Repainting the plastic headlight covers?
 

I previously painted my headlight covers... it didn't last long. It basically all pealed off. I think even the stock paint had come off before I painted them.

What should I do when prepping them to be painted again so that it sticks?

Should I remove all the paint across the whole cover, or just go ahead and primer/putty them? I get the feeling that simply sanding down the edges of the paint that is left will not prevent it from peeling off again.

My JB weld repair of the cover's brackets has held up surprisingly well, all considered.

I would probably just buy new covers and paint them. Going through all the work on old covers that are on the way to failure doesn't seem like a good idea.

You can sand down, prime, and paint but if a month later it flies off on the highway that's all for naught.

New covers come pre-primed, they just need a scuff with a scotchbrite pad and a degreasing and they are ready.

You'll never get perfect results from a rattle can, you need either real 2-part automotive paint in a gun or if you have a paint shop that can mix paint into a 2-part spray can that works too.

Dale

I've put quite a few track miles on these repaired covers.

Also, new covers are expensive and I don't need perfect paint since this is a track car. The covers are the least of my worries. I just don't like the FRP/plastic showing.

New covers aren't too bad ($80 each?) but I hear where you're coming from.

Sand them until they are smooth, start with whatever grit needed to get any paint lines/scratches/etc. smooth. Work up to 220 grit, then use a filler primer to fill all the small scratches. Hit that with 320 and 600 to get a satin smooth finish, then put whatever top coat to color match. If you are doing clear over it, probably want to put a few coats of color down, go over with 600, then clear.

It's a slow process, mainly doing the work, painting, wait for paint to dry, sand, paint, wait to dry, etc.

Dale

I've had good results repainting my originals.

1. Epoxy to reinforce the mount ears where they attach to the cover.
2. White plastic paint on underside
3. Wetsand, Prime, wetsand, prime, wetsand, base, base, wetsand, clear, clear, wetsand, polish (or something like that)

Used automotivetouchup.com base coat and clear. Their 3L is a really good match for the Mazda 3L SSM.

It's a mechanical bond, if the paint peels off it's an issue with the prep. Get a grey scotch pad and go over the covers until all the shine is gone. Providing you don't go through the paint you can base and clear on top of that. Be sure to use tar, wax and grease remover (Panel wipe) before shooting any paint to ensure it's all nice and clean.

Is your FD silver? You should never sand or even wet sand a metallic base. Just clear strait on top and wet sand that instead.

:icon_tup:

Sanding metallic paint will change it's reflective properties. Also, get that clear coat on ASAP.

There's absolutely positively no way I'm going to be able to get surface flat without using a power tool.

180 grit sandpaper is not going to cut it.

Should I just putty this thing first?

Found some 100-grit sand mesh.... things....

Took some elbow grease but I think I finally got it flat enough to prime. I hope the primer will take the scratches and other imperfections out.

I'm probably gonna have to completely redo the other cover with some 80-grit mesh.

Yes.

And one should never interpret painting word salad typed by a person who has covered an entire E28 race car in synthetic fur as proper instructions.

I'm gonna have to go buy some spot/glazing putty (couldn't find it at Autobacs) since the primer didn't quite take scratches and pock marks out of the surface of the one I actually managed to sand flat.

Anyone have a suggestion for how to quickly remove all the paint from the surface of the other cover? A wire brush on a drill is too harsh on the cover itself. My angle grinder and Drimel tool are out of the question....

Are you doing multiple coats of primer and wet sanding?

I was able to get some pretty bad dog bite marks out of a pair of mud guards. Just used rustoleum grey auto primer, I'm sure you could find equivalent. Lay it on thick and 600/800 grit. Wash, rinse, repeat.

Post up some pics of those battered old slabs. Sounds like they've been sent to hell and back and I wanna see!

80 grit is probably as low as you want to go. If you can use a DA that will make it go pretty fast. I wouldn't use a chemical stripper or anything that could potentially eat the plastic.

You're seeing why I recommended new covers :).

I just looked, part number

FDY2-51-SH2

is $78.75 from Amayama, that's the driver's side cover.

Dale

I took enough of it off with 45 grit paper that it finally feels smooth (after some 80 and 320 grit sanding), although I suspect the feathered edges might still peel off at some point.

I wonder if I should keep trying to remove the rest of the paint, or just go ahead and try priming/surfacing it.

I would just about rather spend $40 on spray paint and sandpaper than $200 (the price here) + $100 for professional paint... lol

It only needs to not peel. I don't care if it doesn't look perfect.

I finally got around to buying new covers. Hahaha. They were more like $110 each at this point.
The paint had all came off again, despite the many hours of sanding and priming...
I am debating whether I should get them painted professionally or now, since it'll probably cost as much as the covers did and take weeks.
I think the reason the paint wouldn't stick was because they covers had lost any semblance of rigidity, so they would flex more than the paint was able to handle.
It'll probably stick this time, but it won't look quite as good as professional painting. Unless the paint does need to be flexible...

Originally it probably had nothing to do with reusing the covers.
Headlight covers, just like bumper covers require an adhesion promoter. Without it neither paint or filler will stick to the plastic. They both require a flex additive as well. It can be a little tricky to use to latter and get good results. I’ve been away from that type of work long enough to know my limitations, and just have a good shop do it these days.

Ah… well, good, since it turns out professional painting won’t actually cost that much.