Paint issues

[Kodjo]

I had my car repainted last winter. I did the disassembly, sanding, and bodywork myself, but a friend handled the spraying. Now, after a long period of heavy rain (the car is parked outside), bubbles are forming in the paint. Luckily, it’s only in one spot—right under the rear quarter window on the driver’s side. As far as I remember, there wasn’t anything special about that area when the car was stripped down. Any advice on what to do?

 

[ronmanfredi]

1 hour ago, Kodjo said:

I had my car repainted last winter. I did the disassembly, sanding, and bodywork myself, but a friend handled the spraying. Now, after a long period of heavy rain (the car is parked outside), bubbles are forming in the paint. Luckily, it’s only in one spot—right under the rear quarter window on the driver’s side. As far as I remember, there wasn’t anything special about that area when the car was stripped down. Any advice on what to do?

 

I would wait for a few months and see if the problem area gets bigger before stripping the area and repainting it.  I'm guessing that something penetrated the fiberglass before it was sealed/painted and it's just now showing up.  While it looks bad, I'm sure you don't want to redo it more than once.

[Gunslinger]

There was no silicone products used at any time on the body was there?  Silicone penetrates the fiberglass and leaches out over time keeping paint from adhering.  

[Kodjo]

No silicone in the barn. The problem is not the adherence but something that grew under the paint. 

[psdenno]

Did you use any chemical paint stripper on the area.  Is it the area where you did bodywork prior to the repaint?

[Kodjo]

We used sandpaper only, no chemicals. We used cleaner to remove dust and possible oil residue. I think the cleaner was thinner. 
 

We used a primer, 2k epoxy filler, 2 layers of 1k base coat and a top coat.