Author Topic: Headlight Restoration  (Read 5694 times)


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Headlight Restoration
« on: April 28, 2011, 10:59:54 AM »
Thought I would copy this to here.

Today's vehicles have plastic headlight assemblies.  They look great new.  But, the elements can take a toll on them pretty fast. 

OEM UV Protection is pretty weak and it's not long before you see many cars with yellow, peeling, or just plain dull headlights.

Here's a process that I have tried and it really works.

Car is a 2005 Grand Prix


Driver Side

Passenger Side


 - 400, 800, 1000, 1500, & 2000 grit sand paper

 - Bowl of water. Spray bottle of water. etc. Warm seems to make things easier too.

 - Mineral Spirits/Paint thinner

 - isopropyl alcohol for cleaning.(I used the Paint thinner myself.)

 - Minwax Helmsman Spar urethane (clear gloss)

 - Shop towel/Paper towels

 - plastic polish / compound of your choice (I used Prima Cut and 3M compound)


You can perform this restoration with the lights on the car, but you'll need to tape off all other areas to avoid scratching paint, plastic, chrome, etc.

I'd also suggest leaving the bulbs in or plugging the holes so you don't get water/dust inside the assemblies.

I stole the sanding pics from the site I got this from.

Sand the length of the light and in one direction.

When you begin you will notice the water running off to be yellowish.  Don't stop sanding until it all runs clear.  Otherwise you're only partially sanding away the old clear.  You need to sand it completely off and get down to fresh plastic.  You will be able to see the difference between the coating and the plastic the entire time, especially when the light is wet. 

After 400 grit wet sanding.

After 600 grit wet sanding.(I DID NOT USE 600 IN MY PROCESS BECAUSE I COULD NOT FIND ANY) I have great results without this grit anyway.

After 800 grit wet sanding.

After 1000 grit wet sanding.

No pic for 1500 grit.

After 2000 grit wet sanding.

Then use Prima Cut(or your compound) with a polishing pad.

Then 3M Rubbing compound(or lighter compount/polish with a lighter pad.  (I've seen results with just this compound and they seem to work. I used the Prima because I felt like a little more aggressive compound was needed before. But, that's just me. Although, I've had people tell me I've posted the best results they've ever seen.

After all your sanding and compounding is done you need to clean the lights.

Completely rinse them off and dry them.

Then you will need to wipe them down with isopropyl alcohol(I used paint thinner) to remove any oils left behind. 

Now it's time to apply the clear.

You will need to mix the urethane and the mineral spirits at a 50/50 ratio.  It doesn't take much to cover the lights.  I used a tiny cat water bowl and only filled up the very bottom and it was plenty. 

Take your shop towel and fold it a few times into a square. Then dip it into the urethane mix and wipe the light.  Following the length of the light. 

To get a nice even coat, wipe past the end of the light. Do not stop on the light. 

This step below is optional

Everyone told me I didn't need to do this, but I feel better about it.

After 4 hours of drying time, lightly wet sand the lights again with 2000 grit. 

Rinse and dry.

Then apply a 2nd coat of the urethane.

I would give at least another 8 hours to dry before putting them back on the car.

I would also not drive with them in the rain until 24 hours of drying.


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Onyx Dragon

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Re: Headlight Restoration
« Reply #1 on: April 28, 2011, 01:16:54 PM »
Great job!  Wish I had this thread when I had my GP.