I experimented this weekend, after trying to use Bondo on some ABS wheel pants which failed miserably. After roughing the surface thoroughly, I still had a hard time getting Bondo to stick to the surface of the ABS parts. It sticks great to metal, as it was made for, but not to plastic.

I needed something better. Spackle is no good, as these plastic parts flex a little, and spackle easily cracks. So, I tried a product made by DAP. Used it for making cabinets before.

It is called "Plastic Wood", made by DAP. And it works GREAT!!! Especially for plastic parts. I used it sparingly, as it is heavy like Bondo. But it really sticks well, and is more flexible than spackle. After letting it dry for several hours, I sanded this stuff so smooth that it blended right in, and was much nicer than the Bondo. It takes primer and paint with no problem. I am going to use this from now on. It is so much easier to work with compared to Bondo, and doesn't STINK either.
I bet this stuff would work beautifully on fiberglass parts as well, it just seems to stick to everything.

Patriot

FlyBoy Dave - I'll give that a try next time. Always looking for a better way.

I've used glazing putty and epoxy with microballoons. Both work ok, but the glazing putty can crack after a while depending on how thick it had to be to fill the seam. Glassing the inside of the seam helps a lot.

- Paul

Epoxy always seems like the best way to go, especially for a glass cowl etc. But this stuff sure is easier to sand. Knocked it down with some 100 grit, then finished off with 220 and 400. So far so good. Only time will tell.

Patriot