i recently aquired a fiberglass rear bumper. i want to mold it to the body. any good sources for info how to do it 'right'?
i have a basic idea ,but would like some references to help me.

thanks

robin

There is no "right" way to mold it into the rest of the bodywork, all methods will eventually crack and look bad since fiberglass and metal are not the same material. That is why you hear all the people talking about the metal GT flares, and not the $200 fiberglass ones.

If you want to attach it, use the stock attachment holes and glass in some supports on the back of the fiberglass to bolt into, but you'll be better served to leave it a bolt on bumper than a molded-on abortion.

I agree with George, 'glassing bumpers to the body is never a good idea. That being said, f-glass bumpers, flares, valances, and rocker panels never fit too well even new out of the box. They all need some work, but forming them into the body is not the answer. The joint always seems to telegraph through the paint or a cracks develop. I think it is easier to form the bumper to the car without actually attaching it to the car.
Keep it as a seperate piece but keep the joints/gaps tight.

Paul

hmmmm so then i need to re-glass the edges ,making them neater and smoother.then build brackets to attach the sides and make spacers to fit to the original mounts.
then get nice tight joints . i guess i'll have more work than i thought!

Robin

I have fiberglass bumpers on my car too. I molded the front on and am working on the rear. They were used when I got them, the edges had not been altered, and they fit like $hit !!! So .....like your sig. says .... It's MY Porsche .....so I molded them. Yeah it will probably crack later on down the road. But then again, the paint will probably get scratched or chipped or worse. It ain't gonna be no garage queen !!!

wow dave!

front bumper looks very nice.

did you glass it in or is that bondo?

-shag

Thanks Shaggy !!!
It is bolted in the stock locations, mounts built around front edge of front trunk to pop rivet the top of the bumper to, and then glassed. took me several months to get the way I wanted it, but it is there finally. been working on the rear for about 2 weeks, but don't have any recent pics of it yet.

truly amazing work.

no bondo at all huh?

how did you get the glass to stick to the metal?

-shag

Mar-glass is harder to work with but it works fairly well with transitions like that.

Used a 24 grit disc to rough everything up and give the glass a surface to cling to. Used cloth and resin to do all of the seam filling. Used "KITTY HAIR" for the contouring in all of the little spots. I may have 1/2 a cup of actual "bondo" on the front bumper.