Headlight protection

Headlight bulbs, especially HID bulbs, put out a fair amount of UV. The heat coming off the bulbs also affects polycarbonate headlight lenses over time. Interestingly enough, polycarbonate blocks about 98%% of UV light. up to 380 nm. Sunlight is strong enough to progressively deteriorate initially the surface and eventually penetrate ever deeper. A friend has two Dodge Ram trucks, One is 12 years old, and the other one is 3 years old. Both vehicles are parked outside and see the same use. The older truck has pristine-looking headlight lenses, the newer truck's headlight lenses look pretty bad. I have so far managed to keep the plastic headlight lenses clear on all my vehicles. I use Plexus for cleaning and the same acrylic paint sealant I use on the car's finish to protect the headlight lenses. I have also used headlight film but it lowers the light output and, at least with thicker film, it increases thermal stress on the headlight lenses. I do park in the shade or with the tail end facing the sun. On the Mini I can cover the headlight lenses easily with two pieces of thin cloth held down by the hood.
 
SC Maintenance said:
I have heard others using clear enamel, and someone on this board just recomended to me Upol Clear #1 which can be had on Amazon - but I haven't tried it yet.
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I tried the UPOL #1 clear this summer on a set of headlights that I polished to near perfection. I applied 2 coats with 90 minutes cure time between coats as recommended by many detailing boards and was disappointed with the results. The UPOL spray urethane does not level well at all. The finish was uneven as the urethane seemed to dry much too quickly.

It appears that the clear coating preferred by professionals is now SprayMax 2K which is a catalyzed clear coat spray that must be used completely once the contents are activated. You must also wear a respirator and eye protection as it contains isocyanates.

SprayMax 2K
 
I have never found a so called sealer or clear coat that holds up for very long. When I finish polishing mine, I apply a coat of Collinite 476 or 845...holds up for 4-6 months...
 
All of it is a hit and miss chance. One method will likely give you just one year before it needs refreshing. Another might give you up to 365 days before you have to do it again.
 
The very best you can do for headlight restoration is a 2 part clear coat, I use Spraymax 2k Glamour since I don't have the means to use a spray gun. All of these coatings and clear films are temporary and have to be redone periodically. Since ambient conditions are never the same for any vehicle, your results may vary. But a 2 part clear coat I would consider to be as close to permanent as possible. It's applied thicker than your car paints clear coat is UV resistant.

I have been in the retrofitting game for a while and have restored a good amount of headlights. One of my first sets was my brother in laws Pontiac G6 headlight about 4yrs ago using Spaymax 2k. The car is general use runabout vehicle on their farm. It doesn't get washed, parked outside, it travels tons of gravel, sees salt/brine in the winter and is exposed to -10F-100+F. The headlights still look fantastic, it surprises me even that there aren't many chips considering how much gravel they drive. This is the best picture I have.

B34E4A0A-3120-424F-86CA-FAD06E476AFD.jpg



As far as my process goes, here we go.
-remove headlights
-dry sand with 340 until ALL of the factor coating is removed
-wet sand using 340, 600, 800. I use 1-2 drops of Dawn in my water to help with lubrication and cleaning, no more than 1-2 drops per 32oz
-between each sand paper grade, make sure the the previous rougher sanding marks are all gone
-after 800 grit, clean the lens with Isopropyl Alcohol or Automotive Wax and Grease remover for autobody applications.
-READ THE CANS INSTRUCTIONS!!!
-IMPORTANT!!! Make sure you are in an EXTREMELY well ventilated area or outside and a mask is recommended. This is very harsh compared to your normal spray paints.
-Mix the can. Now you only have 24hrs to work with the product. So either use the whole can for both headlights or do another small project while doing this.
-the first coat will be a light tack coat, I usually wait about 10-15min and spray a heavier coat after that.
-following coats are 30min intervals if I recall correctly.
-do not worry about a run or orange peel while spraying. See next step
-once cured (overnight or 24hrs), wet sand with 2000 then 2500 to remove any orange peel or runs. Afterwards use a polisher to get those puppies as clear as possible.

