I was wondering if anyone knew of a fuel resistant fiberglass resin I could use for making a fuel tank?
Isn't all fiberglass fuel resistant? The reason I think this is that during the '70's lots of european dirtbikes had fiberglass gas tanks. They often broke during even minor crashes, so it wouldn't be my first choice, but I never saw an undamaged one or even one that had been repaired leak.
Fiberglass strands swell up when exposed to gas. Bayliner boats found that out the hard way when they were glassing in fuel tanks in the 80's. What are you attempting to build?
Check on the jockey journal. There has been some discussion about this. The additives in modern fuel (alcohol type stuff) are pretty agressive. There are some type of resins and tank coatings that are better than others.
I've used resin to seal many an old rusty tank on old bikes. I don't know anything about the strands swelling but it makes since that if the fuel can get to it it would swell. I'd say, as long as you have a good thick layer of resin incasing the matting it might be doable. I can't help thinking there is an easier way to come up with a tank though.
There are dozens of resin formulas. Do a Google search for a industrial supplier in your area and ask which should be used. We use to built tanks for a plating company in Baltimore and needed to buy special resins for that application. Even if I could remember the numbers, that was 40 years ago, and I know formulations have changed.
I have a 70s f/g flattrack tank on my Triumph. Was told by many that modern gas would soften the old f/g up. Haven't had a bit of problem though, so that tells me certain resins are better than others. As suggested above, M/C sites would be a good place to get more info.
THANKS guys great info, gonna check the jockey and try to find a local supplier, Oh by the way It's for a honda CB350 I'm gonna build into a 70's style Cafe' bike for the wife to ride
It seems to me, and this is just a faded memory in the back of my mind, that some of those dirtbikes used a rubber bladder inside the glass tank. That might be a solution.
I've glassed up holes in steel tanks with no problems but you gotta remember your soak your mat real well with resin. I would probably invest 30 or 40 dollars in some good alcohol resistant tank seal anyway to be on the safe side but you shouldn't really have any problems with it.
Can't say with certainty that any are absolutely 100% impervious to gasoline/alcohol, but a buddy of mine builds/repairs fiberglass motorcycle tanks. He uses epoxy resin, not polyester, and the results have been acceptable. Bob
Fiberglass will NOT stand up to the new gas today, just ask the boat guys...........many motors ruined because the alcohol in the gas eats the resins in the tank and ends up in the motors. You may be able to line the tanks with Kreem, a good idea on fiberglass anyway! http://boatingsailing.suite101.com/article.cfm/ethanol_fuel_problems_for_boaters check here...........
Check with Wicks Aircraft or Aircraft Spruce...... Some they sell is used in experimental aircraft for fuel tanks, I believe...
What you need is jeffco feul tank sealer....Ive used it many times (on aircraft) you can get it at aircraftspruce. Its not a slosh compound so you do need an open side of the tank to apply it. Then you seal the side with hysol "glue" this stuff cost alot and is only sold in larger packages than you will need. If its not done right it will leak...the sealer can not underlap the panels when glued togeather...the hysol must over lap the 2. You should go to a local airport or do a search and find someone in your area that is building a glass/composite airplane ...like a glass air or a lance air. Do a serach for your local chapter EAA.(experimental aircraft association) from my experience , these guys love to help out any fellow builders. If you cant find any local help PM me and ill help all I can from here.
Vinylester is more resistant to fuel than polyester, but is similar to working with polyester. Easier to mix than epoxies. http://www.aircraftspruce.com/catalog/cmpages/vinylester.php http://www.engineeringtoolbox.com/chemical-resistance-vinyl-ester-d_785.html
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