Renewing yellowed headlights

A while ago there were a few discussions about restoring older plastic headlight lenses. I have a hard time finding them, so I post this question again: Does anybody had success restoring older headlights? What did work? Rubbing compound, fine sandpaper or toothpaste? How would you do it? Any advice appreciated.
Thanks!

If you don’t want to buy the kit made by Mothers there are youtube video’s on the subject. Toothpaste only would work for lightly yellowed lenses but fine sandpaper and water seemed to help quite a bit. http://www.youtube.com/watch?v=mD0HLQn2coE Fair warning his language is a little strong for the first minute or so.

I’ve used 1000 grit wet/dry sandpaper followed by 2000 grit wet/dry with water followed by polish. However, it never seems to last. Six months, a year, etc and it becomes a redeux.

Do NOT buy the Sylvania kit

It’s overrated and doesn’t work, at least not in my experience

I bought it, followed the instructions TO THE T, and a few months later, the headlamps were yellow again. Not only that, but the sylvania coating is peeling off again

The only help I can offer is what not to do

Sorry, that’s all I got right now

This is from jace Weber from another site if you don’t want to buy a kit:

"Wet a rag with lacquer thinner, wet but not dripping… you don’t wanna drip any of the thinner on your paint. Make a few passes over the lens and this melts the haze out almost immediately. Let it dry. This is gonna look about 100% better right now if you stopped here. After it dried I took a 2000 grit Abralon pad and wet sanded the lens to smooth out any ripples left by remelting the polycarbonate with the thinner. Wipe it clean and put a good coat of Brasso on a piece of flannel and start rubbing. Rub it until it’s dry, then polish it with a clean piece of flannel. That’s it. It’s pretty amazing folks… beats paying a couple hundred per side for new assemblies and cheaper than buying a kit.

For what it’s worth, Brasso has been used to polish scratches out of airplane canopies for years and years. "

What I do is use Meguires Plastix on all my lights twice a year when waxing and have never had a problem with yellowing.

@db4690 - I have had great success with the Sylvania kit. I too followed the directions precisely and the amazing results have lasted almost two years. Nothing is peeling, the headlights are not yellow, but there is a slight haze to the lenses now. I will probably treat them again this August, two years after my original treatment, and hope for two more years. Maybe you got a bad kit. I bought the Sylvania kit based on the ratings in CR and it seems odd that they would rate it so highly, I would have such a good experience and you would have such a bad one.

To the OP, what car is this for?

@bloody_knuckles‌

I also bought the Sylvania kit, based on the CR ratings

I like CR, and read it regularly, but this is by no means the first time that their ratings have “failed” me

I’ve had excellent success using polishing compound with a drill-attached wetted-sponge buffing pad. I’ve done a number of them this way.

Truth is, any fine abrasive suspended in a soft media will work, and a good buffer pad (I prefer a sponge type) makes the job very quick and easy.

I agree with the same mountainbike but will add that this procedure will have to be repeated every few months. A new lens is the real fix but some lenses are either hard to find or very expensive.

I’ve had great luck with the kit that 3M puts out. The price is right and it seemed to do a good job.

That has nor been my experience. Every five years or so perhaps, if you live in the sun belt, but nowhere near every few months. The treatment does absolutely nothing to accelerate the oxidization of the lens, all it does in remove the oxidized layer on the surface.

I have tried rubbing compound, toothpaste, fine sanding paper and ever time topped it with PlastX polish. This was on a car with severely Oxidized headlights and I had to redo it in 6-12 months depending on how well I did the work.
My personal advice is that sometimes you find cheap headlight assemblies on amazon and if you are going to keep the car for another 5 years, it might be worth changing the headlights altogether. It is a safety issue too.

Did you do it with a buffer or by hand?

I’m curious as to whether the forum members who have this problem are in the habit of garaging their cars.
I ask because–while I have observed this problem for years on countless cars–none of my own cars have ever had this problem, and I can say the same for my brother’s cars.

Both of us garage our cars when they are not being driven.
Can this be the reason why we don’t have this problem–even after as long as 10 years?

I’ll admit I don’t garage my cars

My garage is too full of other stuff to fit a car in there

I’m sure many of the other regulars are in the same boat . . .

Mine are in the garage except when they are being washed and driven.

Mine spent its days outside… parked facing south… and its nights in the garage for the first eight year of its life. My previous cars for the past 17 years have all done the same.

My cars are mostly garaged, but my wife is always driving hers, that’s why I say mostly.

In my case, I have applied the products by hand, pretty strong though. Don’t have a buffer, have thought about the kits that have the drill adapter but not pulled the trigger yet.

Have a friend who had a detail shop and he probably had better results, but still longevity was not there. He offered to do mine for free but I didn’t want to make him work for free and the $150 he charges for this job would have gotten me a new pair of headlights anyway.

Still waiting for the OP to answer my question as to what car we’re talking about here? I think he/she is long gone. But if you hunt around, you can usually find very affordable replacements. Renewal methods are a waste of time in my experience. My suggestions are rock auto and eBay. If the website is still up, you can go to froogle.com and it will list the item you’re searching for from cheapest to most expensive.