Restoring Plastic Inner Fenders

[GrayCav56]

My newly acquired 66 Pontac GTO has the rare red plastic inner fender liners. While they are all in pretty good shape, they are obviosly far from "First Junior" level. They have a few screw holes where previous owners attached mudflaps and have some wear and tear you'd expect over the years.

Does anybody have any experience restoring these? I'm thinking that using some very fine grade sandpaper should smooth out some of the scratches, but I'm not sure how to fill in the holes and blend them to match the impregnated color of the rest of the plastic.

[Guest bkazmer]

I'm not sure what these are made of, but I suspect ABS or PP. If ABS, this gets easier - gel coat repair for boats should stick, as "royalite" canoes are ABS. If PP, much more difficult to adhere, but body shops sell a two part formulated for repairing TPO bumpers, then paint. Quick way to try and tell - give it a tap with your finger. ABS and polystyrene have a ring (like a plastic model), PP sounds dead.

ABS = acrylonitrile butadiene styrene

PP = polypropylene

TPO = thermoplastic polyolefin

[GrayCav56]

Thanks bkazmer. They are a softer, dead sound, so I suppose PP it is.

[Guest sccars49]

The panel should be coded with the id of the type of plastic as noted above. There are many different plastics used now but only a few back then. You can add polyurethane & polyethylene to the above list. Most likely it is Polypropalene or Polyethelene. I have a plastic welder(basically a solder iron with a temp control) from Urethane Supply Co. I don't have my old lit handy with all the codes but you probably can find out more on the web. Most, if not all, non catalyst plastics can be "welded".