I have been searching the forum for info to provide a little insight to a recent paint problem that has cropped up on my 85. The car was completely stripped and repainted about 2 years ago and looked beautiful . It normally stays garaged and only taken out for club events and short runs if weather permits. After about 1 year I noticed a small area on the front bumper where the paint appeared to be lifting. The area was about 3 fingers wide and approx 1.5 inchs in length.
As the area didn't seem to be growing and due to other things going on(read: life in general) I didn't take the car back in for several months. When I took it in the owner of the shop immediately took the car in to repair the problem. After doing a repaint on the front bumper I took the car back home.
About 2 months ago when attending a club event the car sat in the sun for a few hours and upon returning to the car several bubbles were noticed on both the front bumper and also the back bumper. When the car was first repainted extensive work was done on both bumpers to get rid of the waviness that is so previlant on the original bumpers.
So back to the shop she went, again both bumpers were prepped ,this time with a special filler that was touted to the shop as purpose made for this particular problem. Went Friday to check on progress and lo and behold the bubbles have reappeared.
The owner is getting with his supplier on Monday to address this problem and has stated that they will buy new fiberglass replacement bumpers if that's what it takes to resolve this problem.
It seems from searching this forum that the general opinion is that these bubbles are most likely caused by the solvent used in the prep of these bumpers is outgassing and creating these bubbles? Does anyone have a solution if this turns out to be culprit?
Thanks for any advice and recommentations.

 

I am of the opinion that without personal inspection and a more complete description of what materials were used, in what order and in what time frame our opinions would count for nothing. It seems your shop is commited to fixing this issue... I suggest giving them the opportunity to involve the paint supplier/manufacturer... you should get a positive outcome if you are patient and allow everyone time to diagnose and repair your paint.

 

IMHO it is one of these issues:
Car was stripped and contaminated while open, or body had contamination already and it wasn't properly dealt with.
Wrong products used or product failure. I'd be interested in seeing what products were used.
Trapped solvents, if primer,sealer, etc. was applied in heavy coats without proper flash time solvents will be trapped. If you smell primer while sanding, you have trapped solvents.
The fact that it didn't appear till the body got hot speaks volumes. I've seen jobs that looked great in the booth and shop but once the sun hit em they died back, bubbled, lifted, etc.
If I weren't doing body/paint and I was going to send a vette to be stripped and re painted I would make damn sure that each session of priming, etc. was baked or left to cure for a reasonable amount of time.
I bake substrate layers at 140 for 10-15 mins. then let sit till next day. In the morning I'll block enough to open the primer and let it sit longer, the last primer or sealer isn't baked. As a rule I don't bake top coats on vettes either.
There are all manner of mysterious paint problems that can be traced to trapped solvents. I use slow base thinner in vette overalls, let flash for longer than recommended, use slow hardner in clear. Spraygun settings must be sufficient to blow 60-70% of solvents off the RTS material before it hits the car or you risk trapped solvents. Leaving the booth running after painting an overall to prevent escaping solvents to fall back on fresh paint due to poor ventiation.
Spray~Gun