I waited a minimum of 90 minutes between coats. I put five coats on the barrel & receiver and the other parts which I sprayed in that batch, and the fifth coat left me irate. I had thought I was ticked off during the fourth coat, but I was wrong. The constantly-clogging airbrush, which had been thoroughly cleaned between each coat, led to uneven application and a slightly "chunky" finish.
Don't get me wrong - Perma Fin is supposed to provide a slightly textured matte finish. But a uniform finish would be nice, and the airbrush problems I experienced prevented me from fully achieving that.
The small chunks I mentioned on the previous page left a finish that's not quite as smooth as I'd like it to be. On one hand, the increased texture of the finish allows it to better hide flaws in the gun's surface, but on the other hand, the smoother finish was looking a lot better to me before the clogging problem arose.
Overall, though, I'm pleased with the results of this project, and my ire was soothed as I admired the finished parts and began to assemble them.

