Nick McPherson asked:
It was a dark and stormy night - and I couldn’t see a darn thing in front of me. Despite the headlights being on high beam, the light was swallowed up by the darkness. In the bright light of day, I took a look at my headlights. I figured they were dirty, but even after cleaning them there remained what looked like a dull yellow film.
On older cars headlights are all one piece, essentially big light bulbs. The lenses were clear glass. When you replaced a headlight you had a fresh new lens, so other than cleaning them, there wasn’t much to do. These days, headlights are usually lamps that are installed inside a plastic lens assembly. You may change the lamp inside your headlight, but the lens the light has to shine through stays the same.
Plastics age over time and can will change color or get scratched. This discoloration is the result of years of being blasted by dust, road grit and being bombarded with sunlight. Light from the lamps inside is diffused. The effect is like a flashlight with peanut butter smeared on the lens.
My car is a good vehicle, but it is old and well-used. I don’t like spending a lot of money on it unless I have to. On the other hand, I didn’t want to run someone over because I couldn’t see them. The solution was to restore the lenses by polishing away the damaged surface using abrasives and polish.
Most auto parts stores will sell a kit with everything you need. I bought one for around 15 dollars. It contained four sheets of wet-dry sandpaper, a soft flannel cloth, some plastic polish and good instructions on how to proceed. Wet/dry paper is specially made to allow you to sand or polish surfaces while they are wet. Miniscule particles are ground loose from the surface as you sand, clogging the spaces between abrasive particles on the sandpaper. Clogged sandpaper isn’t able to smooth anything. Keeping the surface wet allows particles to float and wash away as you sand and prevents clogging.
In this case, the grit of the sandpaper was very high, beginning with 1000 grit on up to 2500 grit. Furniture makers don’t usually use sandpaper much higher than 320 grit, so you can imagine just how fine this paper is. My lenses were only moderately damaged, so I started with the 2000 grit and began to wet-sand the lens. I methodically sanded and wet the plastic, keeping the surface flooded with clear water. I did not have to remove the lens from the car. A tip: If your sandpaper starts to feel slippery, that means you need to rinse the paper and probably the surface, too. Don’t be stingy with the water.
Once I had thoroughly sanded the lens with 2000 grit, I used the 2500. I rinsed the lenses clean and dried them an began the final step. I applied the plastic polish, buffing the surface to factory-new. I spent about 40 minutes on the job. The next morning driving in to work early in the dark, I could really tell the difference.
Considering that two new headlight assemblies can cost over 100.00 (not including shipping and installation), restoring the headlights was an easy money-saver. If you can scrub a shower or polish a silver spoon, you have all the skills needed for this job. Just visit your local auto parts store and ask about a kit for restoring your headlight lenses.
