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      11-01-2023, 08:26 AM   #1
KenBNaples
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Stain under clearcoat

Hey all,

Anyone ever have a stain under the clear coat? I used a bug and tar remover on it and spaced out and forgot about it. Its left a blueish stain that seems to be under the clear coat. I can crape my fingernail on it and feel nothing. I've tried rubbing compound but that has no effect. I was hoping to get an opion on it before I started heavier solutions.
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      11-02-2023, 10:30 AM   #2
KenBNaples
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Anyone?
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      11-02-2023, 12:08 PM   #3
TNTMYM3
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If it has just penetrated the clear coat slightly then on the smaller stain area, I would first go with 1200g wrapped around a small 1” x 2” block and do an X pattern “low pressure” wet sand using a 50% alcohol and water solution for a few minutes, then go 1500g, then go 2000 and polish the area afterward to see what your results are. Hopefully it didn’t penetrate too deep but if it did just repeat until you learn how deep it went. The clear really doesn’t look all too discolored from your photos so I would say that just finding the right amount of depth to sand into and polish is your solution. Typically, a detailer that is familiar with cut and polish process can also be very helpful.

Last edited by TNTMYM3; 11-02-2023 at 12:18 PM..
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      11-03-2023, 07:52 AM   #4
KenBNaples
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Quote:
Originally Posted by TNTMYM3 View Post
If it has just penetrated the clear coat slightly then on the smaller stain area, I would first go with 1200g wrapped around a small 1” x 2” block and do an X pattern “low pressure” wet sand using a 50% alcohol and water solution for a few minutes, then go 1500g, then go 2000 and polish the area afterward to see what your results are. Hopefully it didn’t penetrate too deep but if it did just repeat until you learn how deep it went. The clear really doesn’t look all too discolored from your photos so I would say that just finding the right amount of depth to sand into and polish is your solution. Typically, a detailer that is familiar with cut and polish process can also be very helpful.
Thank you! I may just have a detailer do it like you said. I'll only go so far to do touch ups on my own. I did read somewhere that using a clay bar may work. I assume I could try that before sanding?
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      11-03-2023, 12:58 PM   #5
Ervin87
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Looks like improperly prepped surface prior to applying a base coat, then a clear coat.

You may need to have the bumper repainted. Hard to tell from just a picture, but if 1500 grit doesn’t remove it (it should be removed with just 2-3 wet passes), then that is not a stain on top of the clear.
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