One of the headlights on my '02 Civic Type-S was really faded, yellow and scratched to hell. I was about to buy a new headlight assembly (at over £100) when @Chunkylover53 pointed out the 3M Headlight Restoration Kit. Here's the results of using it.
- Difficulty Level:
Originally I posted this as an update to my garage project log, but I thought I'd expand on it more, and add it as a guide.
Note most of the text here has been taken from a PDF version of the instructions that came with the 3M kit.
Before shots -
- Portable / wired drill (I used a Maplin branded 18v cordless drill). Instructions that come with kit recommend a 1200 to 1600 RPM drill
- 3M Headlight Restoration Kit
- Lens Sealant, such as this
- (recommended) Gloves and / or coveralls and / or breathing mask, as the sanding throws up a lot of dust
The first thing to do is to give the headlight to be restored a good wash.
Next thing you need to do is tape up the edged of the headlights, or the body panels around the headlight to ensure you don't damage the paintwork. The kit comes with some tape for this purpose, and even with me using 2 to 3 layers of tape, there was still some left spare.
(Sorry that I didn't take pictures at each stage of the process, but it is pretty simple and well documented in the instructions which came with the kit.)
Once you have headlight / bodywork nicely taped up, mount the Disc Holder from the 3M kit into the drill and ensure it is as straight as possible (to ensure that the disc does not wobble when sanding).
Attach the gold P500 grit disc onto the disc holder, ensuring it is properly centered
Using medium to light pressure, begin sanding to remove the yellowing and surface defects from the lens. A slow and steady back and forth action will be most effective. When the disc is clogged or no longer sanding effectively, replace with a new P500 grit gold colored disc.
Important Sanding Tips:
- Hold the drill flat or at a very slight angle when sanding on the lens. This will help control the tool and allow for smooth and even sanding. Do not use excessive pressure down on the drill or headlight lens.
- Do not hold the drill in one place while sanding. This can cause the lens surface to heat up and smear, becoming difficult to remove. Control the drill by moving at a slow, steady, even speed at all times across the headlight lens.
- Do not move the drill at a fast, erratic speed on the headlight lens.
- If abrasive disc becomes clogged or is no longer removing material, change to a new disc. Wiping the abrasive disc and lens frequently with a paper towel will reduce clogging and extend the life of the disc.
Wipe off the lens and inspect to ensure all the yellowing and defects have been completely removed. If yellowing, defects, or portions of the surface coating still exist, continue sanding with P500 grit gold colored discs until they are completely removed
(I will admit I was worried when the headlight took on this colour, but the instructions said to expect it (this is after using roughest sanding pad)
Important: The lens should have a white, evenly sanded surface that appears to look “frosted.” If any portion of the lens looks clear or glossy, continue sanding before moving to the next step. Extra sanding on this step will make the next step easier and improve the final clarity of the headlight lens.
Remove the P500 gold colored disc. Attach and center a P800 grit abrasive disc to the disc pad holder.
Using medium to light pressure, begin sanding to reduce the sand scratches from a P500 to a P800 grit scratch. When the disc is clogged or no longer sanding effectively, replace with a new P800 grit white colored disc. Make several passes over the entire lens to be sure the P500 grit scratches from the previous step are reduced to P800 grit scratches.
Wipe the lens, notice the scratches are finer. If any coarse scratches are visible, continue sanding that area with the P800 grit white colored disc until the coarse scratches are reduced. Extra sanding on this step will make the next step easier and improve the final clarity of the headlight lens.
Remove the P800 grit white colored disc. Attach and center a P3000 Foam Disc to the disc holder pad.
Using a spray bottle, apply enough water to dampen the gray P3000 foam disc and the lens surface before sanding. The foam abrasive disc can be used flat against the lens. Using medium to light pressure, begin sanding to reduce the P800 grit scratches to gray P3000 grit scratches. Important - Add a mist of water to the surface if it becomes dry while sanding.
On many lenses, a white residue or slurry will build up on the lens indicating you are reducing the sand scratches. Continue with 4-6 passes over the lens after you start seeing the white residue or slurry on the lens surface. If the lens does not produce a white slurry, make 10-12 passes on the lens. Extra sanding on this step will make the next step easier and improve the final clarity of the headlight lens. Avoid sharp edges or alignment pins on the lens to extend the life of the discs as this one disc will be used for any additional lenses.
Wipe the lens, you will notice the scratches are much finer and the lens appears somewhat clear. If any coarse scratches are visible, mist the area with water and continue sanding with the P3000 disc.
Remove the P3000 foam disc. Attach and center the orange foam compounding pad to the disc pad holder.
Dispense a 0.75 inch (about the size of a thumbnail) sized amount of the Rubbing Compound to the orange foam compounding pad. Before turning the drill on, smear the polish with the orange foam pad around the lens. This will reduce spatter. Too much Rubbing Compound will result in excessive splatter and added clean up. Do not run the foam pad dry.
Holding the pad flat on the lens, polish the lens until the cloudy haze is gone and the clarity is significantly improved. If additional clarity is needed or desired, add another 0.75 inch (about the size of a thumbnail) size amount of the Rubbing Compound and continue buffing.
If sanding scratches are still visible on the lens, repeat the steps above from the point of using the P3000 foam disc.
Remove the masking tape and wipe the lens using a clean microfiber detailing cloth
Wash any residual spatter from the vehicle using car wash soap and a soft, clean cloth.
For best results, don't hurry any of the steps above. For my headlight, it took me just over an hour to complete, but for a headlight in a worse state, it would take longer. Also, if you are happy at each stage that you have completed that sage, do not worry if you have spare discs from that stage - the kit supplies enough discs for each stage to cater for headlight in a variety of conditions. I had spare discs, and I thought my lights were bad to start off with.
Expect the process to take at least an hour.
When done, wait for 24 hours (try and ensure the headlight stays dry) and then wash and dry it again, and seal it using a lens sealant, or else within a couple of months, it will be faded again, as the sanding process actually removed the previous sealant that was on the headlight lens.
Final result on my headlight is shown below. An hour of my time and the small cost of the 3M Kit and sealant is much better than over £100 for a new headlight assembly