@vavavroom you are absolutely correct about HID's UV output. It's worse with aftermarket bulbs, but Osram and Philips have fantastic UV filtration and should cause no issues. The main issue that causes damage is poor UV filtration from aftermarket bulbs or ballasts any higher than 35w. It's not the heat from an HID bulb that destroys parts, it's the UV output. Higher wattage ballasts overdrive the bulb and increases the UV output. I would venture to say that the OEM Ram HID headlight has a different lens material than the Halogen one, but thats only speculation.

Halogens and HID's aren't far off for bulb surface temperature. But Halogen bulbs produce IR radiation which heats surfaces, where as HID's only heat the ambient air around them. Thats why Halogens will melt snow and HID's will only melt snow/ice to a certain point. Usually HID's will clear a small hole where the projector points out of the lens because of the UV output, but in heavy snow conditions that doesn't always do the job. It's still better than LED's can do in those conditions, thats a whole different discussion. Either way, I have retrofitted the majority of my past vehicles so you see which way I lean!
 
TacoFergie, I should have mentioned both RAMs have halogen headlights. It's of course possible that the polycarbonate is different and it's not unlikely that the newer material is of lower quality.
 
vavavroom said:
TacoFergie, I should have mentioned both RAMs have halogen headlights. It's of course possible that the polycarbonate is different and it's not unlikely that the newer material is of lower quality.
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I would suspect that the HID bulb may be of poor quality. Morimoto and NHK HID bulbs seem to be pretty good regarding UV filtration. The other possibility is a higher wattage ballast (higher than 35w) is being used. If it has an effect on the outer lens, then I would pull a bulb and see what the projector looks like because it's probably burnt.
 
PPF works for headlights when applied from new. I have had PPF on my 2001 daily driven BMW 540 and the headlights are still perfect (almost 22 years!). I have had to replace the PPF four times and probably due for a fifth as it gets pretty beat up from driving. But when removed, the lenses are pristine.

I have polished my Tundra headlights (never had PPF) and they would yellow and haze within about 4 to 5 months. Repolish and repeat... I applied a Sylvania coating about a year ago. It is just the protectant you apply AFTER you have polished the lenses. This was well reviewed in Consumer Reports magazine. It looked good at first, but now after a year its not looking so good. It has not hazed or yellow, but the coating is looking blotchy, like it is failing in places. I am considering repolishing and remove the Sylvania product and apply PPF instead...but concerned if PPF will work as well on a polished lens, or if it will haze or yellow anyway...

 
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I don't think the headlights on my BMW had yellowed in over 20 years. The car was driven daily but was otherwise parked in a garage for most of its life and when I bought it (at 3 years old) had the hood and headlights covered with clear protective film (with the thought it would protect them from breakage). But maybe it protected them from UV light.
 
PimTac said:
All of it is a hit and miss chance. One method will likely give you just one year before it needs refreshing. Another might give you up to 365 days before you have to do it again.
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6 one, half dozen the other...
 
f355spider said:
PPF works for headlights when applied from new. I have had PPF on my 2001 daily driven BMW 540 and the headlights are still perfect (almost 22 years!). I have had to replace the PPF four times and probably due for a fifth as it gets pretty beat up from driving. But when removed, the lenses are pristine.

I have polished my Tundra headlights (never had PPF) and they would yellow and haze within about 4 to 5 months. Repolish and repeat... I applied a Sylvania coating about a year ago. It is just the protectant you apply AFTER you have polished the lenses. This was well reviewed in Consumer Reports magazine. It looked good at first, but now after a year its not looking so good. It has not hazed or yellow, but the coating is looking blotchy, like it is failing in places. I am considering repolishing and remove the Sylvania product and apply PPF instead...but concerned if PPF will work as well on a polished lens, or if it will haze or yellow anyway...

