Over time, even the best automotive optics lose their transparency, covered with microcracks and yellowness. This is not just a cosmetic defect, but a real safety hazard, as light transmission can drop by 50-70%. Drivers notice that the road is illuminated worse at night, and oncoming drivers often honk, thinking that you have a high beam on, although the near one is on.
The main cause of turbidity is the destruction of the protective layer under the influence of ultraviolet light and road chemistry. The plastic from which modern headlights are made is subject to oxidation much more strongly than the glass of the last century. The solution to the problem is the mechanical treatment of the surface, where the key element is the polishIt can remove the damaged layer and return crystal transparency.
Choosing the right composition is not just a matter of price, but a complex technological task. The market offers dozens of options from different manufacturers, and it is very easy to make a mistake in choosing abrasiveness or chemical basis. In this article, we will discuss in detail what types of pastes exist, how they work and what is best for your case.
Why the headlights get cloudy and when you need polishing
Modern optics are made of polycarbonate, which is characterized by high impact resistance, but low resistance to external influences. The manufacturer coats the lens with a special varnish with a UV filter, which becomes thinner over time. When the protection disappears, the plastic begins to turn yellow and become covered by a network of microscopic cracks that scatter the light flux.
The need for intervention can be visually determined. If the surface became matte, rough to the touch or acquired a pronounced yellowish tint - the time has come. Ignoring the problem will lead to the fact that destructive processes will go deep into the material, and simple polishing will not help, you will need to replace the diffusers.
โ ๏ธ Attention: If condensation is visible inside the headlight or cracks reach the inner cavity, external polishing will not solve the leakproofness problem. In such cases, a comprehensive repair or replacement of the unit is required.
In addition, the degree of turbidity is affected by operating conditions. Cars, often parked in the open sun or regularly washed with aggressive chemicals at washes, are aging faster. Abrasive polishing in this case removes the upper damaged layer, leveling the surface to the state of a new one.
Types of polishing pastes: abrasive and chemical
All restoring compositions are divided into two large groups according to the principle of action. Understanding the difference between the two is critical to achieving a quality result without damaging the optics. The wrong choice can lead to the fact that the headlight will become even more cloudy or will be spoiled completely.
The first group is effluent. They work on the principle of sandpaper, only on a microscopic scale. They contain solid particles (aluminum oxide, diamond chips, silicon carbide), which physically cut off the thinnest layer of plastic. Such compositions are necessary for deep damage and severe turbidity.
- ๐ด Large-abrasive - used for primary processing, remove up to 5 microns of material, remove deep scratches.
- ๐ก Medium-abrasive - are used for finishing polishing after a large grain, remove matte.
- ๐ต Microabrasive - create a glossy finish, often used in one-step polishing for easy correction.
The second group is chemical (non-abrasive) polyroly. They do not remove the layer of plastic, but fill microcracks and pores with a special polymer composition. The effect of these is temporary (1 to 3 months), but they are great for maintaining the state of new optics or as a finishing layer after abrasive treatment.
The Secret of Two-Component Systems
Some professional pastes work only in pairs with an activator. The chemical reaction enhances the action of abrasive and simultaneously seals the pores of plastic, which gives a more durable result.
Selection criteria: abrasiveness and the basis of composition
In choosing polish It is necessary to pay attention not only to the brand, but also to the technical characteristics. The key parameter is the size of the abrasive grain, which is often indicated in microns (ฮผm) or conventional units (Grit). For headlights, unlike the body, more delicate compositions are required.
The base of the pasta also plays a role. The water base is easier to wash off and less aggressive, but dries faster, requiring frequent moisture of the surface. Silicone or oil base retains elasticity longer, allowing you to work longer without drying, but it is more difficult to completely remove from the surface before applying protective varnish.
| Type of pasta | Grain size | Appointment | Difficulty applying |
|---|---|---|---|
| Reconstructive | Large (3-5 ฮผm) | Removing yellow, deep scratches | Tall (you need a car) |
| Polluting | Mean (1-2 ฮผm) | Elimination of holograms, finishing | Medium |
| Protective | No abrasives. | Shine, hydrophobic effect | Low (manual) |
| Diamond (pro) | Nano-abrasive | Perfect gloss, durability | High (requires skills) |
It is important to consider the compatibility of the composition with subsequent protection. If you plan to apply a ceramic coating or liquid glass, you can not use pastes containing oils and silicones, otherwise the protection will simply not lie on the surface.
Top manufacturers and popular lines
The automotive chemistry market is full of offers, but professionals distinguish several brands that have proven to be stable quality. The leaders of the segment are companies specializing in child-raising, such as 3M, Koch Chemie, Rupes and Sonax. Their products have passed many years of testing in real conditions.
Products 3M Perfect-It is considered the โgold standardโ for beginners and pros. It is predictable in work, easy to control and gives an excellent result even with minimal experience. However, there are many fakes on the market, so you should only buy materials from official dealers.
