Any Fiberglass Finishing Guru's out there?

[david58]

I need some help here guys, this fiberglass one piece front end in kicking my butt. I have it sanded down to where I need to use a filler. As sturdy as this front end is it still has a bunch of flex to it. I have tried several times to feather the mat down and it is just like banging my head on a wall. I end back where I started, all I am doing is sanding off everything I just put on.
I talked to a friend that has a body shop and he says I need to use a flexible bondo, he said they even use bondo on rubber bumpers these days. I wrote down some of the info he gave me but forgot it at the shop when I left. Any help will be a great help.

[turbobaja]

I used some stuff called Poly-Flex on some of the fiberglass parts that needed filler. The guys at the local Wesco paint supply shop reccomended it specifically for use on fiberglass or in areas that need to flex some. Kinda spendy @ ~$30/pint, but really nice stuff to work with. I've come to the conclusion that all the fiberglass parts on my baja are going to be less than 'perfect' as far as finish goes. It would just take too much filler ( and work) to get them 'straight'. I've found that a couple coats of a quality hi-build sealer/primer followed by some carefull block sanding can yield a pretty smooth surface: good enough for a baja .

[david58]

Thanks Karl I ended up getting a gallon of Evercoat Z-Grip for $17.25. It is a flexible bondo and lite weight. Much easier to work with than fiberglass.

[craigvwdude]

No getting around it,, fiberglass just plain sucks!
Just about any body filler these days is flexible. The trick is not to get it too thick.
One of the problems with fiberglass is that no matter how many time you block it to get it strait, the next day it will be wavey. No getting around it. Fiberglass just moves around.
Just bondo it like anything else.
As for primer, you want to use a polyester primer. It actually uses fiberglass resin as a hardner. And the best thing about a polyester primer is that it doesn't shrink. It's the only primer that doesn't. All urethane, laquer, ect, primers will shrink.
And it filles like crazy! A bodymans best friend!

Craig

[volksman1066]

does anyone have any suggestions about spyder cracks???? i have them bad on a dune buggy project im doing

[Steve Arndt]

That Z grip works great. I have a gallon of it on my baja.... (okay, not quite a whole gallon).

[craigvwdude]

Voksman, you'll have to grind out the spyder cracks and glass over them.

[supa74]

i use that zgrip on nearly everything. that stuff works good. i use it for a milkshake also, = mix it in with fiberglass resin.