My original O.A.I hood has paint bubbling problems.The paint is new.It seems to do it when the sun hits it directly.Also engine heat.Should the hood be re-jelled?,Flex additive?,Anything different for fiberglass?Any Help?

 

Take it to a Corvette body shop. They are experienced with fiberglass and will repair it expertly. Standard body shops do little of this type of work and make rookie errors.

 

Fiberglass is a totally different animal from steel. Sounds like solvents are off-gassing.
Root cause usually stems from using the wrong prep or paint products. The solvents in said products are trying to escape (release) especially when warmed up...in the form of bubbles.Water/moisture will cause bubbles as well.

The panel will need to be properly stripped back down, gel-coated then brought back into prime & paint. I'm not a paint product or body expert so get an expert opinion. I've spent my life around Corvettes. I have witnessed this several times. Find a shop that knows fiberglass and how to match the nice new paint to the rest of the car.

 

I am wondering what "gel-coating" is. More resin maybe? That would be hard to sand smooth, wouldn't it?

 

Sounds like there may be some contaminates involved. Oil can even soak into the fiberglass from the under side as it is slung off of pulleys. This is a common problem in Corvettes above the air conditioner compressor as the seals tend to leak.

 

Slick Sand is commonly referred to "gel coat" It is a polyester based high solids fast build primer. Slick Sand It actually sands pretty easy but most restorers don't use it unless the fiberglass substrate is in terrible condition.

tc

 

Gel coat is easy to use and acts like a sealer between the fiberglass and topcoat. It sands like primer and can fill small imperfections like small pinholes. Fibreglast Development 800-838-8984 has high quality products and has a tech support. Looking at an original paint hood, it doesn’t look like the factory used a gel coat but would recommend using it on a restoration

 

The use of gelcoat became popular with the influx of reproduction fiberglass panels that are "hand laid" using polyester resin and mat fiberglass. There are typically multiple pinholes that result from this process due to tiny trapped air bubbles. You can cover pinholes, but they don't fill easily. OEM fiberglass (usually sheet molded compound or SMC) is press molded between matched metal form dies and pinholes are almost non existent. Epoxy primer and a good 2K urethane primer is all that is needed.

Mixing and shooting a catalyzed polyester based coating isn't exactly a novice practice. You will want to use a primer gun with a big tip you don't care about because the odds are likely that the material will begin to kick off before you are done and getting this stuff out of a paint gun once it begins to cure is a challenge.

tc