Painting plastic for the first time

Todd Gatman

Promoted Users
Hi all,

My buddy asked me if I would paint his plastic race car bumper. It has been modified and lightly sanded before I got it. I was planning on shooting a reduced coat of epoxy on it and them proceeding with base and clear.

When I got the bumper, the condition is per the photo below. It looks like there is a factory coating that has been partially sanded through. The coating is rough and looks like it should come off before painting because there is no doubt in my mind you will see this. If I do wetsand it off, does adhesion promoter before epoxy become the right procedure?


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Trying to be the best me, I can be
First get a glass of water and take a small sliver of the bumper off and place it in the water. If it floats it needs adhesion promoter. If it doesn't float then you don't need to apply ad-pro. Chances are though that it will.

Get every trace of old material off. Follow the instructions in the SPI Tech Manual for prep and application. Then follow up with the epoxy as your sealer.


Trying to be the best me, I can be
I should add that more than likely you will need to prime before sealing it and painting. Use the epoxy (SPI) for your primer. Just apply the ad-pro first per the instructions in the Tech Manual. If you need to apply any glaze do it over the epoxy. If you sand through any where re-apply the Ad-Pro before applying more primer or sealer.

Keep asking questions if you have them.:)