Boat Forum / Building / April 2005

SORRY, I'm not sure if anyone has any  "fiverglass" tanks but what about
"Fiberglass" tanks?

My homebuilt aircraft has a fiberglass tank which has held avgas reliably
for thirty years.

When I asked Kern Hendricks (System Three's chemist/founder) about building
a gasoline tank, he said "Don't do it."  The aircraft tank was built back in
the bad old days when epoxy was deadly (and the builder died).  Epoxy
formulations vary.  Experiment.  You might also consider building a tank and
then lining the inside with "sloshing compound."

I tried building a tank for my wife's tiller and gave up.  I was trying to
mate pieces of steel with epoxy saturated fiberglass (to keep the mounting
holes and fittings) and whether the problem was at the interface or in the
pinholes thru the epoxy, I'm not sure.

Roger
derbyrm@NOSPAMearthlinkNOSPAM.net
http://home.earthlink.net/~derbyrm

I have fiberglass integral fuel tanks in my Ingrid 38. Many other Ingrid's
were build with fuel and water tanks of fiberglass. (My water tanks are also
integral and are coated with gelcoat.)

Since the hull is polyester resin as well as the tank tops, I had some
concern regarding etching or leaching of the resin. This concern was stemmed
from some warning from a diesel manufacture about micoscopic glass fibers
reaching diesel injector pumps. I raise this concern with my fiberglass
supplier, Tacoma Fiberglass. They contacted some fiberglass resin chemist
and provided a recommendation to coat the interior with an epoxy product.
The material I used contained some graphite which, I have found makes for a
very slick surface that is basically self-cleaning. I have yet, in 3 year,
to find any film build up.

HotRod Wrote:

I have built several plywood diesel tanks that were glassed and seale
with epoxy. It takes a special epoxy (don't remember what it was) an
had to be post-cured at about 140 degrees for 8 hours. They have worke
fine for the past 10 years but it was a hassle and not cost effectiv
when you consider the hours it took to build. We now go with custo
built aluminum tanks to fit what ever hole we put it in.
---Joel--

--
boatbuilder.org

I know it's possible for gas tanks, with the exception that todays
fuel had ethanot added which creates problems. So diesel should be
easy. I have seen recommendations from West System that you use
slightly less hardener. Evidently the recipes have you normally use
extra hardener in the resion to be sure and get a decent setup. Less
hardener leaves less unused resin in the mix to soften it. Just don't
use too little hardener

I guess I need to find out what epoxy I need to coat the inside of the tank.
I've coated with Teflon in the past and wonder if that would work???

When I use to work for a coating company I also figured out how to powder
coat fibreglass, it wasn't perfect but the parts I've done are still holding
up after 5 years.