Auto body repair & detailing: 1958 Berkeley roadster, fiberglass body, paint lifting

Question
Can I clearcoat the paint stripped body, let it dry for a couple of days, and then paint the car over this clear coat. I keep having the paint lift from the fiberglass after the paintjob has been completed. This will be my fourth attempt towards stripping and painting this car.

Answer
Hi Randall Kaaz,

Are you trying to paint over bare fiberglass or does it have a gel-coat finish? Bare fiberglass is almost impossible to paint because when it gets sanded you have fiber exposed that acts like a "candle wick". When you paint on it the fiberglass absorbs the solvent from the paint and holds it till after the paint finish has dried and then the fiberglass fibers release the solvent and causes it to peel or lift from the body.

I would not use clear-coat for sealing this off because the clear will have a solvent in it and your just duplicating the problem. I would get a polyester fiberglass resin designed for automotive use and I would coat it with the resin first. Allow it to set up (a couple of hours) and then re-apply another coat of resin. Allow the second coat to dry overnight. The next day you can sand it lightly (just enough to get a sand scratch for primer to stick) and apply a 2K Urethane Primer. Apply about 3 coats of primer to get a good barrier of protection to stop solvent penetration. Make sure you allow plenty of flash time between coats. I suggest doubling the recommended flash time. For example if the primer calls for 15 minutes of flash time give it 30 minutes before spraying the next coat. After you have three coats of primer allow it to cure for as long as you can. If you have a garage and can let it sit for a couple of weeks before block sanding you would be better off. Doing this does two things for you. 1) It allows the primer to shrink all that it's going to and 2) The primer is fully cured to stop the solvent penetration from getting back to the fiberglass when you are ready to seal or paint. Try this and let me know how it goes. I truly believe this should stop your lifting problem.