In the past, automakers designed headlight lenses made from glass so they were limited in the size and shape they could produce. Since then, auto manufacturers began designing cars with plastic or polycarbonate headlight lenses. This modification mainly occurred due to the change in the design of cars—cars became lighter and more aerodynamic, plus plastic was by far less expensive to produce than glass. Today this plastic material is the chosen choice because it is very light and can be transformed into unlimited sizes and shapes to satisfy new car designs.
Polycarbonate has its advantages but also has its disadvantages—namely oxidation / discoloration. To the naked eye one cannot tell that these plastic lenses are actually a porous material that expands ever so slightly when it gets hot. Degradation of the lens occurs over time. Having your headlights on or being exposed to the heat of the day causes the pores to open allowing debris from the road to get in. Debris, together with a combination of environmental factors such as the sun (UV rays), smog, acid rain, car exhaust, and harsh chemicals used to wash you car can cause the plastic headlight lenses to become oxidized.
Plastic oxidation leads to lens discoloration, which transforms new, clear, bright, shiny plastic to a dull yellow tint that appears to be foggy, hazy, or cloudy. This process (oxidation), as described above, not only becomes an eyesore but also is unsafe. Because of the degradation of the plastic lens, less light passed through resulting in diminished visibility during night driving. The car owner either had to deal with these cloudy yellow, oxidized headlight lenses posing serious safety issues or purchase expensive replacement headlights costing hundreds or thousands of dollars.
We feel it is necessary to inform the public so that they may know and learn how to restore, clean, polish, and clear those cloudy, yellow plastic headlight lenses on their own without putting more money into the car manufacturer’s pocket. One can restore headlights to like-new condition by taking off the top layer of oxidized plastic. This can be achieved through polishing, wet sanding, or through the use of chemicals. Auto manufacturers would rather you go to them for a headlight repair (charging as much as $150) or headlight replacement ($100-$1,000). The top layer of plastic on the headlights contains a UV polymer that retards or slows down the aging of the plastic lens. Therefore, it is important to use a polish (containing UV polymers) or UV coating to slow down the oxidation or discoloration of the lens. Parking your car in the shade or garage, or maintaining the lens by washing, waxing, and polishing a minimum of every three months, could avoid damage to the headlight lens.
There are many companies that specialize in headlight restoration and one can easily find one by simply putting in a keyword phrase such as “cloudy foggy headlights” into any of the popular search engines like google, yahoo, or msn. There are two types of headlight cleaners / headlight restoration kits:
1. Basic Headlight Restoration Kit (for light discoloration)
2. Advanced Headlight Restoration Kit (for more severe discoloration)
Most headlight restoration kits work extremely well. Choosing a kit depends on the severity of your vehicle’s lenses. Most kits available online are very easy to use and do not require the use of special tools or training. Beware of kits that offer backing plates and drill attachments. While they may save time, they may cause irreversible damage due to various drill speeds causing burning or swirls in the plastic lens. First-time users should avoid these kits because it takes skill and practice to control the drill from making these mistakes and possibly slipping off and ruining a perfectly fine paint job.
In some kits like an Advanced Headlight Restoration Kit, they may even supply a small roll of blue painters tape to mask your headlight to protect your paint job during the restoration process. Along with both kits, one should receive a step-by-step brochure outlining how to clean headlights appropriately to obtain bright, shiny headlamps while restoring optical clarity to your lenses. Both kits should carry a satisfaction guarantee. It is also a great resource if the company has tech support for anyone that has questions while reconditioning their headlamps so trained technicians can walk you through the quick and easy process of headlight restoration.