Restoring headlights

[aerog]

I'm restoring my "best British Sports Car" :wink: bit by bit. 2008 was some interior trim and new seats. This year I've got exterior trim to replace, brakes, a new top, and lots of detailing to do. This headlight stuff probably applies to some newer <span style="font-style: italic">real</span> British cars that have plastic/polycarbonate headlights (to be honest I like my MGB glass lamps, but that's another story)

The headlights on my Miata/MX5 have slowly started to haze over. The sun/heat actually had started to distort some of the lens on the driver's side. None of it was really serious but I thought I'd address them before it got worse.

I read up on some of the headlight restoration techniques and decided to just get a cheap consumer-level kit. 3M and Mothers looked good, I chose Mothers for $25. It comes with sanding pads in four different grades (800, 1000, 1500, and 2000 grit), polish, a small foam polishing ball made to be used with an electric drill, and a microfiber cloth.

It was hard to show the flaws in the headlights in pictures but this comes close:



I started with the driver's side (the worst of the two) by removing the trim bezel (an semi-permanent option on the Mazda and a pain to remove) and masked the paint & trim around the light:



Then the work begins. The kit comes with four grades of sanding pads that you use to wet-sand the lens. Each grade is followed by the next highest grade done 90° to the previous. The higher the grade, the longer you have to sand to cut through the previous grade's "damage". I planned ahead so the last grade was across the lens - which seemed easier to me.

As the sanding progresses the headlight turns more and more opaque and milky looking, leaving a wet slurry that I wiped down between grades:




Mother's instructions say to jump right into using their polish and polishing ball but I added an intermediate step. I used a dual-action buffer with a heavy foam pad and "Flitz" metal polish. It quickly brought the lens up quite a bit:



I finished up with the polish and polishing ball Mother's includes in the kit. Both products did a very good job removing traces of the wet-sanding and brought the lenses up to crystal clear:







Polycarbonate lenses are relatively thick and hard so this process isn't really difficult. I think it would work on other plastics pretty well with a lighter polishing pad a patience.

 

[Steve]

Thanks for passing that on, Scott. There are a couple of VWs in the family that are in need of this, so I see a little job for myself once the weather warms up enough to allow it......

 

[GregW]

Thanks for the write-up Scott. Now if you wire in a short circuit to the headlights, it will really <span style="font-style: italic">be</span> a British car. :wink:

 

[aerog]

I already have a nasty leak, isn't that close enough?