There is something that we commonly see now. We see many car headlights which are cloudy, scratched and yellowed. You may wonder why these are more seen nowadays than earlier. This is because the automotive industry decided to move to plastic headlight covers from the glass. These are correctly called polycarbonate lenses.
There are multiple reasons for the headlight lenses to lose their complete transparency. The sun’s UV rays can dull the brightness of polycarbonate lenses. Acid rain and salt are other reasons. Debris from the road can also affect your headlight lenses if they are plastic. If you have halogen lamps or high-intensity headlights, the high temperatures that they generate can also be the reason to dull the headlight lenses.
Restoration Vs. Replacement
Though the restoration is not so difficult, you must understand why you can’t just go ahead and replace the lens. Most of the cars have a sealed headlight unit. This means that you cannot replace the lens alone. You will have to replace the whole unit. If you are using an expensive car, then the high-performance lamps are going to cost you a good amount of money. This is why restoring your scratched and dull headlight lenses is much better.
How Good Can They Become?
You may find it hard to believe, but you can restore most of the headlights to the original condition. You will have crystal clear lenses once the job is done. Even if the glass looks to be opaque, you can bring them back to a fine condition. Unless the plastic is completely yellowed, you can get your original headlight lenses back.
What work it will take depends on how bad the condition is. The more clouded and scratched it is, you will have to do more work. There are many restoration kits available for this purpose. But you can restore your headlights even without these kits.
Things You Need For Restoration Without Kit
You would need a set of things before you start your work. All these are already available in your garage.
- Polishing Towels
- A bucket of soapy water
- A pair of latex gloves if you have sensitive hands
- Masking tape with 1 to 1.5-inch width
- Plastic polish
- Wet and dry sandpaper in 600, 1200 and 2000 grit
- 1” by 2” sanding block
- 2.5” Velcro backing plate
- 3” polish pad in foam or wool with Velcro backing
Removing Superficial Scratches With Polish
If your plastic lens has only superficial oxidation on the glass, all you need is good plastic polish. You should not use the one for domestic glass cleaning because they contain ammonia which can discolor your lens. If you want to test whether the scratches will disappear with plastic polish before you buy it, then rub the area with a little toothpaste. If the appearance of the lens improves, then you can buy the plastic polish and polish it with your hands.
Sanding The Headlight Lenses
The best way to remove the damage that doesn’t go with hand polishing is to sand your headlight lenses. This works very well. You must sand the headlight glass with different grades of sandpaper. This will be followed by glazing with plastic polish. Before we start the process, you must clean the headlight lenses very well. The best way to do this is to use soapy water.
Clean around the lenses too. Then dry the whole area very well. You must stick the masking tape around the headlight to protect your paint. You must have sandpaper soaked in water for around 15-20 minutes to make them soft and easy to use. This will make them soft and easy to use. Remember to use the sandpaper only with a sanding block and not with your hands.
You will start the process with wet sanding the headlight. If there are scratches and opaqueness, then you can start using the 600-grit sandpaper. This will be followed by the 1200 and 2000 grit sandpapers. You must use a lot of water and keep the sandpaper lubricated well. You must sand only in straight lines and not in circles. Keep using water to keep the sandpaper soaked.
The scratches will be removed by the coarser sandpaper while the finer ones will help in removing the scratches left by the coarse sandpaper. You will see that the water flowing from headlights when you send is milky. This is only the cloudiness of the lenses that are coming away. As you sand, the water will become clearer. Stop in between and dry the lenses and see how well they are polished. Continue sanding till the lenses feel smooth to touch.
Polishing For The Final Outcome
You must polish the headlight plastic using a 3″ wool or foam polishing pad. You must use a battery drill that doesn’t achieve too much speed. Fast rotation will make the wool pads develop too much heat. Apply polish on the pads and begin polishing. You will see the polish disappearing. Apply a little more and continue polishing.
Once you see that the lenses are clear, you can stop the polishing. You must complete the process by polishing by hand using polish on a microfiber towel. You can apply auto wax to the lens to protect it from the elements.