Go to method to restoring plastic

[Fourwheelhorse]

What is your method to restoring some fairly weathered plastic? I recently purchased a fender off of fleabay, it was described “ ok” but did leave out that the fender was weathers and has some pretty good sized scratches in it. I’ve heard/ seen in the past that one can wet sand and buff the fender to bring it back, I’ve also read about the use of heat guns. Just curious as to what you guys prefer. Also I can’t seem to post pictures on here, or else I would do a before and after pic.

[ATC King]

Elbow grease and patience.

Don't use a heat gun except for finishing. If there's any weathered plastic on the surface and heat is used, it'll just embed itself in the good plastic underneath and be nearly impossible to remove. All the damaged/weathered plastic needs removed first, then a heat gun can be used to put a final finish on it, bring some color back.

Basically, the worst of it will be best physically removed. Razor blade, a progression of sanding paper, and other methods that are slow enough to keep an eye on the work without taking too much off at once.

The more labor, the better they'll look when done. Trying to go fast and use some product at the end to cover what's left won't hold up. There aren't really any shortcuts if it's to hold up to close scrutiny.

[knappyfeet]

Kings right.......there's no secret magic trick. It's monumentally time consuming.

I think the hardest part is going through all the sanding stages...that takes forever. All the faded, oxidized plastic needs to be scraped off with a razor, along with scratches, etc. If you take your time and be careful with the razoring you can reduce the sanding time considerably. Plus it's very rewarding to scrape off the old and reveal the new.



Don't use the heat gun unless you need to. On lighter colors you can brown it sometimes before it flash melts. Buffing should suffice.

Good luck

[Footy]

What about removing spray paint?
I have seen videos that recommend using Aircraft paint stripper for removing paint from plastic.

[ATC King]

At a factory I worked, we used heat guns to 'repair' minor blemishes in new plastic parts.

At the end of each assembly line was at least one repair station and heat guns got plenty of use, especially when a batch of plastic parts we received weren't handled with care or the place that made them let some machine issues slip by before recognizing. Plastic injection molding machines can get temperamental and pump out quite a few questionable parts before someone notices.

[ATC King]

What about removing spray paint?
I have seen videos that recommend using Aircraft paint stripper for removing paint from plastic.

That's a different issue, and about a coating. Like anything, do a test in a small area before proceeding. If you really wanted to test something and save money, you could try brake fluid. I'm not suggesting anyone runs out and tries it without due diligence, just saying that it could work, and cost less than any paint stripper. That's one reason some vehicles us silicone based brake fluid, so it won't ruin the paint if spilled. DOT 3,4, 5.1 all should take paint off, but DOT5 is silicone and won't.

My question would be why they painted them and if it was a quick job on nasty plastic or they done it right and just for a color change. I've painted several fenders, and most of them was because they looked bad, or were too rough to restore. Anyone removing the paint from those is going to find a lot more scratches than they thought. It's not like they can just remove the paint and polish the plastic, hence the reason why I painted them to start with.