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we sprayed some pvc letters with acrylic satin Ben Moore paint and there are very small dull spots that look like water spots. We have sprayed several times before without this problem. What could it be that's causing this? We thought maybe it was the temperature change since it went from 75 degrees when spraying and dropped to 50's overnight, but we scuffed and repainted next day at 75 degrees and the spots returned.
-------------------- Jean Shimp Shimp Sign & Design Co. Jacksonville Beach, Fl Posts: 1298 | From: Jacksonville Beach, Fl. USA | Registered: Nov 1998
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I'll take a stab at answering your question, but not being there to actually see these spots is a disadvantage.
I believe the whole thing stems from improper cleaning. If you cleaned the PVC first with LT or alcohol first, the you may have only partially cleaned them. There may have been some sort of WATER borne contamination there, that could only be cleaned off with water. I know this to be true with spraying plastic sign faces. You have to clean BOTH ways, with solvent AND with water.
I'm guessing that the flat spots are some sort of waterborne contaminent that is now under the first paint layer, and now it keeps migrating to the top, much the same way as a knot will keep bleeding through latex unless sealed first.
I dont know how many of these you are dealing with or how big they are, but you might try a coat of KILZ or similar product before you attempt another coat of the acrylic. And be sure to lightly sand or scuff between coats. Maybe try one letter first and see what it does...
Well, thats's MY take on the subject.. hope it helps......
-------------------- Jeff Ogden 8727 NE 68 Terr. Gainesville FL, 32609 Posts: 2138 | From: 8827 NE 68 Terr Gainesville Fl 32609 | Registered: Aug 2002
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