Clarity of the Yellowed Headlight Lenses was Restored by Polishing and Painting!

In the world of "polishing," the difference between the finished product and the polished product is often the result of a persistent work process.
"Oh?" Let's remember that the headlights with yellowed plastic lenses can actually "shine brighter" and more beautifully than ever before, thanks to the use of previously unknown polishing techniques.

Painted headlight lenses with no luck.

While glass lenses are rarely yellow, there are cases of resin lens models from the 1990s onward that have a yellowed surface and "no luminous intensity" in the headlight inspection for vehicle inspections. We tried to revive such plastic lenses by polishing and painting.
What are the results?

Polished thoroughly to flatten scratches, but~

Baflex is commonly used in Paint Pro stores. It is set on a special sponge pad, and its sharpness is outstanding. Many say it is an indispensable product for preparing the groundwork for paint polishing. Recently, though, some companies are selling it in bulk by mail order for sun-mechs.
After rinsing dirt from the headlight lens surface, spray water thoroughly and polish the surface with Baflex "Green". The black color gives a finer finish than the green, but this time, I used only the green color.
The polish is sharp and bites firmly, and the lens surface at the time of work is cloudy white with the shaved acrylic material powder. This polishing process is repeated.
Here we used a headlight lens for a 4-wheeled transporter, but if you notice the yellowing of a plastic lens, even for a motorcycle, you will want to refresh it as soon as possible.
When a lens with severe yellowing is polished with water-resistant polishing, a dirty brownish liquid flows out at first. After several rounds of polishing, it becomes a cloudy white liquid. By repeating such polishing several times, the groundwork is made to look completely matte & cloudy.
We have revived clear lenses several times in this way so far, and working on them while they are in a mild state of deterioration will slow down the subsequent yellowing deterioration.
It is important to practice the work as early as possible.

After masking, it's time to set up painting.

Finished with urethane clear paint, but masking is applied to the surrounding areas except for the lenses for curing practice. The headlight lenses, which would normally be clear, are completely cloudy because they are still polished with Baflex.
Model Create Maxi, the company we asked to do the work, told us that they could make the yellowing of the lenses less noticeable by using a light blue clear instead of the usual urethane clear.

The key is to make it light blue clear.

The headlight lenses were completely clouded white by the Baflex polish, but the paint was sprayed on and the clarity was restored in the early stages. At the stage of drying after the paint was applied, we could already foresee a good finish. I wondered how much the clearness would be restored. By making it blue clear, the yellowing will be less noticeable.
That said, it is a light blue clear, so there is no blueness to it. It was still a good atmosphere even if the blue was made darker.

Beautiful appearance and clear brilliance are restored!

Before work

After painting

Yellowing of clear lenses occurs on the outside of the lens, but in vehicles that are frequently driven at night, the brightness of the headlamps and reflected heat! However, for vehicles that are frequently driven at night, micro cracks and yellowing may occur from the inside of the lens due to the brightness of the headlamps and reflected heat. The headlights for the transporter we practiced this time were the same, and the difference is evident in the before and after pictures.

Photography Cooperation/Model Create Maxi

I have always been curious about headlight polishing and wanted to try it out. Instead of simply polishing the headlights, I tried painting the headlight lenses. In the passenger cars and transporters around us, there are many examples of headlight lenses that are supposed to be clear but have turned yellow over time due to deterioration. Not only for cars, but also for motorcycles, models from the 1990s onward have changed from glass headlight lenses to clear resin (acrylic resin type) lenses, and there are some cases in which yellowing is particularly noticeable.

In the automotive world, headlight lenses are increasingly being made of plastic parts. It is now commonplace for headlight lenses to be "made of resin" for collision safety and weight reduction of parts. However, resin lenses are prone to yellowing, which is a source of concern for parts manufacturers. It is not uncommon to hear that a new car purchased several years ago has already become yellowed by the time it is due for its second inspection.
So, they polish the lenses to make them clearer, but within a few months, the lenses are as yellowed as before. Such yellowing can be slowed down by "painting" the lenses.
Here is a report on how we tried to finish the yellowed plastic lens of a transporter headlight by painting it at our own risk.

Urethane resins used for body paint are known for their high weather resistance.
We spoke to Model Create Maxi, who asked us to put the work into practice.

When I say clear, it should not be urethane clear. Most clear can sprays are lacquer-based, so the solvent is too strong. When lacquer clear is sprayed on a resin lens, there are cases where the solvent reacts with the resin of the material, causing microcracks to appear in the blink of an eye. Even if we were to paint with urethane clear, it may accelerate the progress of microcracks on resin lenses that already have microcracks, so it is not recommended, he says.
In any case, I wanted to give it a try, so here, at my own risk, I polished the yellowed headlight lenses with Baflex and sprayed urethane clear over them.

The before and after comparison images were taken more than two weeks after the work was done. Although the car is ridden for a long time every day during the hours when the headlights are on, we were able to restore a fairly good degree of clarity and brilliance.
It seems to be effective to practice before the symptoms become worse.