Originally Posted by RBean

I have an old Brinks air brush for small detailed work, such as the green mottling and exhaust stains etc. For the bigger areas I use a Badger model 400-2 touch up gun. The paint is fuel proof, but I have found the oil and gasoline will discolor the paint. The coating of clear lacquer prevents this. I lightly sand to arf finish with fine sand paper or steel wool, then use grey auto primer. For planes with a grey under side I just leave the primer.

I use a brush for small touch ups and to cover small hanger rash. I have been told there is an additive you can mix with latex that will prevent brush marks when you use a brush, but I have never used it an can't remember the name.

Harbor Freight sells a chinese copy of the Badger touch up gun for a relatively low price.

The good part of the latex is it is cheap, you can get in small samples, it cleans up with water, does not stink up the house and is not flammable.

Because latex, thinned enough to spray, can run, it is best to use two very light coats. I use a heat gun to speed drying and help prevent runs.

Here are some other planes painted with latex.