Hi Bob, The lifting is caused by trying to spray too thick a coat with too fast thinner. What happens is that the surface of the coat cures too quickly for the thinner vapor to air out of the entire coating thickness. This results in a bubble being formed where the coating is the thickest - in the corner. The solution is to spray thinner coats and/or use a slower thinner. On material, I have tried acrylic lacquers from auto supply stores and was very unhappy with the results. I have been told that acrylic lacquers are very brittle, which my experience has supported. Also, automotive paints have a great deal of pigment mixed in with the bronzing powder, which the factory finishes don't. To me, a plate finished with car paint looks like a car, not a piano plate. I went back to plain nitro lacquer with bronze powder. I used solid body nitro primer at one point, but eventually decided it was just adding to the coating thickness without contributing anything to the quality. Now I just use nitro lacquer sanding sealer with (lacquer) spot putty to fill the chips with a color coat of 50/50 clear top coat and sanding sealer and bronzing powder and a clear coat of the same on top. BTW, once thoroughly cleaned and sanded, the old shellac bronze coating makes a fine undercoat for the nitro lacquer... I wouldn't be so sure about acrylic. Mark Story, RPT Eastern Washington University mstory@ewu.edu > Could some of you rebuilders throw out some of your techniques for > sealing the > old plate finish before applying bronzing lacquer? I hate the thought of > stripping the old finish off. In the past I've tried shellac, auto sealers > and primers and always seem to get a little lifting in those sharp bends > around the struts.
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