Okay—I had something funky happen last night while I was spraypainting a component of my Halloween costume. Would love to know if it was some type of chemical reaction or what…
Object being spraypainted: a plastic crown. The plastic came from an old lampshade that I dissected—very sturdy, had to cut it apart.
Spraypaint: gold Krylon (the shiny metallic kind).
Event: When I checked on its “drying status” about 10 minutes after I painted it, I noticed one of the spikes was floppy. I picked it up and played with it a little bit, only to discover that the whole crown had developed the consistency of wet newspaper!!!
What the heck happened here?!? It was very stiff plastic—did the spraypaint loosen its bonds or something? And how come you can spraypaint cardboard and this doesn’t happen?
I was building a model car as a kid. I got some of the paint on the windshield of the car. I decide to soak the windshield in some paint thinner to dissolve the paint. I came back several minutes later to find the entire windshield completely missing. Took me a minute to figure out what had happened. The entire windshield had completely dissolved in the paint thinner. But, hey, it was clean wasn’t it? <G>
Paint is kept liquid by being dissolved in thinner, many plastics dissolve just as easily (if not more so). When spray painting over plastic, use many very light coats of paint to minimize the problem.