- ๐ฉ๐ช Koch Chemie German engineering, excellent two-component systems for deep recovery.
- ๐ฎ๐น Rupes They are known for their ultra-thin finishing pastes, which give the effect of โwetโ plastic.
- ๐ฉ๐ช Sonax Offer good budget solutions in the all-in-one format for home use.
- ๐บ๐ธ Meguiar's - classics of the genre, a wide range from rough compositions to protective sealants.
Budget Chinese analogues or nameless pastes from marketplaces often contain uneven grain. This can cause you to get deep furrows instead of transparency after polishing. The savings on consumables in this case are unreasonably high.
โ ๏ธ Attention: Avoid toothpastes and GOI pastes for polishing headlights. They contain large insoluble particles that irrevocably scratch the polycarbonate, making it matte forever.
Application technology: manual vs machine polishing
The method of application directly affects the choice of pasta. For manual polishing, only compositions with very fine abrasives or chemical polishes are suitable. The mechanical impact of the hands is not enough to work the large grain, and you just smear the paste without getting the result.
Machine polishing requires the use of a polishing machine (rotational or eccentric). Here it is important to choose the right circles: foam for the finish and felt or hard foam for primary processing. The speed of rotation should not exceed 1000-1500 rpm, so as not to overheat the plastic.
The algorithm of the machine:1. Put a pea pasta on a circle.
2. Rinse at low revs (600 rpm).
3. Raise the speed to 1200-1400 rpm.
4. Move the machine slowly, without heavy pressure.
5. Control the surface temperature with your hand.
Overheating is the main enemy of polycarbonate. If the plastic overheats, it can swell, go in waves or change color. Polishing paste In this process, it also acts as a lubricant and cooler, so you can not allow it to dry completely.
โ๏ธ Preparation for polishing
Protection of the result: lacquers and coatings
After removing the damaged layer, the headlamp remains defenseless in front of ultraviolet light. If you do not apply a new protective layer, the clouding will return after 2-3 weeks, and in a more aggressive form. The protection phase is therefore the mandatory completion of the recovery process.
The most reliable, but difficult way is to apply a two-component varnish. He creates a new hard crust, identical to the factory. However, this method requires perfect surface preparation and varnishing skills, as subductions are possible.
More affordable options are ceramic coatings or special UV sprays for headlights. They create a thin film that blocks ultraviolet light. The service life of such coatings is from 6 months to 2 years, after which the procedure for applying the protective layer must be repeated.
Before applying protection, be sure to degrease the surface with an alcohol solution (isopropyl alcohol). The remnants of the polished paste will reduce the protection adhesion, and it will quickly disintegrate.
Without further protection, headlight polishing loses its meaning after a month. Always plan a budget to buy UV polish or ceramic compound.
Frequent errors in optics recovery
Beginners often make mistakes that negate all efforts. One of the most common is the use of dirty circles or napkins. Dust caught between the circle and the headlight works like a major abrasive, leaving deep risks that are hard to remove.
Another mistake is excessive diligence. Trying to quickly remove the yellowness, the masters put a lot of pressure on the machine or keep it in one place for a long time. This leads to local overheating and deformation of the shape of the headlight, which distorts the cut-off line and blinds oncoming drivers.
- โ Use household chemicals for washing before polishing (leaves a greasy film).
- โ Polishing on dry (paste should work in a moistened state).
- โ Ignoring the pasting of the body (abrasive dust will spoil the paint coating around the headlight).
Also, donโt count on the โmiracle remediesโ from the ads that promise recovery in 5 minutes effortlessly. Quality polishing It is physical labor and adherence to technology. Magic doesn't work here, only mechanics and chemistry work.
โ ๏ธ Attention: If after polishing the cut-off line on the wall became blurred or shifted, then the geometry of the lens is broken. The operation of such a car is prohibited, a replacement of the headlight is required.
hand-polished lifehack
If there is no machine, use a screwdriver with a nozzle under a circle and Velcro. This is cheaper than a professional tool, but allows you to achieve a good result with careful handling.
Can I polish the headlights with toothpaste?
It's not recommended. Toothpaste contains abrasives (calcium carbonate), the particle size of which is unpredictable and too large for polycarbonate. You will get a matte surface with a net of micro scratches, which will have to be long and difficult to fix by professional means.
How often should the headlights be polished?
With proper care and the presence of protective coating - once every 2-3 years. If the protection is not applied, you will have to polish every spring, but this thins the plastic. It is better to polish once qualitatively and cover with varnish or ceramics.
What is the difference between polishing and grinding?
Grinding is the rough removal of the layer with sandpaper (P1000-P3000) to remove deep defects. Polishing is finishing with pastes to give transparency and shine. Without grinding can not do with deep damage, but polishing is mandatory after grinding.
How long does it take to polish one headlight?
A professional spends 20-30 minutes on a single headlight, taking into account preparation, polishing and protection. At home, without experience, the process can take up to 1.5-2 hours on both headlights, including drying time and protection.