Mantilgh
New member
- Dec 6, 2014
- 2,724
- 1
If you're sanding from #500 and up you should have gotten most defects on the exterior of the lens. Hard to tell without seeing it. Sometimes there may be yellowing or discoloration on the inside of the lens cover from heat off the bulb or a leak of water.
Yeah, that was what I was going to say. I have seem look cloudy on the inside and HIDs can cook them, at least poorly retrofitted ones can.
There is the possibility that you didn't remove some of the previous sanding marks for one or more of the grits. That's one of the reasons I sand 90* to the last grit, but I would think the spar would fill it in.
Some have had ok results with the spar method, maybe around a year or so. I use Opti-Lens and some have had bad results with it.
I do not have any experience with spar on headlights, just with woodworking.
I do believe you could/should stop sanding at a low grit to give the spar something to hold on to.
Wood finishes, especially outdoor ones, are trying to accomplish the same thing as paint finishes. Ie. UV, scratch, and chemical resistance.