fiberglass body repair

[jsohn]

How do yall repair dents in your fiberglass body tub? I have several areas where there are chunks missing, cracks, spider webs, and unused trim holes I need to fill but im not sure if I can use bondo or if I need to use fiberglass resin with cloth. If I use fiberglass resin, do I need to use the cloth if im just filling a tiny screw hole or dent? Any help would be appriciated.

 

[Scooter402]

Depends on the size of the hole, and the strength needed in the repair you're making. For a screw hole, body filler would do fine. For bigger dents/spiderwebbing, etc, you'll need to use either fiberglass cloth or gorilla hair. I'd at the very least sand off the gelcoat and fill it back in with gorilla hair. Bondo makes some that's called Bondo hair. Basically, it's shredded fiberglass strands in a compound that cures once mixed with the hardener. The only downfall to working with gorilla hair is it is a little difficult to mix, a little difficult to work into areas, and unless you're an experienced body worker, it's a little difficult to flatten out on flat panels. But it does make very strong repairs.

 

[jdarg]

Lets see some pics if you want real specifics.

I wouldn't use bondo, except to maybe straighten out a bit of waviness before painting. If you have a dent that isn't actually cracked, I'd just build it up w/ glass cloth/mat to fill the void again w/ maybe a skim of filler over the top once its almost perfect.

Epoxy is what you want to use to fill bolt/screw holes, etc.

For the big holes/cracks, the best repair is to cut out the bad stuff (cracks, etc.), feather the edges of the hole that's left 2-3" if its a big one, and built it up w/ cloth cut progressively a little larger O.D. You'll probably need about 8 of these pieces, each cut progressively larger to match the feathering around the hole. I would also put 1-2 layers of mat in there with the cloth. This will be the strongest possible repair. Just cutting up fiberglass and shoving it into the holes/cracks is the worst way to repair it.