Post from my blog. Thought you guys would like it... http://www.mioutdoorguys.com/?p=234
Here's the post below for those that don't want to click:
Ever see a car parked with cloudy, yellowing headlights? Or maybe you have a vehicle with this issue yourself. The kits promoting that they can clear headlights and restore clarity to them do work, but in my experience the clarity does not last long. I only got a month or two before my headlights became cloudy again. The cloudy lights greatly diminishes light output from the bulbs and can make driving at night difficult and dangerous.
I stumbled across this method to produce stunningly clear headlights and keep them that way for a long time. It’s simple and effective, and it took me about 20 minutes per light.
The materials I used were all purchased at my local hardware store. The materials are:
400 grit sandpaper
800 grit sandpaper
2000 grit sandpaper
Spray bottle filled with water
UV resistant clear paint that bonds to plastic
Plastic or trash bag to cover paint
First of all, it is important to note that this will only work if the oxidation and pitting is occurring on the outside of the lens. You can tell by brushing your hand over the outside. If it is smooth, then this process won’t work for you. If it is pitted, then this process should work out. The process is quite simple. In a nutshell:
Wet entire headlight surface
Start with 400 grit paper and keep surface wet with water
Move to 800 grit and finally 2000 grit, keeping surface wet
Dry headlight and apply clear paint to lens surface
Step 1: Clean the headlights with automotive grade cleaner, aka car wash. Make sure there are no bug splatters or tar on the light. Basically you’re trying to make sure you are only working with the lens and no other debris that could scratch or gouge the lens beyond desire.
Step 2: Wet entire headlight surface with spray bottle. I used a sports drink bottle with the kind of top that you pop up and squeeze to get the water to come out. That worked well but I think wasted more water than necessary. Another option would be the type of bottle that would be used for cleaning products where you squeeze the “trigger” and water sprays out. This would probably be better in terms of water consumption.
Here is how my headlights started:
Step 3: Wet the 400 grit sandpaper and apply light to moderate pressure on the lens. Use a left to right motion when sanding because this will create horizontal scratches and will help keep the clear coat from running later. When starting this step you may see a yellowish discharge from sanding. This is the oxidation being removed from the lens. Keep the surface wet and sand the entire lens until the discharge becomes more white. This is the plastic being sanded. The lens should now be very cloudy. As long as it is evenly clouding along the surface of the lens, this is what you want. This step took about 5 minutes for each lens.
After sanding with 400 grit:
Step 4: Use 800 grit sandpaper in the same fashion as 400 grit: horizontal scratches and wet surface. You will know you are done with 800 grit when the lens starts looking clearer. Again, there should be consistent clarity across the entire lens surface. I spent about 5 minutes with the 800 grit on each lens. Repeat the same process with 2000 grit. When wet, the lens looks super clear. Unfortunately when the surface dries, it looks less than stellar. The wet look is a preview of what the lens will look like after applying clear coat. I spent about 10 minutes with the 2000 grit.
After sanding with 800 grit:
After sanding with 2000 grit and wet lens:
Step 5: Use a microfiber cloth to dry and clean the particles off the headlight. I performed a couple of cycles of drying followed by wetting to ensure there were no particles left on the lens that would be trapped in the clear coat. Next, apply tape on the paint or rubber surround around the lens and then tape some plastic or a cut up garbage bag around the lens. This step ensures that no over spray gets on your paint. This is honestly the hardest most tedious step because it requires some patience and being somewhat meticulous.
Prepped for paint:
Spray a light coat of clear on the lens. it may not look perfect, but that’s OK, because you will apply a second coat after about 30 minutes.
After 2 coats of clear. I went a bit heavy on the first coat and it ran a bit, so be careful not to spray too heavy.
I just use the 3M restoration kit that you can use with a drill. On my last pass with the 3,000 grit, I do the horizontal swipes. As for a sealant, I use a 50:50 mix of Minwax Helmsman Spar Urethane and mineral spirits. Apply with a blue shop towel (you know those awesome blue "paper" towels) folded up into a one inch square. It doesn't take much and one good application ought to last you a good, long while.
High Deet percentage bug spray on a microfiber towel works really good, spray on the towel and wipe. Removes the yellowing and lasts pretty long too.
dont use bug spray, just dont be that guy. Chemistry is not stong with the person who thought of that, nor the "after the video " affects lol. Use the propler polishing process and remove the yellowed coating, then reclear to protect the plastic from UV, theyll be better than new if dont correctly/professionally.