After a few years, subjected to the elements, headlight optics tend to become cloudy either on the outside, which is the most frequent case, or on the inside. The consequence is a dimmer lighting of the road, likely to cause an accident. Except in very special cases, it is possible to resurface your optics to make them like new. You can do this with a commercial headlight repair kit or simple products that you can have at home.
Method 1 of 3: Prepare car headlights for restoration
Step 1. Locate the affected optics parts
See if the damage is on the inside or outside of the optics. If you notice moisture on the headlight but can't smell anything outside, you will need to disassemble the headlight to dry the inside of the optics and understand where the moisture is coming from. If you don't see any signs of mold and the exterior surface of the optic is slightly rough, this exterior needs repair.
- If you notice that the inside of the optic is wet, there is one or more entrances. Cleaning the exterior will only solve part of the problem. You will therefore need to clean the interior thoroughly, dry it and then seal the leak with a product or a seal.
- The presence of water inside a lens is never a good sign. Cleaning will be complicated, it will be necessary to find the origin of the leakage: in short, it is often better to change the optics.
Step 2. Clean your optics
Start by removing most of the dirt (bugs, dust, stains) with a sponge and warm water, then wash it off with car shampoo, applied with a soft cloth. Run your cloth horizontally from the grille outward.
- Because the headlight optics in the front of the vehicle get dirty very quickly (dust, mud, stuck or crushed insects, leaves). Clean them regularly and especially before resurfacing.
- There is no need to press hard on your optics to clean them, it is better to pass several times.
Step 3. Dry your optics, as well as the surroundings
Drying can be done with anything absorbent, such as a shop towel, paper towels. You can also use a hair dryer. Then protect the plastic parts and bodywork around the headlight with masking tape, preferably an adhesive specifically designed for bodywork.
Do not take just any duct tape. Some adhere too much, which could, when peeling, remove the paint or leave a mark
work carefully when buffing with the product. This one is always a bit stripping: avoid getting it on plastic, aluminum, chrome or paint. If you work in a garage and don't want your floor dirty, take the time to put a tarp under the work area.
Method 2 of 3: Use a headlight repair kit
Step 1. Purchase a headlight repair kit
These repair kits, for example, the 3M brand, are easily purchased at automotive supply stores. Make sure that the kit contains a complete set of sandpaper, a sachet of liquid polish, a polishing pad and instructions.
- If this is your first time collecting optics, buy a branded kit with instructions for use, because while the job is effortless, it is not without successive stages.
- If ever you did not have an operating manual, you can always go to the Internet, this is a subject that is often discussed (tutorials, videos).
Step 2. Use a water-based sandpaper
This special sandpaper, which is soaked in water, allows polycarbonate to be perfectly sanded. Sand to a smooth surface to the touch. The principle is to start with a very fine paper (grain 1000) and to continue with an increasingly fine grain (grain 2000). Dip your paper frequently in water to make it more efficient without being aggressive. At first you will sand horizontally and when you change grit you will sand the other way or diagonally.
- You can also sand from left to right with the 1000, then from right to left or diagonally with the 2000. Thus, the sanding will be homogeneous.
- Regular soaking of the sandpaper is essential, otherwise you will permanently damage your optics.
- As you sand, you will see milky droplets, this is normal, they are loaded with sanding particles. Continue sanding until the optics feel softer and the drops are less white.
the choice of sandpaper grit depends on the condition of your optics. With very hazy or yellowed headlights, start with a 600 paper. On the other hand, if there is just a thin veil of wear, without noticeable scratches, you can start directly with 2500. The higher the grain., the lighter the sanding.
Step 3. Rinse your optics
Simply rinse them with cold water, the goal being to remove both sandpaper residue and sanded particles. There should be no more white streaks. Then put a dab of polish on the polishing pad (or a clean flannel cloth), then rub the optics. Use circular motions so as not to leave marks and don't hesitate to apply a little pressure.
- Polish until you get a nice smooth and transparent surface.
- Of course, if you have large optics, you will need to add polish at some point.
Step 4. Let the product act for ten minutes
The treated surface will turn slightly white. You will then take a soft, clean and lint-free cloth to finish polishing. As before, rub in circular moments, pressing down fairly firmly. If there are any traces, continue with your final polish.
- Do not work in direct sunlight. Any polishing work on glazing or polycarbonate surfaces should be done in the shade to avoid streaks that are difficult to remove later. And then, your product will dry too quickly and will be ineffective!
- The final polish is done with a clean cloth, not with the one used previously.
Step 5. Apply a new coat of UV protection
It was removed during sanding and therefore logically, one must be put back with a suitable product. Take a workshop towel, spread a certain amount of renovator on it (read the instructions for the amount to put), then apply it in a single pass from left to right. You will start at the top of the optic and make several passes to treat the entire surface: your headlights are once again protected.
When you are satisfied with the result, remove the protections and see if there is some touch up to do and some tape glue to remove. If, on the contrary, you think that the headlights are not translucent enough, you just have to make a second attempt
Method 3 of 3: Restore headlights with household products
Step 1. Use toothpaste to repair your optics
As before, start with a good shampoo of the optics and a good rinse. Put the equivalent of a large dab of toothpaste on a clean cloth and rub your headlights until you get a near-perfect surface.
- If necessary, add toothpaste. During the operation, make sure that the optics and your cloth are always a little damp.
- This is a job that will take you 3 to 5 minutes for each lens. More, of course, if the impairment is marked.
for a perfect job, take toothpaste that contains an abrasive, such as silica. So-called "whitening" toothpaste works very well.
Step 2. Prepare a pickling paste
It will be based on sodium bicarbonate, dishwashing liquid. Mix the equivalent of 2 tablespoons of dish soap and the same amount of baking soda. Mix these ingredients well, they should eventually form a paste. Put a small amount of it on a slightly damp sponge and rub your headlights, adding more paste from time to time. Rub until the scratches disappear, then rinse the white spots simply with water.
- To rub, make small circular movements not too strong, but numerous, the result is guaranteed.
- This method works well for well marked optics. This may save you money by not having to buy a commercial restoration kit. Nothing is less certain, however!
Step 3. Soak your optics in a vinegar bath
Thus, both sides (interior and exterior) will be cleaned. Disassemble your optics (polycarbonate part), then immerse it completely in a large container full of white vinegar. Leave them on for a good hour, then remove them and wipe them with a sponge to remove all surface residue. Rinse them off with clean water, pat them dry, then put them back as they were.