Recent content by GP49

I don't know the answer! BUT UV-cured adhesives have now appeared on the shelves of hardware and home-improvement stores with their matching UV lights; so MAYBE more such products will be coming to the market soon.

Sometimes you can't. If that's the case, try to do it on a cool day so solvent evaporation is slower (out of the sun, of course, and perhaps early in the day), get the paper towel very wet, saturated; and go back and forth, top to bottom, overlapping your strokes. You are trying to always...

It only takes 10-15 minutes to dry dust free. That does not mean it is fully cured and hardened, or that you should wash your headlights yet; but it should be safe to drive the car after 20-30 minutes. Definitely don't wax the newly-spar varnished lights; until they have fully cured the wax...

Assuming you are doing this on your own car...not as a business. ON MY OWN CAR I have stopped using spar. It looks very, very good after application but once it fails, as it inevitably will by turning yellow and/or cloudy or flaking off, it is troublesome to remove. I did find that I could...

Yes, it can be sanded off, too.

The easiest way I have found to remove the spar urethane is Simoniz Instant Headlight Restorer. I tried it a long time ago and it didn't work worth a damn on actual cloudy, yellowed headlights. But I tried it on spar urethane that I wanted to remove. Sprayed it on liberally, let it soak for a...

If you were using the spray previously, and in cool, damp weather, it is possible that evaporation of the volatile carrier in the spray caused localized lowering of the temperature, causing moisture in the air to condense and cause cloudiness.

But the reason why I asked: paint thinner, at least in the USA, IS mineral spirits, which generally does not attach the plastic of which headlights are made. That's why I asked him what kind of car was involved. Or perhaps a particular brand of paint thinner has something else in it, such as...

I haven't moved on!!! :props: What kind of car? Would help those who may be working on one, to know of its headlights' susceptibility to paint thinner.

Denatured alcohol generally has NO water but the denaturants MIGHT etch the headlight plastic, since there is no standard formula and different makers may use different solvents as denaturants to be mixed in. 92% isopropyl alcohol is 8% water.

Don't use lacquer thinner unless you have already tested it on other headlamps that were made with EXACTLY the same plastic formulation. Lacquer thinner often will dissolve the plastic itself. So will Acetone. In fact since "Lacquer thinner" can include any number of different chemicals, I...

Could try turning the headlights on high beam for a few minutes to drive off humidity. Also, as Ray said, the alcohol wipe might be the better choice for the final cleaning before coating, as alcohol is miscible with water and could draw out more moisture, if you allow it to dry thoroughly...

It MIGHT be fogginess deep in the plastic itself, or on the inside of the headlight. Or, has it been humid up your way lately, so that moisture is getting to the sealant as it cures?

I've got three gallons of Klean-Strip "S-L-X Denatured Alcohol" in the garage right now. It seemed to be OK when I tried it, so I bought a couple more cans. It could have been some variation in the plastic that made it vulnerable, too; but the Klean-Strip stuff didn't fog it.