Re: Fibre Glass Resin and Petrol
"rads" <firstname.lastname@example.org> wrote in message
> 99% certain this is a stupid question, given the existance of GRP fuel
> tanks, but the nagging 1% of doubt forces me to ask:
> Is fibreglass resin fuel(petrol) proof?
It depends on the resin. There are differing compositions of both polyester
and epoxy resin systems on the market, some are ok with petrol (I'm assuming
that's the fuel in question) and some aren't. I've used Crystic 17789
polyester resin in contact with fuel and it was ok, but you MUST let the
resin fully cure for around 4 or 5 days before fuel contact. if the fuel
contacts it prior to full chemical cure, it will just soften and make a
Crytstic 17789 is a 3-part resin, consisting of resin, catalyst and
accelerator. It cures by an exothermic chemical reaction and the mix
quantities are critical for strength. Too much catalyst or accelerator and
it can self-combust!! A safer and very similar alternative, visit your local
boat chandlery and get a gallon tin of pre-accelerated polyester resin,
comes with a small tub of catalyst and costs around £30. As long as you
leave it to cure fully, it ought to be ok. I made a bonnet for a hillrally
motor using it and it's been regularly splashed with fuel whilst filling up
with no problems.
Epoxy resins are also available that are impervious to petrol, but they tend
to be thicker in composition and are really intended for semi-automated
manufacturing processes, i.e. autoclaves and vaccum-bagging.