If you notice that the headlights have dimmed and become worse shine, do not try to wash them – it will not work anyway. The reason of dimness is not dust and dirt. It’s all about small, sometimes microscopic scratches, which appeared on the surface. In this case, headlight replacement or polishing will help. By the way, you can cope with the latter option yourself. How to return car headlights to their former shine and transparency – read in our material.
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Why are the headlights dim?
Not so long ago, car optics were made exclusively of glass. The material transmits light well, withstands scratches and is excellent for cleaning. But its big disadvantage is fragility. Glass headlights break, forming sharp splinters, and it is an additional threat in case of an accident. Over time, manufacturers began to switch to a more durable material – plastic. Today, most headlights are made precisely from a special polycarbonate or acrylic.
However, plastic is softer than glass, so it is more sensitive to external influences. While driving, particles of pavement, sand, gravel fall on it. All this leaves visible and hidden scratches on the headlights. Their transparency worsens with time under the influence of ultraviolet light.
Headlights are also damaged by improper care: wiping with dry cloths, hard sponges, brushes, ice scrapers. All of these leave tiny scratches on the surface.
How to Restore a Headlamp’s Transparency
Restoring headlights is done by sanding and then polishing. The top layer of protective varnish with chips and cracks is peeled off, exposing the internal structure. You can leave it as it is, but in this case the effect of the procedure will only last 3 months, and then the headlights will fade again.
Therefore, it is worth applying a protective layer after treatment. Products with wax, varnish, polyurethane film, nanoceramics are suitable for this purpose. The final coating will preserve the result of cleaning, and the headlight will shine well for much longer.
Choosing a headlamp polish
There are special products for the care of headlights. They come in several varieties: some are a set of two preparations – separately for cleaning (with abrasive) and finish polishing. Others are universal. Such pastes simultaneously clean and polish the headlight surface. When choosing you must take into account the material of your headlights and their condition.
Polishes for glass headlamps
Glass is a stronger and harder material than plastic, so scratches on it are formed much less often. Typical damages are chips of varying severity and repairability.
Most often, the cause of deterioration of light transmission is ingrained dirt, dust, particles of insects. In this case, you just need to wash and dry the glass well.
Plastic headlights
When polishing, you need to take into account that working with synthetic requires great care. First of all, plastic should not be heated, as high temperatures are bad for its optical properties.
If you polish by hand, check if the plastic is hot. Periodically take breaks to let it cool down. And if you decide to use a grinder, make sure that the speed does not exceed 1500 rpm.
Preparing for Polishing
First of all, you need to assess the condition of the headlights and determine where the material is clouding: on the outside, inside, on one side or on the whole surface. If the plastic is cloudy on the inside, the headlights will have to be removed. If there is external damage, you can leave them in place. In this case you should mask off adjoining areas with scotch tape or masking tape to avoid accidental scratching of paintwork during polishing.
Polishing options
It is possible to return clarity and brightness to headlamps in different ways.
Manual buffing with paste
You will need paste, sponges, water and scraps of cloth.
Sequence of operation:
- On a washed and dried surface, apply the preparation, evenly distribute;
- Rub in a circular motion, avoiding heavy pressure so as not to scratch the headlamp;
- Rinse the preparation and dry the surface with a clean cloth.
Buffing with a buffing machine
- If you do not want to bother with headlights by hand, you can use a grinder, drill or screwdriver. You will also need paste, 2-3 circles, water, clean rags. The procedure is as follows:
- Apply polish to the surface, distribute it over the surface.
- Set the wheel with the coarsest grit on the tool. At low speed carefully go over the entire surface, trying not to linger on one area.
- Wet the headlight periodically with water to avoid overheating and cracking.
- Change the disk to a gentler one, and increase the speed a little. Repeat the operation. If you are satisfied with the result, remove the rest of the product, rinse the surface with water and dry it.
- Apply the finishing polish. Rub in the product using a disc with the most delicate coating.
- Remove product residue and wipe off with a microfibre cloth.
Polishing with sandpaper
Abrasives of various grit sizes, a bowl of water and clean cotton flaps are needed:
- Sand the surface with a coarse abrasive (600-800 P), often wetting it with water to avoid overheating the material. Do not press too hard, otherwise you will get deep scratches. Try to make sure that the surface is treated uniformly.
- After you have finished the rough cleaning, rinse and dry the headlamp. Repeat the operation, but already with softer sandpaper (1000-2000 P).
- Clean the surface from the product.
- Apply polish and rub it in with a soft cloth.
- Remove the remnants of the product. Refit the headlamp.
Polishing with solvent
This method is more expensive and requires some skill. You will need solvent (acetone or other agents), a metal container with a long spout and a power adapter, as well as gloves, goggles, and a respirator. Work outdoors or in a well-ventilated place.
- Prepare the headlight for treatment by scrubbing the surface with a machine or by hand.
- Pour the solvent into a mug, heat it up until steam forms.
- Bring the spout to the surface, treat with steam, moving at the same speed. The hot solvent will remove the damaged layer, and the headlight will become transparent.
- Remove any condensation residue from the surface, rinse and dry. Apply the finish coat.
Polishing with toothpaste
Many car owners consider a toothpaste to be a good analogue of car chemistry. If you decide to follow their example, consider that the method is controversial, and not all masters welcome it. Do not forget that you have to work with paste carefully, otherwise you can more spoil the surface.
Choose a neutral product: without bleaches and additional components in the form of oil and dyeing decoctions.
Procedure:
- Apply the paste to the prepared surface.
- Rub gently, observing one speed and light pressure.
- When the surface is clear, rinse with water and dry with a clean rag.
- Finish with a polishing agent to seal the result.
- You can use tooth powder instead of paste. Diluted in water to a mushy consistency, not dry, to prevent scratching the surface further.
Lemon polish
You can use both natural juice and citric acid. But in the latter case, it is better to dilute the preparation in a small volume of water until the complete dissolution of the particles. The procedure is similar to the previous methods: apply, gently rub, rinse and dry.
Polishing with GOI paste
This compound is excellent for working with glass headlamps. It is better to use pastes with different degrees of hardness. The coarsest, with coarse particles is #4. And the most delicate, suitable for finishing, is No. 1.
Before polishing, apply the paste with the coarsest abrasive to a cotton or woolen rag pre-soaked in cleaned gasoline. Then distribute an even layer over the surface of the cloth that will be in contact with the headlight. After that, wrap another flap so that the abrasive particles do not scratch the plastic.
Wipe the prepared headlamp for 5-7 minutes using first paste #4, then #3 and at the last stage #1. Remove the remnants and polish with a soft rag without paste. Apply the final coat, using a preparation with wax.
As you can see, you can restore the shine and transparency of your headlights in different ways. It is not necessary to go to a car service at all. The main thing is to choose the right preparation and do everything as carefully and consistently as possible.