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Old 08-04-2008, 05:08 PM
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gonzilla gonzilla is offline
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Location: Redondo Beach, CA
Join Date: Jan 2008
Posts: 164
Mein Auto: 02 540iT, 96 Carrera
DIY - Headlight polishing

I posted this on the E39 forum, but thought I might as well put it here too.

So, I had the cloudy headlight thing happening on my car. I read a bit on a few boards about how to deal with it. I decided to do the wetsanding thing and try PlastiX on it. Here's what I did and here are my results:


Tools used:

Starting with the polishing pads, and going clockwise...
1. Yellow cutting pad
2. Orange light cutting pad
3. White polishing pad
4. Water bottle
5. Optimum polish
6. Optimum compound
7. PlastiX
8. Aerospace 303
9. PC orbital
10. Craftsman telescoping magnetic light thingy
11. 3/8" ratchet
12. 6" extension for ratchet
13. 8mm socket
14. 2.5mm flathead screwdriver
14. 3m Assorted wetsand pack (has 200, 400, 800, 1000 grit)
15. 3m 1500 grit wet/dry sand paper
16. 3m 2000 grit wet/dry sand paper
(not pictured is a bucket of water, a 3m sanding block, a small piece of scotchbrite and some microfiber towels)

I decided to go ahead and take the headlights out to do this job. I figured it would be easier than taping everything off and trying to get the sanding block into tough to reach areas. So...

1. Remove the four bolts (the ones with red arrows) holding the headlight housing. Be careful not to drop the bolts at the back. If you do, use your magnetic wand thingy to try and fish them out (I got lucky and was able to find them. This is a view looking down onto the top of the driver side headlight.

2. Once you've removed the bolts, pull the headlight forward a little bit so that you can access the various plugs on the back of the housing. There are a lot. Use your small screwdriver to get some of them unhooked. Sorry no picture, but hopefully it's fairly self-explanatory.

3. Take the rubber "seals" off of the headlight housing. They are probably dirty and dry.

This one you just have to pull up a little bit to get it to come off the clips:

The other one is attached by little plastic "nipples". Carefully maneuver it so you can get it unhooked from the nips without ripping it. Mine seemed glued down a little too, but it could have just been 7 years of sitting on the headlight.

Take those dirty things and wash them. I just used dawn. After that, treat them with Aerospace 303, or whatever your favorite rubber treatment might be. Set those things aside and get ready to sand.

4. Take your sanding block and a small piece of scotchbrite.

You're gonna sandwich the scotchbrite between the block and your coarsest sand paper. For me, it was 400 grit. The scotchbrite just helps the sandpaper curve to the headlights contours a little better than a flat block.

5. Soak that block in a bucket of water for a few minutes. Get your water bottle ready too. Then, using a horizontal back and forth motion, go to work on the headlights. Don't go in circles, and don't go up/down. Spray the surface of the headlight constantly as you are sanding. Also, every make sure to dip the block back in the water bucket so the sand paper doesn't get gobbed up. I ended up using a small bit of force with the 400 grit. The sun damage didn't want to come off right away. Every once in a while, dry the light off and check out your progress. You basically want to see a really even surface, free from defects and as free from lines as possible. I found that the trick is to just use the weight of the block and use long even strokes across the entire surface of the headlight. If you had to previously use a bit of force, just make sure that you do a decent pass letting the weight of the block be the only force on the headlight. All in all, this pass took me about 20 minutes for 1 light. Here's what it looked like when I was done.

After you are satisfied that the light has a really even haze to it, you can move on.

6. Repeat the above with the next finest sandpaper. For me, 800 grit. The goal here is to remove any deep scratches that you might have made with the 400 grit. You're gonna keep going from side-to-side (actually you will go side-to-side for the rest of the steps involving sandpaper). I can't stress enough that the more time you spend on the sanding steps, the better your results will be. It's boring, but you'll be glad you did when it's all over. Here's after the 800 grit.

7. Repeat again and again and again... I used 1000, 1500, then 2000 grit.

after 1000 grit

after 1500 grit

after 2000 grit

8. After you have a hazy smooth finish on your headlights, you wanna polish the crap out of them. I used a Porter Cable orbital. First step was the yellow cutting pad and Optimum compound. Squirt a bit of the compound onto the pad and spread it around the headlight. I set the polisher at around 5 and worked about 1/3 of the headlight at a time. Afterwards, use a microfiber towel to clean off the compound. I took about 5 minutes for each pass with the buffer. Here's after the first pass with the yellow cutting pad/compound:

Following the same steps above, move on to a lighter pad. Here it is after the second pass with the orange light cutting pad/optimum compound:

Again, following the same steps above, move on to a lighter pad and a polish. Here it is after the third pass with the white polishing pad/optimum polish:

9. Put the PC away and sit down and relax for a second. You're almost done.

10. Using a microfiber towel or some sort of applicator, apply PlastiX to the headlight in a back/forth, side to side motion. I applied it to about 1/4 of the headlight at a time. It's fairly straightforward, just like waxing your car. Sorry no pic.

11. Put the rubber seals back on the headlight, plug everything back in and reinstall the housing. No pic, but c'mon, it ain't that hard!

12. Tada! You're done! Congratulations and hopefully you can see a lot better at night now. If I had to do it again, I would still take the headlights out of the car. It's just so much easier to see what your doing. I would also spend more time on the sanding process. I spent a decent amount, but I think I could have done better. Don't be shy when buying the sandpaper either, it goes fast. I think I may end up getting those Lamin-X things so I don't have to do this again for a while. But until then, here's what mine ended up looking like:

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