Are the headlights clear coated??

[mfergel]

I just used one of those 3M headlight finishing kits to removed 100's of rock chips in the headlight. Based on the sanding and the video for use you have to remove what appears to be a layer via sanding before you start the polishing process. I'm guessing this layer might be a clear coat? Should I clear coat them again (I'm cautious of doing so as most spray pant from a can isn't anywhere near as tough)?

 

[Synyster06Gates]

The sanding is to remove the imperfections. If you just used polish you'd be there for hours and hours trying to get the deeper rock chips out since there isn't much cut.

 

[mfergel]

Yeah but there was a definite layer is what I'm referring too. The sanding I get but as I sanded you could see where there was either a clear coat or the plastic is somehow created in layers (which I don't think is the case). Easiest way to describe the effect is if you were sanding away the color coat of your car and revealing the primer below. There was an edge to areas as they were sanded.

 

[Synyster06Gates]

Can't say I've ever seen that. Were your lights hazy or anything? It could have been a decent layer of oxidation that you were seeing. Maybe a previous owner installed a headlight film to prevent chips?

 

[mfergel]

Lot's of chips only. No oxidation. I should have taken a picture. My thought was that maybe there is a clear coat or another layer of plastic that helps in UV protection.

 

[one eyed willy]

i used 1500 and 2000 grit on my old gt500 lights to get rock chips out no problem. i dont remember there being a clear coat.

 

[cdynaco]

I added the LampGard from Weathertech so I wouldn't get any chips.

http://www.weathertech.com/lampgard/

 

[mrt2you]

I work in a body shop.
I have sanded LOTS of scratches out of plastic headlights.
headlights aren't "clear coated" but they have a special THIN coat of a UV inhibitor coating similar to clear coat.
you can sand and buff like you did. and the shine will last for a while, but the headlight will yellow pretty fast if you don't regularly re-buff or apply something to repel UV rays.
when I do my own headlights that look shabby. I sand the big marks, if there are any, out with 600 grit, then 800, then 1200, buff, then clean the compound residue and clear coat with a 2K clear coat.
if there aren't any big or deep marks start with 1000 grit.

you don't have to sand out ALL of the chips, just most of them. the clear coat will fill in the small marks.
also the headlight plastic is about 1/8" thick. if you sand to much you will weaken the plastic and it will spider crack easily from rocks hitting it.

 

[Synyster06Gates]

I work in a body shop.
I have sanded LOTS of scratches out of plastic headlights.
headlights aren't "clear coated" but they have a special THIN coat of a UV inhibitor coating similar to clear coat.
you can sand and buff like you did. and the shine will last for a while, but the headlight will yellow pretty fast if you don't regularly re-buff or apply something to repel UV rays.
when I do my own headlights that look shabby. I sand the big marks, if there are any, out with 600 grit, then 800, then 1200, buff, then clean the compound residue and clear coat with a 2K clear coat.
if there aren't any big or deep marks start with 1000 grit.

you don't have to sand out ALL of the chips, just most of them. the clear coat will fill in the small marks.
also the headlight plastic is about 1/8" thick. if you sand to much you will weaken the plastic and it will spider crack easily from rocks hitting it.

You seem to know your stuff when it comes to these headlights - you have any idea what's causing my spidering INSIDE the housing? Outside is just fine, but it is beyond fucked up inside.

 

[mfergel]

I work in a body shop.
I have sanded LOTS of scratches out of plastic headlights.
headlights aren't "clear coated" but they have a special THIN coat of a UV inhibitor coating similar to clear coat.
you can sand and buff like you did. and the shine will last for a while, but the headlight will yellow pretty fast if you don't regularly re-buff or apply something to repel UV rays.
when I do my own headlights that look shabby. I sand the big marks, if there are any, out with 600 grit, then 800, then 1200, buff, then clean the compound residue and clear coat with a 2K clear coat.
if there aren't any big or deep marks start with 1000 grit.

you don't have to sand out ALL of the chips, just most of them. the clear coat will fill in the small marks.
also the headlight plastic is about 1/8" thick. if you sand to much you will weaken the plastic and it will spider crack easily from rocks hitting it.

OK. That's what I figured. I was also reading that after doing the polish that they'd have to be done on a regular basis.

Is the 2k clear coat that you use just out of a can or is it being shot with an air gun? I'm always leary of spraying automotive items with canned spray paint since it typically isn't as hard. Unfortunately, due to the number of rock chips I had to sand that entire UV layer off.

