Saving thinned paint

It depends on how long you want to store the thinned (reduced) paint, and what you used as a reducer. A few days to a week, at most, is probably okay. However, some paints are less tolerant, and may go off in a day, especially if you use a marginally compatible reducer.

Since you just got the airbrush, you can use the extra paint for practice on a paint hulk or scrap plastic. Some recommend an old milk jug or similar container as a practice target. If you think you like the airbrush now, just wait until you've practiced enough to be really skillful.

I have that thinned enamels have a tendency to spoil rather quickly.  What seems to happen is that the pigment congeals into a blob at the bottom of the paint bottle and no amount of stirring or remixing seems to help.  On the other hand, I have had great luck preserving thinhed acrylics.  As with enamels the paint and thinner separate, but unlike enamels, I can usually stir the paint and thinner, and spray successfully.

I save thinned Tamiya acrylic all the time with no <knocks wood> problems.

So far! Now that I've mentioned it, I'm sure something will happen!

I just used the last of a thinned Tamiya cockpit green/flat white mix that has been sitting in a mix bottle for about 4 weeks. No problem, just gave it a good shake. Don't know if it makes a difference or not, but I use Tamiya's acrylic thinner exclusively.

-dave

 

Enamel thinners might contain additives such as terebene to help the paint dry. That might cause the thinned paint to set if it's stored. Terebene is very useful if you have problems with enamel paint drying slowly or slightly sticky. Artists use it with oil paints - called siccative.

I will save thinned A/B paint only for the time I am building the model (not long)...... for possible very small hand brush touch ups. Man paint can get expensive. I bet I will spend $40 bucks on paint for the Revell ISS I'm buildiing right now, and the B-36 I've given a rest on for now ...around $60.  I don't blame anyone for trying to save.........although I just went through my paint storage and through out about 15 old bottles of MM. and around 7 bottles of Tamiya.

MM enamel will gum up within a couple of weeks from my experience.