Paint dark in spots

50Shep

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Hi, I’m having a frustrating issue. Im painting my truck panel by panel with a single stage paint. Randomly Im getting areas of darker paint. This is especially true if I have any kind of run. As soon as I try and sand even a small part of the run it reveals a darker color. Any type of trash does the same thing, it leaves a dark spot. Im not cutting through to sealer. I’ve tried sanding all the way to primer in those dark spots just do see what’s going on and there is still plenty of paint.

The only thing I can think is that im waiting too long between coats and the paint in the gun is separating. Anyone ever had this issue with certain colors?

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It's separating as it sits on the panel, this is not unheard of in a single stage. What brand of SS? Maybe it's going on too heavy or the reducer is too slow, how long is it taking for a coat to flash? You might be better off just clear coating it instead of fighting it.
 
Sherwin Williams :( Sorry, what do you mean by clearing it? You mean buy a base/clear paint? Or are you saying that clearing the single stage would fix the issue? Seems to be about 25 minutes before it’s slick. The instructions say 10 to 15 flash time. I’ve gone as long as an hour though. I thought longer is better.
 
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Temps were probably borderline 65 degrees. I’m using medium reducer. Maybe I need to warm things up a bit.
 
If it's taking 25 minutes to "hand slick," it might be a little to slow for conditions.

Sherwin Williams makes thousands of different paints. I was just trying to see if it might be one that is compatible with SPI clear. Clearing over single stage is not standard procedure but it's not unheard of, and it would help solve your problem if you can't fix it any other way.
 
Thank you. It’s Atx Sherwin Williams. Why would clearing help? You mean just clear over the runs instead of trying to cut them?

I brought the temp up and resprayed today. Came out good so I think you may have solved my issue.
 
Glad you solved it. There are some single stage paints that just can't tolerate a lot of sanding and polishing, and certainly not if there is a run. I think people tend to underestimate the difficulty of using SS, but it is superior in some ways because there is no weak link in the system the way there is in BC/CC.

One way to overcome the tendency for SS not to like a lot of buffing is to clear over it, but since you have fixed the problem we can leave it at that.
 
Cutting and buffing for the most part is fine. Amazing actually. The depth and clarity is beautiful. But…. Any type of run or sag is a no go and I have to respray. I’ll end up using more paint for sure. Respraying is hit and miss as well. My resprays tend to fisheye like crazy. Not sure I’ll ever do SS again but I’m learning a lot. Thanks again
 
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