not mix different brands of paint.
 

[Kisatchie]

...Also do not mix different brands of paint.

Man oh man, tell me about it! I wound up getting a different airbrush for each brand of paint I used, and different eyedroppers too. I got tired of jellied jars of paints from the slightest of contact between brands.


Hmm... I like jelly
doughnuts...

[peteski]

Man oh man, tell me about it! I wound up getting a different airbrush for each brand of paint I used, and different eyedroppers too. I got tired of jellied jars of paints from the slightest of contact between brands.
Hmm... I like jelly
doughnuts...

The "old school" organic solvent-based paints are much more forgiving as far as this kind of contamination goes.