Maintenance :: Cleaning and Restoring Hazy Automobile Headlight Lenses
Are your vehicle's headlights yellowed, cloudy or scratched? You're not the only one. Unless you provide your car's clear light lenses regular attention, in 24 months or less they can deteriorate to the point of being totally opaque, making it very unsafe to operate your car in the dark and in reduced visibility conditions. The fix is faster than you might believe. The best thing is that you can restore this hazardous and ugly issue in just a few minutes. It's easy once you know the secret. Why Do Headlamps Turn Yellow and Dull? The issue is not caused by abuse or neglect, as you might think. It is an environmental problem. Without regular attention, UV light from the sun, acid rain, salt and road debris damage and dull all clear plastics, including headlight covers. If your vehicle has halogen or another type of highintensity discharge (HID) headlamps, the problem can be worse. These sealed beam units operate at high temperatures, further contributing to degradation and yellowing. What Is The Solution? The solution is a quick restoration job. Headlight restoration is a plastic repair process that takes away visible damage and returns clarity to the lenses. Even severe cases of yellowing, hazing, and scratches can be fixed in less than thirty minutes. You might be wondering why fix instead of buying new? Your headlights are a sealed unit, so you can't simply replace the outer cover. If you have an expensive car with performance lighting, replacement is very expensive. Restoration versus replacement can save you hundreds of dollars per lens, so it's well worth the energy. Plus, it's fast! What level results can you achieve? It may look hopeless, but chances are the damage is superficial. Even if your headlights are completely opaque, they can be fixed. As long as the plastic has not yellowed completely, you have a very good chance of total restoration. Experiment With A Gentle Plastic Polish First If the damage is not severe, you may be able to resolve it with a simple plastic polish from the auto parts store. I suggest trying this step before any other. It won't be wasted time or expense, either, because you need to use the product regularly to maintain your headlights. NOTE: Never use a household glass cleaning product like Windex on clear plastic. Household glass cleaners contain ammonia, which causes clear plastic to turn yellow.
If the plastic polish alone does not do the job, then you need to repair the damage with a ultra fine sand paper (2000 grit is very safe) and re-glaze to restore a clear finish. While it may seem difficult or complicated, it's not. Wet sanding is fast and easy. TIP: You can test to see if your headlights will respond to hand polishing with a small dab of tartar control toothpaste. Toothpaste is mildly abrasive. If the small test area seems to get better, then you know polish alone may be all you need. Wet Sanding & Re-polishing Procedure To remove the damage with wet sanding and re-polishing, you need the following supplies: Polishing towels Bucket of soapy water Latex gloves (if you have sensitive skin) Painter's masking tape (1" to 1.5" width is best) Plastic polish Wet/dry sand paper (600, 1200, 2000 grit) Sanding block (1" x 2" erasure works great) 2.5" Velcro backing plate for use with 3/8" drill or cordless drill 3" foam or wool polishing pad with Velcro backing If you require a pictorial guide, then have a look at my Guide to Detailing blog. Here's the procedure: STEP 1: Clean the headlamp lenses. A bucket of soapy water works best. Clean the surrounding area, too. Dry thoroughly. STEP 2: Use painter's masking tape to mask around the headlight. This will help protect your automobile's paint finish. This only takes a few minutes, so don't skip this critical step. STEP 3: Wet sand each headlight. First determine the amount of damage to each lens. If your headlight lenses are scratched or if they are completely opaque, you will need to start with 600 grit sandpaper. Sand thoroughly, and then progress to1200, then 2000 grit. If your lenses are not scratched and are only slightly yellowed, you can probably get away with using 2000 grit paper only. The first sanding step is where you will actually remove the scratched and cloudy layer of plastic. The finer grades of sandpaper are to remove the scratches left from the previous grit sandpaper. As you sand, your sanding water will turn milky. This is the damaged layer being cleaned away. Use plenty of water for lubrication and to keep the sandpaper clean. Keep sanding until the surface feels perfectly smooth. The drippings will become clearer as the damage is taken away. Dry thoroughly
between sanding steps to check progress. STEP 4: Re-glaze headlight lenses using plastic polish on a 3" polishing pad (foam or wool). First connect the Velcro backing plate adapter to your drill. Apply a small amount of polish to the pad and start polishing the plastic. As the polish begins to dissipate, add a bit more and continue polishing. Stop polishing once the lens is completely clear again. Finish with a final hand polish using a tiny bit of polish on a soft towel or applicator. STEP 5: Seal to protect. Use a good car sealant to reseal the plastic and protect from the elements. STEP 6: Maintain monthly with a quality plastic cleaner/polish. The products I recommend most are Plexus and Meguiar's PlastX. If maintained regularly, your car's clear plastic lenses will never need restoring again!