View Frost Issues With Spray Varnish
Many figure painters have reported ruining figures when the clear spray varnish they were using left a chalky white or cloudy coat on the figures. The problem, while thankfully rare, has occurred with enough frequency that a wide variety of solutions have been developed.
Painters have had verying degrees of success with each of the following solutions. The first three, however, seem to have been most effective.
1) Respray the figure with a different can of the same varnish. Some users have reported that the new layer “melts” the old and clears up the problem.
2) Using a brush-on varnish, such as Humbrol’s or Testors, recoat the figures. Again, it’s been reported that the new layer “melts” the old.
3) Using a cotton swab, wipe down the figures with mineral spirits (this is also known as “white spirits"). Do not apply too heavily, and let the spirits evaporate completely before reapplication.
4) Use a soft brush to brush off the white coating.
5) Soak the figure in a slow-acting paint stripper.
5) Heat the figure in an oven at a low temperature.
There doesn’t seem to be any definitive cause of the problem. Painters have reported having trouble with several brands (must usually Games Workshops Citadel product), but it seems that someone has had a bad experience with virtually EVERY brand.
One suggestion is that the problem occurs when the humidity is too high and water vapor gets trapped in the varnish spray. Its plausible, but if that were the only reason, then no one would be able to spray varnish a figure in Florida. Most likely, it’s the result of a bad confluence of factors.
Here are some suggestions that have been offered to avoid “frosting” in the future:
1) Test spray an unwanted figure first just to be sure that the can is working ok.
2) Spay only on warm, low humidity days.
3) Before spraying be sure to shake vigorously, for a long time.
4) Before spraying, warm the can in a shallow pan of warm tap water. The water should not be any hotter than you can keep your hand in.
5) Store the can in a place where it is not subject to the vagries of temperature. i.e. inside the house. Extreme changes in temperature may be responsible for bad cans.
6) A majority of people seem to agree that Krylon or another of the commercial brands are of a higher quality and less subject to the problem.
6) Give up on spray varnish and use the brush-on kind.