Refurbishing Tail Lenses

3005 Views 26 Replies 12 Participants Last post by ocduff, May 22, 2012

ocduff

Discussion Starter · Mar 10, 2011

2

Anyone have any experience restoring the clarity to the rear tail lamps on the S4 Series Spider? Most of them look yellowed and cloudy - my feeling is that this is not a problem with the outside of the lense, but water getting inside them (they always seem to have moisture in them). Over the years, some seem to have fared better than others. Here are pics of a clean, original Spider, and one that probable got a lot more weather exposure.

My feeling is that the lenses would need to be physically taken apart (which they were not designed to do). Anyway, a search on here was fruitless - was wondering if I'm better off leaving them yellow or spending an afternoon cutting them apart, cleaning and gluing them back together.

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maxwedge

· #2 · Mar 10, 2011

I would guess that a fair amount of that actually is UV damage which you may be able to polish off the outside with headlight restoration polish (or really any decent plastic polish) and maybe some extremely fine sandpaper 1000-2000grit. The inside is going to be bumpy and rough, but you may have some luck with the polish and a toothbrush. I took apart the lenses on my old Saab and polished the inside, doesn't look new, but much better than it did. Be very careful taking them apart, that old plastic is usually very brittle.

Gubi

· #3 · Mar 11, 2011

Yeah, I had *moderate* success polishing the outside with plastic polish to remove the outer oxidation. Start with that, or if you want to get more aggressive try the fine sandpaper (and then re-polish with coarse/fine plastic polish).

In the end I just ended up replacing mine with new. Got a surprising amount for the old ones on eBay, even with some yellowing.

IIRC it's going to be a real challenge to get them apart without damage, and even if you do you're not going to have much success polishing the inside surface due to the molded-in lenses.

Joe Papa Sr

· #4 · Mar 11, 2011

1000-2000 grit is still too coarse. Its Ok for initial, but you have to work way down to the 4000 eventually. Plastic is so unforgiving. Oh, have to do it wet.

Toothpaste with a damp rag works faily well, but lots of muscle power. I tried it!

ocduff

Discussion Starter · #5 · Mar 11, 2011

Thanks for the replies and expert insight. I've yet to try and buff the outside of the lenses. I'll try that first and see how that goes. I'll post back with the results here in a couple weeks when I get to it on my "to-do" list.

DDS

· #6 · Mar 11, 2011

I have used the polishing kit for plastic headlights covers with very good results. There are a number of products out there.

ocduff

Discussion Starter · #7 · Mar 11, 2011

Ok, so general consensus seems to be that the yellowing is mostly on the outside of the lense. I seem to believe it's on the inside (or that the plastic is yellowing inside the plastic itself). Will post back with results.

Kilgore Trout

· #8 · Mar 12, 2011

Aren't there 2 different styles of S4 tailights, one with a yellow/orange signal section, and the other with all clear? I know this because a friend bought a used one on eBay, and it didn't match what was on the other side of his car. Forget which he had and which he bought, though. Might want to check that out as a possibility, as I can't be sure from the pics. My '92 has the all clear style.

Gubi

· #9 · Mar 13, 2011

Yes, the ones in the pic above are the "white" taillights. These are what came on my '91. The replacements that are currently available are the "red" style and are what I have now.

vf31rhill

· #10 · Mar 13, 2011

Mothers products advertises a ball on a stick which you use in a slow electric drill or an electric nutdriver. They advertise this for restoring clear plastic headlamps - you use it with a liquid compound that they sell as well. During Vietnam we used a polish in a plastic bottle called Canopy Cleaner and Polish and it worked well on the plexaglass canoies of fighter jet aircraft. I am thinking that the Mothers product is a modern verison of the old canopy cleaner. You can buy Mothers products from most automotive parts stores like Advance and Autozone. This mght be worth a try.

Good Luck, Robert Hill in Memphis, TN

Tifosi

· #11 · Mar 13, 2011

Any reason the think sloshing some CLR around in there would or wouldn't help?
Its supposed to be good for that kind of thing and plastics safe.

*its not anything I ever tried or saw someone else try, it just kinda popped into my head as a 'what if' and not much more.

Gubi

· #12 · Mar 13, 2011

CLR is an acidic cleaner for dissolving hard water and rust stains. It's not at all appropriate for this sort of application.

Kilgore Trout

· #13 · Mar 13, 2011

Gubi said:
Yes, the ones in the pic above are the "white" taillights. These are what came on my '91. The replacements that are currently available are the "red" style and are what I have now.

You're right - that's what I was thinking of. Sorry for any misinformation.

Gubi

· #14 · Mar 13, 2011

Kilgore Trout said:
You're right - that's what I was thinking of. Sorry for any misinformation.

Well, no, you were right about the differences. I don't think there's any standard naming, that's just what I've called them in the past

Anyway, I had people try to tell me that there was only one style and mine were just oxidized so they looked white, but that's definitely not the case: there were two designs over the S4 build.

lgbalfa

· #15 · Mar 13, 2011

What you could do is just swap them from the red car to the black.

Nick S

· #16 · Mar 18, 2011

Plastic polish

ocduff said:
Anyone have any experience restoring the clarity to the rear tail lamps on the S4 Series Spider? Most of them look yellowed and cloudy - my feeling is that this is not a problem with the outside of the lense, but water getting inside them (they always seem to have moisture in them). Over the years, some seem to have fared better than others. Here are pics of a clean, original Spider, and one that probable got a lot more weather exposure.

My feeling is that the lenses would need to be physically taken apart (which they were not designed to do). Anyway, a search on here was fruitless - was wondering if I'm better off leaving them yellow or spending an afternoon cutting them apart, cleaning and gluing them back together.

I found that metal silver polish works really well to get the haze or cloud off the outer part of the lens with very little effort.

Nick

ocduff

Discussion Starter · #17 · Mar 18, 2011

Ok, at first I just used some plastic polish, and when that didn't seem aggressive enough, I hit the lense with 1500 grit wet sand, theb 2000 wet, then Light Polishing compound with the orbital, then an even lighter grade, then a cleaner wax, and then a final coat of a glossy wax. Will post pics tomorrow when the car is back together and I'll let you all see if it made a difference.

ocduff

Discussion Starter · #18 · Mar 25, 2011

2

Update: Finally posting some pics. Before and after. What do you guys think?

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Gubi

· #19 · Mar 25, 2011

Looks like you did a nice job. Spray them once in a while with some 303 Aerospace Protectant: it'll keep them from getting UV damaged in the future.

aldo

· #20 · Mar 25, 2011

Convertable Top plastic looks better too. Did you do that.

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