I am spraying testor's dull-cote laquer through my airbrush before I begin weathering. I've noticed a white "frost" building up on some of the model surfaces. Is this a chemical reaction to the glue I'm using or what?

Hi,
this has been previously addressed in another post. The most probable reason is a too thick coat of lacquer.
Try to thin it a little bit more and spray several thin coats instead of a "heavy" one. It should solve your problem. I experienced it some times when I started this method.

olivier

Also could be that you are spraying too far from the surface and it is drying before it reaches the model. And as also stated, the coat could be too thick as well. HTH "Q"

It may get better (clear up) as it cures. I have had this happen using Dull Cote out of a rattle can. I freaked but it cleared up.

Shaun