Making a fiberglass mold

To make the mold:

Wrap the bumper in aluminum foil.

Put wax releasing agent (so you can cleanly take the new fiberglass off) I've seen PROs use McGuiar's Number 8 show room finish car wax (I'm sure  you can find some other products).

Put fleece on the bumper + paint it with resin so it gets tacky.

You can dip the fiberglass strips in the raisin to soak and then lay them down (very iportant and it helps minimize air bubles).  To make it smooth use a rubber roller.

Some people just dip the fiberglass srips and lay then down without the fleece (for a bumper I'd use the fleece).

Don't use bondo.  Use metal glaze or similar http://www.detailgear.com/index.asp?PageAction=VIEWPROD&ProdID=614 product.

It is a lot easier to work than bondo.

Make the mold first.

Then sand and use the glaze putty for small holes.

The glaze is a lot easier to sand than the bondo.

oonikfraleyoo - My bad that is what I was reffering to but forgot the name.  Rage Gold (same stuff Team Alpine uses to build those nice sick demo cars hommie)....

I guess you can do like I said in the first post dip the fg strips in resin and lay them down.

Mould - The inside is coated with a release gel and maybe they use FGlass or some ABS plastic mix and vacume forming presses (or liquid plastic).