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      11-14-2024, 11:36 PM   #1
downunderbmer
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Uneven headlight fogginess after sanding

Hi, I have sanded both headlights, starting with 400 grit and working my way up to 3000 grit, using a rotary sander. The results are uneven with fogginess along the lower part of the headlight? What could be the reason for this and could you recommend a possible fix? Many thanks.
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      11-15-2024, 07:05 AM   #2
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I would say your rotary is spinning too fast, it creates heat that can smear the plastic of the lens.
Slow it down and let the grit do the work without heat.
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      11-15-2024, 08:59 AM   #3
tracer bullet
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Agreed. It could be uneven pressure as well. Grit and pressure both will change the effect of the sanding, so be sure to be consistent. I always finish any sanding with a particular grit with a light pressure.

Also be sure it's uniformly wet, if the inside or outside is dry with the other wet you could also get uneven results.

I'd also put a 2nd layer of tape down, it can be easy to burn through it accidentally with the edge of the pad while you're focusing on a different area.
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      11-15-2024, 06:56 PM   #4
Redd
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When you sand the headlight covers you're actually removing the top anti-UV clearcoat on the cover. The dull grey area is clearcoat that you have not sufficiently removed. You need to spend more time sanding those areas.
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      11-15-2024, 07:44 PM   #5
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ive messed with this before, these solutions just dont work great.
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      11-16-2024, 07:37 AM   #6
Raimo5
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Quote:
Originally Posted by Redd View Post
When you sand the headlight covers you're actually removing the top anti-UV clearcoat on the cover. The dull grey area is clearcoat that you have not sufficiently removed. You need to spend more time sanding those areas.
That. Seen it many times before. Old clearcoat is not fully removed.
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