My Brother in law does the professional Paint correction with some High-Tech ceramic product including headlights.

I read somewhere on the InterWebs that due to the manufacturing process, the outer layer of plastic should never be "polished" due to the process of taking the outer layer of plastic from the lens.

if that is true, what is the preferred method? And, if he coats the lense with a ceramic coating, does it matter?

 

I polished mine with no issues. The InterWebs you read were wrong.

 

Actually, the InterWebs was right, in this case. What they are saying is that there is a UV protection that is applied from the factory and sanding your headlights will remove that. The UV protection prevents your lights from turning yellow and cloudy quickly. Just like many things, it doesn't last forever and will wear out overtime, especially as your headlights get sprayed with road debris. IMHO, the best step to restore is to wet sand your headlights with 800, 1000, 1500, 2000 and 2500 grit sand paper and then polish them. At this point I'd suggest applying clear film protection. I've tried ceramic coating and other spray applications but they didn't last more than a year for me. Most clear films these days have UV protection built in.

 

3M makes a great headlight restore kit that contains all of the sanding discs and polishing paste for use with a power drill. And, as mentioned above, apply wax, some other UV protector, or clear film to save the lights from hazing up again.

 

Aren’t the headlights coated in clear coat?

 

Yea, but I think that is the coating that eventually wears down. I trust my BIL with his ceramic coating. I'm going to do that, and then probably install the clear film over it when done. Best of both worlds...

 

It will definitely wear down from abrasion and UV light. My point was that the only real solution is removing and reapplying the clear coat. I suppose ceramic and PPF might work as well but I don’t have any personal experience with that solution.

 

What's the logic behind applying a ceramic coating and then covering it with clear film, which already includes UV protection?

 

Just doubling up on the protection. These lights are unbeleivably expensive and I've seen lenses become weaker and crack / break with enough polishing. Ceramic will be pretty much the same as a clear coat. Then the film will further protect from UV but also from road abrasion. I'm trying to illiminate the need for repeated polishing.

 

You may be right. I worked in Auto Body years ago. At the time there was no such thing as a quality clearcoat for plastic products. AND, there was NO quality product that came from a rattle-can. I may be out of date on that but that will be forever embedded in my grey matter.

 

I'd suggest swapping up the application if you want to double up on protection. Having been bit by the detailing bug a few years ago, you'll never find professional detailers apply clear film to ceramic coated surfaces but the other way around. Ceramic coating creates a very slick surface designed to prevent stuff from sticking to it. You want to apply clear film to a virgin surface that's been wiped clean with alcohol solution for best adhesion. At that point, if you want, you can apply a ceramic coating to the clear film for added protection.

 

Mine were trashed from Florida sun and neglect. I polished the **** out of them and sealed them up with UV protection. Set a reminder on your phone to re-seal them every 6 months or so depending on conditions near you.