Fiberglass / paint bubbles

[Paul S.]

About 8 to 10 years ago i had a customer with a 67 ,he installed a whole front end ( it was a correct press molded unit , that a reputable fiber glass supplier sells [the supplier assembles all the pieces on the front end and sells it as one assembly] i won't name names but they are located in indiana.i never , ever had and any problems with this supplies fiberglass. My customer also bought and installed two quarters and a deck panel ( i know , the car required a lot of work) from the same source. All i did was matt the seams, block it , prime it with dupont 2k primer and paint it base /clear. Car came out fine . Last fall (8 years later) he brought it back and showed me bubbles ( looks like little bubbles like the "measles" just in the quarters and deck, not in the seams . He wasnt mad at me and we discussd a plan on how to fix it. We had the whole rear clip media blasted . ( which blew a lot of pin holes in the fiberglass) we then primed it with 2k prime , multiple times , blocked it ( didnt use any spot putty), and baked it. Painted the quarters and deck and the upper deck panel. Well now , 10 months later after the car being in the sun etc. Quarters and deck are doing he same thing , bubles( upper deck panel(gm part) is fine , it was all painted at the same time). I kind of remember hearing about this problem before . Any thoughts ?

[Stephen L.]

Re: Fiberglass / paint bubbles

I believe your answer is in the "similar threads" below, under "paint bubbles on replacement fiberglass". That thread addresses the same question.

[Michael H.]

Re: Fiberglass / paint bubbles

Those are air pockets in the fiblerglass, I had the same problem with that supplier about 20 years ago. I let me body sit outside for one year and then pop all the bubbles and that took care of the problem. That fiberglass needs to see the sun/heat so the air expands in the fiberglass so you can fix the bubbles.

Mike

[Bill W.]

Re: Fiberglass / paint bubbles

I agree with Mike hot sun (90+) will fix most fiberglass problems . My project has sat outside all summer shrinking . If it is winter I use tanning lights .