DIY fibreglass repair, any tips?
DIY fibreglass repair, any tips?
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B-Reight

Original Poster:

905 posts

232 months

Wednesday 3rd June 2009
quotequote all
Oh noes, i've just managed to crunch my front spoiler/lip type affair on a deceptivley high kerb!

It has cracked in a couple of places but remains largely intact and attached.

Does anyone have any advice for fibreglass repairs? Will i be better off with polyester or an epoxy resin and do i need to prepare the existing surface in any way in order for the new layup to bond well with it?

Cheers
Ben

Edited by B-Reight on Wednesday 3rd June 19:49

B@man

1,486 posts

234 months

Wednesday 3rd June 2009
quotequote all
Get hold of a copy of "Automotive Glassfibre" by Dennis Foy.

Good book I learned a lot from it when I built my last kitcar.

Wedg1e

27,038 posts

295 months

Wednesday 3rd June 2009
quotequote all
A normal angle grinder will put a suitable serface for keying the new resin. You'll probably find polyester resin more than adequate for the repair; from kayak repairs I seem to recall that whilst epoxy will work on polyester, the reverse is not true. Either way you're only looking at a spoiler, I repaired mine with poly some years ago and it's still fine. What will take the time is getting the painted surface good enough. Whenever I try the usual methods I end up with sinkage banghead

adam quantrill

11,679 posts

272 months

Thursday 4th June 2009
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My big tip is to apply pressure.

What I do is - mix up the resin with the hardener and paint it onto the area you want to put the new mat on.

Then wet the mat with the same mixture an slap that on top.

Cut up a bit of thick PVC flexible sheeting (or a bin bag if desperate) and lay that over the top.

Then apply pressure to get the air bubbles out. Inside things like the rear wings I use an inflatable cushion - like the type you get for camping. For a spoiler, clamp on wood with G glamps or similar. This is what I did when I repaired my bumper recently.

After an hour it will have set enough, remove the clamps and wood and peel off the PVC - it doesn't stick to fiberglass resin.