I have a 1990 Formula. The center filler piece to my tail lights was looking bad, so I decided to re-finish it. I removed all of the paint from the inside. I polished the plastic so that now it looks like pane glass! I had a decal made to replace the original bird. I am at the point now where I am ready to re-paint the inside of the panel. What do I need to do to prepare the plastic for paint? I'm afraid to clean the surface with thinner for fear of discoloring it. I'm afraid to use any type of paint adhesion promoters because they might not dry crystal clear. Should I just spay the paint directly to the plastic? Will any of the compounds that I used to polish the plastic prevent good paint adhesion? Any help is greatly appreciated!

 

The polished surface will make it impossible for paint to stick, especially if the polish had any sort of wax in it.

You need to clean that off to begin with. Paint thinner may be a tad harsh, so stick with something like Alcohol or a good degreaser like "Greased Lightning Orange Blast". That stuff seems to work well.

Anyway, once it's cleaned off, it might look a bit dull, but that's ok. Take some 10 micron (or 2000 grit) sand paper and lightly (and evenly) sand the surface. When you're done, you should have smooth feeling, but cloudy surface. This will give the paint something to adhere to, but the marks are small enough that the paint will completely fill them in and from the front you'll have a perfectly smooth, glossy finish.

 

OK. Thanks Jim85IROC for the info.

But ..... there is a problem with that plan. After I scuff the surface with the 2000 grit, the decal has to go on before the color. So, should I shoot it with clear gloss enamel before I apply the decal? Then shoot over everything with the color?

 

That should work. Just don't wait too long between doing the clear and the color. If you do it while the clear is still fresh, the color should still bite into it and adhere well.