Originally Posted By: LeakySeals
I have a hard time using abrasives at all. A headlight lens is made of acrylic or Polycarbonate. Polycarbonate and acrylic is susceptible to UV and oxidation damage. To protect against that they are usually covered with a UV oxidation resistant coating. Sanding the top layer would remove that, making it degrade faster in the future. I suppose that may not matter because its a mess anyways, but I still try to use an off shelf anti-oxidant cleaner and a less abrasive buffing compound first to see what happens.
It's that UV coating that deteriorates and caused most of the problem, should be outlawed... Most park lamp lenses do not have such coatings and hold up far longer than headlamps...
Above said, if you use a good paste wax three or for times a year, the UV coating will generally not deteriorate and get hazy...