AudiWorld Forums - DIY: Headlight restoration

I am not a professional, and this is just a description of what I did to restore my headlights. This is based on using 3M headlight restoration kit. Feel free to use any tools you want to restore, but be careful and read the instructions following the kit you use.
If you have any questions or comments, please let me know and I’ll update the post.

Items used:
Spraybottle with clean water
Car shampoo or similar to clean headlights before starting
Microfiber cloths
Masking tape
1200-1600 rpm drill
3m Headlight restoration kit that includes:
1 Disc pad holder
6 P500 grit disc
4 P800 grit disc
1 3000 grit disc
1 Polishing pad
1 Polish compound

General sanding tips:
- Try to hold the disc as flat as possible against the lens. Holding it with an angle makes it easier to remove bad scratches but it creates an uneven surface and can produse really bad marks.
- Use light pressure. More pressure just produces more heat and you will have to wait for it to cool down. No time saved there.
- Be very careful with heat!!!! This is maybe one of the most important things to be careful about when doing this. If you use too much pressure, too high speed or keep sanding the same area for a long time, your lens will get warm. If your lens get warm you have just created a ton of more work for yourself. It will make bad marks or even melt the plastic. Remember to check for heat often, and take a break if the lens feel warm.
- Change to a new disc when it gets clogged or doesn’t sand anymore.
- Wipe off dust often, you don’t want to rub it into the lens again.

1. Clean the lenses with soap and water, and dry them.

https://cimg0.ibsrv.net/gimg/www.aud...1571a5b403.jpg

2. Mask and protect around the lens, at least two layers is advised to protect the paint and details around the lens.

https://cimg1.ibsrv.net/gimg/www.aud...4c555a930b.jpg

Extra step for VERY uneven lenses:
A previous owner tried to remove fog in the lens by heating it, and of course ended up with melting parts of the plastic. To sand that down I used some P600 grit and sanded it down manually.

https://cimg2.ibsrv.net/gimg/www.aud...7399f2647b.jpg

3. Attatch the disc pad holder to the drill.

4. Attatch the gold colored P500 grit paper to the disc pad.

5. Use medium to light pressure to sand away the yellowing, haze and surface defects. Continue to sand with P500 until you are happy with the surface, the next step has finer paper and will not remove the worst defects.

https://cimg3.ibsrv.net/gimg/www.aud...86293912d3.jpg
When it looks frosted and you are happy with the surface, continue to the next step.

6. Attatch the white P800 disc to the disc pad holder.

7. Using medium to light pressure, remove scratches from the P500 disc and reduce them to P800 scratches.
Just continue with P800 until it looks smooth and as little scratches as possible.

8. Attatch the grey P3000 disc to the disc pad holder.

9. Get your spraybottle with water ready. With this disc you need to keep it wet at all times. Start by spraying a mist over the lens and on the disc and apply more water before it gets dry.

https://cimg5.ibsrv.net/gimg/www.aud...f3d49aace4.jpg
Most of the frosted look should dissapear on this step.

10. Attatch the orange rubbing disc.

11. Apply polish compound to the disc, and apply it to the lens manually without starting the drill. If you start the drill with the compound on, it will just splatter everywhere. Apply more compound when needed and continue polishing until you are happy with the result.

https://cimg6.ibsrv.net/gimg/www.aud...5be30e0f96.jpg

12. Remove the masking tape and wash the lens and surroundings with water and soap.

https://cimg7.ibsrv.net/gimg/www.aud...051897c113.png

What result you get depends on several things.
- How was the pre-condition of the lenses? Bad condition is harder to restore.
- How did you handle the drill? If you do not hold it straight you may get bad results.
- Did you produce heat? That will make bad marks and possibly melt your lens.
- How patient were you? Genereally, the more time you spend sanding, the more scratches and marks will you be able to remove.