 

[mrt2you]

You seem to know your stuff when it comes to these headlights - you have any idea what's causing my spidering INSIDE the housing? Outside is just fine, but it is beyond fucked up inside.

thanks for the compliment, I have been a body man for over 30 years.
I have seen this before. the cause? I really wouldn't know. my best guess is the UV rays from the sun have penetrated the plastic causing it to crack up.
or possibly there was some moisture on the inside of the headlamp. moisture combined with UV rays from the sun attacked the plastic from the inside.
unfortunately the only repair is to replace it.

 

[Synyster06Gates]

Yeah that's the plan. I have some OEM HIDs to replace them, but I may end up just selling those and getting replacement halogens.

 

[mrt2you]

OK. That's what I figured. I was also reading that after doing the polish that they'd have to be done on a regular basis.

Is the 2k clear coat that you use just out of a can or is it being shot with an air gun? I'm always leary of spraying automotive items with canned spray paint since it typically isn't as hard. Unfortunately, due to the number of rock chips I had to sand that entire UV layer off.

the 2K clear I use is from a spray gun.
there is some 2K clear coats in spray cans. you break the seal on the inside of the can, shake up well and spray. the clear will harden inside of the can in a day or so. you can make it last longer by placing can in a refrigerator. 2K products stored below 40* almost stops the catalyst from working, it will take a few more days before it hardens. DON'T put it in a freezer. paint doesn't like freezing temps for long periods of time
some auto body supply stores might have this. I think eastwood sells it also.

 

[SomeMichael]

Good information, thanks.

 

[mfergel]

the 2K clear I use is from a spray gun.
there is some 2K clear coats in spray cans. you break the seal on the inside of the can, shake up well and spray. the clear will harden inside of the can in a day or so. you can make it last longer by placing can in a refrigerator. 2K products stored below 40* almost stops the catalyst from working, it will take a few more days before it hardens. DON'T put it in a freezer. paint doesn't like freezing temps for long periods of time
some auto body supply stores might have this. I think eastwood sells it also.

Thanks. There's a auto body supply shop not far from me that carries the Eastwood stuff. Do you recommend I sand the lenses prior to painting them (I have a variety of polishing clothes up to 12,000 grit)?

 

[mrt2you]

i sand to 1200 grit, buff, wash the headlight to remove the left over compound that likes to hide in the pits. then mask and clear coat with 3 coats. then sand and buff the clear.
this usually works best after you remove the headlight.

 

[mfergel]

i sand to 1200 grit, buff, wash the headlight to remove the left over compound that likes to hide in the pits. then mask and clear coat with 3 coats. then sand and buff the clear.
this usually works best after you remove the headlight.

Thanks. Luckily I haven't put the bumper back on yet so taking the headlights back off is easy enough.

 

[mrt2you]

one other thing i forgot to mention.

the headlight lens is made of of polycarbonate, hope i spelled correctly.

this type of plastic doesn't like to be painted. the paint will stick. it just doesn't like wet coats of paint. if you paint it to wet the clear will start to attack and melt the plastic.
on the first coat spray the clear on light to medium wet. spray it on just until it starts to get wet. the clear will be a little bumpy.
the second coat paint a medium wet coat. spray until MOST of the bumps flow out.
the last coat can be full wet. spray until the bumps don't show up.

also the sanding grits i talk about are dry sanding with "A" grit markings.
if you are wet sanding with "A" grit rated paper use 1 grit finer when finish buffing, 1500 grit final sand.
if you are using "P" grit rated sand paper use 2 grits finer, 2000 grit final sand.

 

[mfergel]

one other thing i forgot to mention.

the headlight lens is made of of polycarbonate, hope i spelled correctly.

this type of plastic doesn't like to be painted. the paint will stick. it just doesn't like wet coats of paint. if you paint it to wet the clear will start to attack and melt the plastic.
on the first coat spray the clear on light to medium wet. spray it on just until it starts to get wet. the clear will be a little bumpy.
the second coat paint a medium wet coat. spray until MOST of the bumps flow out.
the last coat can be full wet. spray until the bumps don't show up.

also the sanding grits i talk about are dry sanding with "A" grit markings.
if you are wet sanding with "A" grit rated paper use 1 grit finer when finish buffing, 1500 grit final sand.
if you are using "P" grit rated sand paper use 2 grits finer, 2000 grit final sand.

Good to know. Thanks. Luckily if these get screwed up I still have my tinted ones to put back on. Visibility with the tinted ones has finally driven me crazy though.

 

[SNKPWR]

I can't remember the name but I found a polish-on UV protectant last time I did a set of lights, used the 3M kit then polished on the UV coating and it came out looking fantastic. Continued to look great for a year until I got rid of the car