This evening I performed some tests on my "test subject"(old assembly) and I found using rubbing compuond with an electric random-orbital sander and buffing pad restored the lense to a near perfect finish.
The first photo I buffed half of the lense.
http://i14.photobucket.com/albums/a310/1979-bmw/320I017.jpg
http://i14.photobucket.com/albums/a310/1979-bmw/320I018.jpg

how come they look amber on the edges,but the rest clear? if you cleard them somehow i want to know what year there off. from my understanding they cant be cleared

no, i think he's talking about the finish of the actual plastic (like the finish on paint). you could kinda see the difference in the pics, where the yellow/foggy stuff is cleaned away.

the color in the E21 front amber lenses are embbeded in the plastic itself....no conventional cleaner/solvent will take out the color, only years of UV radiation will.

shh! i would have let him try :P hours of fun to be had. polishing, and polishing, and polishing........ :P

Actually in the 2002 section someone talked about dipping them in a solvent, glycerol or something. Whatever they use to make the jelly filling of donuts?
Not sure if it works but supposedly it leaches the amber out. :dunno

Mmmm.... Donuts... Haha.

Are both those pics the after pics? what did they look like before?

Block sand them with 600 grit to remove the lettering, then buff them to remove the scratches/pitting. My lenses and tail lights are smoooooth.

Many people have tried to bleach out front signal lenses with mixed results...

It seems that the earliest lenses ('77) will sun bleach but anything newer does not... I cannot confirm this as I have not worried about clear lenses at all, I just recall many topics on various forums over the past 2.5 years or so...

ken

Block sand them with 600 grit to remove the lettering, then buff them to remove the scratches/pitting. My lenses and tail lights are smoooooth.

can you post a pic of the finished product. im currious to see how it comes out.

can you post a pic of the finished product. im currious to see how it comes out.
I'll try to get some close ups tomorrow.

much thanks

Here are pics of my letterless lenses.

that does make a big difference. i think i might attemp that. i have to replace one of my tails anyhow from an accident. i think ill use then as a guinea pig for the new ones...