cshaw07

iTrader: (14)

I'm not a body man and I hate doing body work, that said.. I am pretty good at it if I want to be lol but fiberglass is semi new to me. I know you mix resin and fibreglass matt to make the structure, but what is the outer coat? It seems pretty think and there's no glass mat in it. I've looked online and seen something about gel coat but it looked like it was primarily used on boats and stuff, not so much car bumpers. Or am I wrong?

I have an air dam for my 85 gsl and it's structurally in good shape, but some of that thicker outer layer is chipped off. Where it's missing I can see the fibreglass mat. Do I just buy resin and even it out or do I need to find that gel coat stuff (if that's even what they use)?

Someone, help a fibreglass noob out!

dougingraham

There are a bunch of different ways they mold stuff like this but one of the most common is to paint the mold with the white gel layer and let it start to cure. This gives a mirror surface finish that can be easily painted over. Then they add the glass mat reinforcement and wet that out. If your gel layer is chipped just sand back a little around the chip and treat it like a dented metal panel by filling it with your body putty of choice. Sand to match the contour, prime and paint to match. Nothing special really.

cshaw07

iTrader: (14)

the body filler wont crack with it being layed on fiberglass? the gel coat layer looked to be about the thickness of 4 sheets of paper, I usually dont like putting on putty that thick. But if it shouldn't crack i'll go for it. Makes my job a lot easier!

dougingraham

It depends on how much it will flex at that point. Like hoods you normally don't fill because it flexes too much but doors and other side panels are filled all the time. You can probably paint on a thick layer of the gel coat material and then try to feather it in but this is more difficult than the putty as it does not sand all that well. The fiberglass assembly is probably more rigid than the sheet metal and so you should have less problems here than when you fill dented sheet metal. Also you don't know exactly what materials were used in the construction of that part. You can try to contact the manufacturer if they are still around. They might have repair suggestions too.

I would test for material compatibility. Polyester does not stick all that well to epoxy but epoxy does work over polyester resins. Clean up an area on the back side and make sure the stuff sticks. Body putty is pretty tolerant of materials so I expect this is going to be your best bet.

cshaw07

iTrader: (14)

Thank you for getting back to me, looks like i'll try the body filler. It's right in the front of the air dam where the fog lights would go, I don't think it will flex there at all unless I hit something but then I dont think I'll be too worried about the body filler cracking lol