Click to expand...
Tundra headlights are about as bad as Tacoma headlights for hazing. If the PPF that you use blocks UV, then in theory it should keep the lens below it clear. But that's only speculation, I'm no expert on PPF. The more you polish, the thinner the factory UV coating gets. At that point your down to bare, unprotected plastic. While you are protecting it with a film, I just don't know what the end result will be over time?

I'm about to sand and clear my 2015 Tacoma headlights since they are starting to get some haze on the top portion. For me the 2-3hrs of work and overnight drying is worth the time to not have to mess with for many years. I likely won't be getting rid of the Tacoma unless the next gen Tacoma is worth getting.

One thing to note about the process I posted above if you want to try it is that there is no reason to sand any finer than 800 grit. Some say to go to 1000 grit before applying the clear. But I, along with many others, have found that stopping at 800 grit has the same clarity in the end and has better mechanical adhesion than 1000 grit. Since a plastic adhesion promoter will reduce clarity, the clear is relying on its mechanical adhesion properties. Hopefully that makes sense.

grampi said:
6 one, half dozen the other...
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Personally, I prefer a permanent solution that takes a little rather than having to mess with it every 6 months or every year. Getting out all the equipment and prepping every time you polish, apply the coating and then waiting 24hrs to drive just sounds like a pain in the butt. Or you could just spend an hour more and not have to touch it for years to come.

I say permanent with some reserve. We all know that nothing is truly permanent. But I can pretty much guarantee that if you follow my process above (as many other pro retrofitters have done) that it will likely last 10 years or more. Since Spraymax 2k Glamour is an automotive grade 2 part clear coat that happens to be in a can, it will last as long or longer than your car's clear coat. If your car's clear coat lasts 20+ years that is far thinner that this will be applied, then there is no reason to believe that using this on headlights will last any less than your paint's clear coat.
 
TacoFergie said:
Tundra headlights are about as bad as Tacoma headlights for hazing. If the PPF that you use blocks UV, then in theory it should keep the lens below it clear. But that's only speculation, I'm no expert on PPF. The more you polish, the thinner the factory UV coating gets. At that point your down to bare, unprotected plastic. While you are protecting it with a film, I just don't know what the end result will be over time?

I'm about to sand and clear my 2015 Tacoma headlights since they are starting to get some haze on the top portion. For me the 2-3hrs of work and overnight drying is worth the time to not have to mess with for many years. I likely won't be getting rid of the Tacoma unless the next gen Tacoma is worth getting.

One thing to note about the process I posted above if you want to try it is that there is no reason to sand any finer than 800 grit. Some say to go to 1000 grit before applying the clear. But I, along with many others, have found that stopping at 800 grit has the same clarity in the end and has better mechanical adhesion than 1000 grit. Since a plastic adhesion promoter will reduce clarity, the clear is relying on its mechanical adhesion properties. Hopefully that makes sense.


Personally, I prefer a permanent solution that takes a little rather than having to mess with it every 6 months or every year. Getting out all the equipment and prepping every time you polish, apply the coating and then waiting 24hrs to drive just sounds like a pain in the butt. Or you could just spend an hour more and not have to touch it for years to come.

I say permanent with some reserve. We all know that nothing is truly permanent. But I can pretty much guarantee that if you follow my process above (as many other pro retrofitters have done) that it will likely last 10 years or more. Since Spraymax 2k Glamour is an automotive grade 2 part clear coat that happens to be in a can, it will last as long or longer than your car's clear coat. If your car's clear coat lasts 20+ years that is far thinner that this will be applied, then there is no reason to believe that using this on headlights will last any less than your paint's clear coat.
Click to expand...
The only things I get out is my can of rubbing compound and wax. Takes me 15 minutes start to finish. No 24 hour wait period, though your method does sound much more permanent...
 
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