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  View original topic: hundreds of pinholes in paint
bomberbob Sat Apr 03, 2021 5:28 am

I sanded all the orange peel out, went to buff, there are hundreds of tiny pinholes in the paint. Not sure if you can see them in the photo.
Go back to wet sanding and see if I can take them out without going through clear?
Or scuff it, and mask off the rest of the car and reshoot the panel??



Mike Fisher Sat Apr 03, 2021 11:59 am

Iím thinking youíre going to have to sand them out and clear the whole panel again. Strange itís just the 1 panel. Maybe it was contaminated with something?

raydog Sun Apr 04, 2021 10:34 am

I think pinholes are caused from the previous coat(s) of paint outgassing. In other words, applying your next coat too soon.

67ctbug Sun Apr 04, 2021 3:37 pm

Yeah that's solvent pop. Could be caused by the paint being applied too thick so the previous layers were off-gassing still when you re-coated.

jspbtown Mon Apr 05, 2021 6:25 am

I agree with solvent pop. Thats why I always extend the flash times well beyond the time suggested.

There is a BIG difference in time between the flash time and the recoat window so I always at least double up the flash times to make sure things are settled down.

bomberbob Tue Apr 06, 2021 4:45 am

OK, I don't understand why I would only have it on one panel. I bought some Meguir's buffing compound, the stuff rated at 105 to try and remove the holes. My son said its going to take sanding as the buffing compound,, even the 105 ultra cut is going to take forever. I have not done anything yet, weighing my options. If I scuff it up to put another coat of clear on it, what do I need to scuff to, 1000 grit? Is the clear going to go down into the holes, or is it going to just sit on top and I have voids instead of holes?

jspbtown Tue Apr 06, 2021 6:38 am

Quote: OK, I don't understand why I would only have it on one panel.

Well it could be that it was a flat panel that got more paint. Or it might have been the last panel you painted that was not quite off gassed yet? Or a combination of the two?

Its very frustrating for sure.

You can't just "fill" the pinholes with clear. You have to sand the panel flat and remove them. Then you can determine if you need to shoot more base.

bomberbob Tue Apr 06, 2021 10:13 am

OK I will put 1000 grit on the DA and slowly work it down. Hopefully I don't burn through. Base coat is water based paint, which was a dream to spray, but I had not counted on any rework on it. If I succeed in getting rid of the holes without burning into base, then I will spray probably two more coats of clear so I have enough thickness to sand off the new orange peel.

bomberbob Wed Apr 07, 2021 4:55 am

Update: scuffed the panel with the pinholes last night. Moved around to the other side to buff that. After a little buffing I noticed that panel also has the pin holes, so its not limited to one panel. Prior to the buff, I could not see those holes. Its almost like I have to buff it a little, then they appear. So the rework is a larger task than I thought.

Braukuche Sat Apr 10, 2021 8:30 am

bomberbob wrote: Update: scuffed the panel with the pinholes last night. Moved around to the other side to buff that. After a little buffing I noticed that panel also has the pin holes, so its not limited to one panel. Prior to the buff, I could not see those holes. Its almost like I have to buff it a little, then they appear. So the rework is a larger task than I thought.

Itís cause compound is getting in the holes and when it dries it turns white and shows up.
Been there before. It sucks ass. You likely will have to sand them out and reshoot. Try using thinner coats and allowing at least a half hour between coats.
Good luck.

Teeroy Sat Apr 10, 2021 8:44 pm

Did you spray the car in a real spray booth? You need the constant air flow to get water born basecoat to dry, unlike solvent base paints that will flash off by solvent evaporation.

bomberbob Mon Apr 12, 2021 4:41 am

Base coat isn't the problem. I sprayed that and then had a delay, had to lightly scuff it to put down the clear. It was good and dry when the clear went over it. If I remember right it was a 2 day delay. I do like the water based paint, thats all I will use in the future.



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