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. 

[AG-R3]

Welcome to the club...   this happened 2 years after fresh respray (2004) ..  Only this fender and a bit of wrap around to the Dside headlight.  All prep for the premium paint  was over the top... 6 coats primer, 8 color and 10 clear.  It was a stunner until this happened.   On an upnote, you could drive it in the rain and no one would notice, but it was sidelined...

[Kodjo]

32 minutes ago, AG-R3 said:

Welcome to the club...   this happened 2 years after fresh respray (2004) ..  Only this fender and a bit of wrap around to the Dside headlight.  All prep for the premium paint  was over the top... 6 coats primer, 8 color and 10 clear.  It was a stunner until this happened.   On an upnote, you could drive it in the rain and no one would notice, but it was sidelined...

Bummer! Did you do something about that?

[AG-R3]

1 hour ago, Kodjo said:

Bummer! Did you do something about that?

I've owned this car (1970 RQA) since new and in 1993/94 started a make over.  It got the full treatment, body off, with most things addressed and updated everything to late 90's equipment. 350/330 SBC, 700R4, 4 wheel disk brakes, all new interior, including a 1989 Dash that was purchased from the Youngstown factory in 1997.  The paint process took over a year and the body was gone over quite a few times to assure everything was done well.   Paint was PPG, 2 stage using a Lexus color.  A lot of work...when it was buffed out a year later, it looked like a pool  you could fall into. Pretty nice.  First time in the sun after the reno was around 2001 and it was over 2 years and 4000 miles later that this blistering started.  

I hate to say it but I conferred with a "reputable" body shop and they agreed to fix the fender.  I took the shiny bits off ( also the Paxton) and drove the car over.  A week and a half goes by and I get a call about a problem with the fender.  "Come over and look at this..."   After I arrive, I am led through this massive place, to a corner in the rear when I see my car with the front and rear windows out and the body completely stripped of all that beautiful paint.  They say they had to strip the car because of a contaminant in the  bad fender.  Of course they never thought to call me first.

Then, they start a conversation about the paint problem isn't fixable and the only way to resolve the issue is to put a "new" front clip on the car. They know where there's a "donor car" and it can be done pretty quickly.....Like " Really??!!"  it sounds like it smells...  There's a bit more to this but I'll make it short.  After three weeks of pressing this issue, I told then to put it on a roll back and deliver it, back to my house.  After  a while, it was back in my garage, where it sat for 10 years while I made attempts to clear the fender of the stain that caused the blistering.  It was evasive, in that you could wash it off with lacquer thinner  and sit back for 5 minutes and watch it bloom back. It looked like an oil stain but never expanded farther than the Dside headlight opening and there was no issue with the original paint when this renovation was started. 

I had two other car toys to keep me busy and couldn't stay on top of this continuously, so occasionally I would mix up a batch of cleaning agents,  brush it on a 12" square, cover it with saran wrap and let it work to see what effect it would have.  I didn't know what I was dealing with but suspected silicone brake fluid.  A couple years earlier in the renovation  had installed a 4 wheel disk brake system (1998) and had to try a few different masters to get the pedal right. It was using  an aluminum master from a Corvette and the bump in the road was to find a reservoir that bolted flat vs the up-angle on the GM stuff.  I found a solution with 2 individual reservoirs that fit and moved onto the next stage.  Looked and worked fine and I could not see any leaks, but  if there was a leak and that stuff was flung around the engine bay by the fan of a hot running engine, it could have contaminated that side of the body.  I found no evidence of that happening, however, so  whatever caused this is a mystery.      

The car was finally repainted around 2014, but by then I was having health issues and couldn't put the effort into it as before.  It's been my "ship in a bottle" since then and still hasn't left the garage.