I have some old fiberglass, the clearcoat is peeling off and it has some nicks that need filled.

What type of filler should I use for the nicks, just the "normal" filler, or do I need some type of special fiberglass resin filler? These are NON-Structural areas.

As far as paint prep goes, the clear is flaking off, should I use a chemical stripper to remove the rest, sand it down, or what?

 

Nicks and chips in fiberglass panels can be repaired with typical polyester fillers. Peeling clearcoat shouldn't be repaired any differently on fiberglass than it would be on steel parts. Just sand and prep as necessary, then repaint. Don't use chemical strippers on fiberglass, unless it's specially made for fiberglass. The good stuff, like 'Aircraft stripper' is not.

 

Are you sure it's clear coat, not gel coat? Clear coat is used over paint, gel coat is the color layer applied first in the mold to get a smooth finish and add color/opacity to the outside surface of the part. Clear coat will have paint then primer then the gel coat under it. Gel coat will only have raw FG (golden tan color with whitish fibers in it) under it. If clear coat, it only has to be scuff sanded down to the color or primer, but be sure to remove ALL the clear coat, any left will likely fail and peel when repainted over.
If it's the gel coat that's failing, then you have a much bigger problem.

 

It is definately the clear coat, someone switched colors of the truck. The newer paints clear coat is flaking......

 

Likely two different brands or incompatable types of paint were used or recoat time/directions for the color was not followed.

 

Fiberglass is treated much the same as steel...here is a pic of a couple of fenders I painted for a friend. One of these had many high spots down in the actual glass/mat that had to be smoothed out. Once I got the fenders straight I used the same epoxy primer that I use on all my jobs, sprayed three good coats and then blocked it and painted it with BC/CC. Years ago I used a lot of Feather Fill which was designed to be used on Corvettes to repair cracks and crazing in the fiberglass. I guess that this would have been an option as well. Feather Fill is rock hard when it sets up and will hold out many ills of fiberglass as time passes.

 

OK,


I found one 2" long crack in the gel coat that has blistered/popped open, how do I fix it?


Grind it out and just use regular filler over it?

 

^^^


This is a different issue than the clear coat peeling off.