gizzo wrote on 12/05/14 at 00:11:21:Hi Paul. Ignore this if it's teaching you how to suck eggs: Just a few ideas about fibreglassing the seat.
The chopped mat you're using is most likely designed to be used with polyester resin. The mat comes impregnated with a binder that dissolves in polyester resin. Epoxy doesn't dissolve the binder so the cloth stays stiff and is hard to wet out.
If you can lay your hands on some 6 oz fibreglass twill weave, try it. It drapes around curves brilliantly. It would probably be good for your seat. Loose weave would work well, too.
Dave mentioned vacuum bagging: You can make a vac pump from a coffee tin and aquarium pump for very little $$ and an outdoor bin liner as the bag. I used the fish pump for a while before I converted a nebuliser. I'll PM you a good link if you're interested.
If you can't pop that piece off your mould, you can try splitting it down the centre, pop it off in 2 halves then join them back together afterwards. I'd have carved the plug from white foam, glassed it and melted the foam out with acetone or petrol, but that's just me.
Anyway, good luck with the build.
Thanks gizzo, what you say about the mat makes perfect sense. I did buy that mat for a earlier project with polyester resin, but did not know it came with a binder that breaks down with only polyester resin. Any way its hardened nicely and has made a good strong base. I have got some Woven Roving which forms to corners really well, and will lay 3 or 4 layers of that to strengthen it.
Funny you should mention it I way only yesterday thinking this is going to be fun trying to get this out of its mold. My thoughts was to cut a hole in the bottom where the hump is and pull the guts out that way. Its only wood and foam.
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