Daily Archives: January 6, 2012
This BMW 5 series arrived in the shop with head-lamps that were no longer as clear as they once were. You can see in the first two photos how the polycarbonate lenses have been degraded from years of exposure to the elements. While there are products on the market that claim to remove the haze and restore the clarity of the head-lamps, they really don’t work that well when the lenses are as damaged as these are.
In the third photo you can see the first step of the restoration process. Like with practically every other job in a body shop, the first step is sanding. In this case I am using a fine grade sandpaper to wet sand the lenses, thus removing the layers of cloudy polycarbonate plastic revealing the clear plastic underneath.
Wet sanding is just what it sounds like, sanding while the surface is wet. The water acts as a lubricant to prevent the sandpaper from removing too much material and it also washes away the sanding dust so that you can see if additional sanding is required. It is a messy job, but it is the best way to remove the damaged material from the lens.
The fourth photo shows the lens after the sanding is completed. Obviously the lenses are far more scratched than they were when the car arrived, but the cloudy, hazy material has been sanded away and all that is left is the fine surfaces scratches left by the sandpaper.
The next two photos, numbers five and six, show the buffing process. Where the wet sanding removed the damaged plastic from the lenses, the buffing process removes the fine scratches left by the sandpaper. The high-speed buffer is used with ever finer grades of polish to remove the surface scratches from the lens, leaving them gleaming like new.
The first question people ask me about this process is, “Couldn’t you just buff the lenses clear?” The answer is yes, I could, but it would take much longer. The sandpaper, as fine as it is, is much more aggressive in removing the dull and opaque plastic. The buffer with it’s much finer polish would eventually cut through the opaque layers, but like most jobs, time is money. The wet sanding allows me to deliver the same results in less time, saving the customer money.
The last three pictures show the head-lamps after the buffing/polishing process is complete. Not only do the head-lamps look much better, they will work much better as well, allowing more light from the lamps to actually reach the road.
The lyrics to Johnny Nash’s 1972 hit song I Can See Clearly Now comes to mind for some reason. I just need to change one word …
I can see clearly now, the
rain haze is gone,
I can see all obstacles in my way …
Click here to hear the hit song from November 1972 … a very good month and year. Ask me why some time.