Headlight Restoration-new UV sealant idea

[Part-timer]

does it take off swirl marks off too.. my rear and head lights got small swirls on it.

In my experience, this method will only cover up extremely light swirl marks.....the deep ones WILL show through!

[Gsuarez]

I am just planing to sand the headlamps, I will try this method

[pman626]

I used spar urethane a couple years ago, but I don't like it because it has a yellow tint to it.

It also fails and peels off in about a year.

2-part clear coat on sanded headlights seems to be more durable. You can get a non yellowing clear + hardener for $20 in a rattle can.

[light-bright]

I havr been using it for over two years. I do not see a yellow tint. If you apply more than one coat you might but it doesnt have to be thick. Also I have done my personal car in Sept of 2011 and mine is still in tact, clean, and clear. I use the car wash at the local station often and it is not touchless. I find it hard to believe that it flakes off or won't last unless you did something wrong. Unless salt or other factors play a role in it not lasting, I am surprised. I live in AZ with hot sunny days and like I said I don't wash my car by hand with kid gloves. If mine lasted that long as well as stayed clear, I don't know what the issue is.

Sent from my SCH-I535 using AG Online

[rmagnus]

.
This morning had a chance to give it a go. Prep'd the surface by wiping down with ipa. Mixed up my spar/ms to a 7:3 ratio. Folded up my scott towel, dipped in and began to apply.
.

Ok I've been absent from this mega thread for some time. Is the mixing ratio in vogue now 7:3 vs 50:50? And a foam brush is the preferred applicator?

What's the best way to control the mixing ratio and how much product did you use for 1 lens?

[pman626]

I havr been using it for over two years. I do not see a yellow tint. If you apply more than one coat you might but it doesnt have to be thick. Also I have done my personal car in Sept of 2011 and mine is still in tact, clean, and clear. I use the car wash at the local station often and it is not touchless. I find it hard to believe that it flakes off or won't last unless you did something wrong. Unless salt or other factors play a role in it not lasting, I am surprised. I live in AZ with hot sunny days and like I said I don't wash my car by hand with kid gloves. If mine lasted that long as well as stayed clear, I don't know what the issue is.

Mine stayed on for a year, and when it peeled off, I realized that polishing the headlights before applying spar would not provide the bite it needs to adhere well.

Also, if you have a clear plastic cd jewel case, put some on and you will see the amber tint.


My next experiment will be putting on a cheap ppf-like film and testing longevity of that. I bought some on ebay for about $4. The film itself will prevent yellowing of the polycarbonate, but who knows how the film itself will perform. But for $4, what the heck. It will also protect against sandblasting, which spar won't.

[Part-timer]

Mine stayed on for a year, and when it peeled off, I realized that polishing the headlights before applying spar would not provide the bite it needs to adhere well.

Also, if you have a clear plastic cd jewel case, put some on and you will see the amber tint.


My next experiment will be putting on a cheap ppf-like film and testing longevity of that. I bought some on ebay for about $4. The film itself will prevent yellowing of the polycarbonate, but who knows how the film itself will perform. But for $4, what the heck. It will also protect against sandblasting, which spar won't.

It seems to me there are a number of factors involved in the amount of time that a coating will last.
The mix ratio for one.......the more spar...the longer they seem to last. I'm trying to work as close to 70/30 as possible(weather permitting).

The weather can make a big difference. (especially if its windy, I work outside and not inside a shop) Each day can be different. Some days I can use 70/30 and everything works just fine....while other days I end up having streaks so I have to thin the mixture more to get it to flow more evenly.

Another big issue, in my experience, is the angle to the sun and shape of the lens itself. A lot of cars have a flat surface on top of the lens which(even from the factory) seems to fail much sooner than other cars. The new coating you apply on those lights also seem to fail much sooner, no matter what type you use.

The polycarbonate itself seems to be different on different makes/models as well, which seems to somehow affect the durability of the coating. Some cars/trucks lights seem harder or softer and are more prone ending up with sanding/swirl marks unless you sand them very well.

Anyway....thats just my two cents(which may only be worth 2 cents...lol)

[Poormanq45]

I just polished the headlights on our mkv jetta over the weekend.

I removed the headlight assemblies completely to make things easier. I started at 800 wet, 1000, 1500, 2000 and then finished off with polishing compound. The lenses were perfectly clear.

I used a 50/50 mixture. The lenses were left face up in the garage to allow them to dry in a dust free environment and streak free. They came out absolutely gorgeous! Better than new!

Now to the bad, yesterday evening I was aligning the lights and noticed that the cut off is not as sharp as it used to be. There appears to be some random scattering going on that was not previously there.

Going into this I had the concern, the gloss is highly reflective, doesn't that reflect light back into the housing as well?

Feedback is greatly appreciated.

[feslope]

Now to the bad, yesterday evening I was aligning the lights and noticed that the cut off is not as sharp as it used to be.

Does this vehicle have HID headlights?

[Setec Astronomy]

Going into this I had the concern, the gloss is highly reflective, doesn't that reflect light back into the housing as well?

I don't think it's glossy at the interface of the layers...and I'm sure the lens was just as glossy on the inside as it was on the outside...and that didn't reflect the light back into the housing.

I think what you are experiencing is not reflection or refraction, but diffusion.

Wikipedia, the free encyclopedia)