I've been using a water-based approach to refinishing plates for the past 3 years or so with good results. I use a high volume low pressure (HVLP) turbine for spraying, but compressed air should work just as well, although the technique will be slightly different. The plate must be out of the piano. Spraying solvent based lacquer is a little easier and quicker than this approach, but not having to deal with the toxic fumes is worth it to me. 1. Rinse and clean the plate with WATER. I use scotch-brite pads and put water in my turbine and kind of spray and clean as I go. I then "blow" dry and let the plate dry. 2. Wet sand, grind or whatever to smooth the surface. End this step by thoroughly cleaning with a lint free damp cloth to remove dust. Again using only water. 3. Primer coat. Because the only water-based gold tint I could find is a "Pearl Luster", which is semi-transparent, this step is very important. The gold color you wind up with depends both on the color of the primer and the consistancy and thickness of the gold topcoat. Basically, as the primer color moves towards black the topcoat moves towards green; as the primer moves to white the topcoat moves to orange. I use a grey primer which I mix myself from white & black primers. I adjust the gun (HVLP) to spray as fine as possible without clogging and make several passes. This coat should be dry enough to dry sand in about 1 hour or less, for wet sanding I would wait overnight. I generally wait overnight before spraying the gold. 4. (optional) Dry sand & fill as needed. If the plate looks good at this point you may only need to wipe clean and sand a few areas. I sometimes need to fill in small areas with "spot glazing putty" (solvent based is fine). Apply a light second coat of primer if desired. 5. Gold Topcoat. I gently stir into 1 pint of clear water-based finish 2 to 3 tablespoons of gold pearl luster powder and let sit about 10 minutes. The finish is such that if you shake or create bubbles they take a long time to dissapate. If you spray with bubbles they WILL wind up on the surface. Again I adjust the gun to spray a fine mist and carefully go over the plate with serveral passes. Because the gold is semi-transparent, care must be taken to create an even colored coat. It will start out looking greenish. As you add more finish, more and more gold will emerge. Spray only as much finish as you need to achieve the desired color. In any case no more than 3 passes should be needed. 6. (optional) Clear topcoat. If you want more depth in the finish, spray one clear topcoat, applied as you would normally, but on the lighter side. I'll get all the company names and phone numbers together and send them in a future letter for those interested. Bill Springer, RPT
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