Sorry, this will be a little long. I decided to paint the underside of my trunk and hood and both doors before the main body. I ended up priming the car with a 2K tinted primer/sealer. I sprayed the items when the temp was in the mid 60s. Everything sprayed pretty good with 3 coats of base and three coats of clear.
The next day when I set the parts in the sun I noticed a small nick on the edge of the trunk that would be repainted when I did the top side in a few days. For some reason I went back and looked at it really close and started picking at it on the edge with my fingernail. In a few seconds I scraped the paint off about two inches long.
This was on Saturday so on Monday I took the trunk to the paint dealer. He was able to peal a big piece off without much trouble. After a few calls to the national tech support guy they couldn't figure it out. I watched the flash times for the temp really good and set a timer. I looked at the parts really carefully before moving to the next coat. In the end they decided if I thinned the primer like a sealer and sprayed the sealer before the paint it would be fine. They replaced all the paint used.
I still had to get all the paint off the items painted. My wife was able to get about 3/4 of the paint off the underside of the hood with just her fingernails. I sanded on the trunk and that was not working out very well.
I decided to spray a test panel, as I questioned did I mess up. I sanded half the test panel primer on one side with 400 and the other with 600. The temp was 68 deg. I did the whole process, three coats of base, three of clear, and watched the times and made sure things were flashed before moving on, and gave extra time just to be sure.
The following morning I checked the panel. I was able to easily scrape the paint off down to the sealer with no problem on both sides. I was right on the phone with the national tech boss and within two hours the regional manager was at my house. He checked my pieces and the test panel. He had at least 10 years experience painting custom cars and ten years selling paints. In the end he believes it was bad paint. He mentioned that the dealer said the primer/sealer was old and that may have been the problem.
Today after chemically striping the underside of the trunk I was sanding on the primer and realized how really hard it was. I am really suspecting the problem is that the primer/sealer was old, and that is the cause of the problem. At this point I canít risk painting over the sealer without some testing. I am thinking of doing another test panel and painting some epoxy sealer over my sealer and then doing the base and clear and seeing if that sticks. At this point it would be really nice to get back to where I was before I sprayed this product. Now my wife says she hates the car.
Any experts out there with any opinions of how to proceed?