Plywood fuel tanks
 

I am rebuilding a Nova Scotia lobster boat to go cruising in the Carribean.
I am thinking of building epoxy covered diesel fuel tanks. Anabody having
any experienec with those?

Thanks

Luc
MV/ Julie C
Montreal

Plywood fuel tanks
 

I believe you'll do better if you coat the inside of the tanks with
fiberglass, using the epoxy resin. Had a friend build some tanks that way
and they served quite well. Sure, the expoxy is supposed to be a good
moisture barrier itself, but the added expense of the 'glass is well worth
it.

Dick Behan



"Sir Karl" wrote in message
...
I am rebuilding a Nova Scotia lobster boat to go cruising in the Carribean.
I am thinking of building epoxy covered diesel fuel tanks. Anabody having
any experienec with those?

Thanks

Luc
MV/ Julie C
Montreal

Plywood fuel tanks
 

R.W. Behan wrote:
I believe you'll do better if you coat the inside of the tanks with
fiberglass, using the epoxy resin. Had a friend build some tanks that way
and they served quite well. Sure, the expoxy is supposed to be a good
moisture barrier itself, but the added expense of the 'glass is well worth
it.


Glass yes, epoxy no.

I believe Vinyl ester resin is the prefered choice for fule tanks.

Richard

Plywood fuel tanks
 

cavelamb himself wrote:

Glass yes, epoxy no.

I believe Vinyl ester resin is the prefered choice for fule tanks.

You believe wrong.

Lew

Plywood fuel tanks
 

Lew might have been more helpful in his answer.

Vinylester resin is preferred for fuel tanks because most fuel tanks
hold gasoline - gasoline is incompatible with most (but not all) epoxy
resins. Your tanks are diesel so you probably could use epoxy - except
that diesel increasingly laced with alcohol and even ethanol which is
usually not compatible.

Below is a link to some instructions from West - while they say you can
use West epoxy they sure don't sound enthusiastic. They also note that
fuel tanks are heavily regulated by federal law. While you can build
your own tank, if you want to sell the boat (at least in the US) you
might have an interesting legal exposure. You also may have challenges
obtaining insurance on the boat if you admit to the homebuilt tank.

http://www.westsystem.com/ewmag/18/pdf/tanks.pdf

If you do go ahead - as others have suggested use a layer or two of
cloth. Also, if the tank is over 20 gallons or so, don't forget
baffles.

Carl

Plywood fuel tanks
 

Lew might have been more helpful in his answer.

Vinylester resin is preferred for fuel tanks because most fuel tanks
hold gasoline - gasoline is incompatible with most (but not all) epoxy
resins. Your tanks are diesel so you probably could use epoxy - except
that diesel is increasingly laced with alcohol and even ethanol which
is usually not compatible with epoxy.

Below is a link to some instructions from West - while they say you can
use West epoxy they sure don't sound enthusiastic. They also note that
fuel tanks are heavily regulated by federal law. While you can build
your own tank, if you want to sell the boat (at least in the US) you
might have an interesting legal exposure. You also may have challenges
obtaining insurance on the boat if you admit to the homebuilt tank.

http://www.westsystem.com/ewmag/18/pdf/tanks.pdf

If you do go ahead - as others have suggested use a layer or two of
cloth. Also, if the tank is over 20 gallons or so, don't forget
baffles.

Carl

Plywood fuel tanks
 

Carl wrote:

Lew might have been more helpful in his answer.

You need to apply epoxy "tank resin" as the final interior coating for a
fuel tank if you expect it to survive as defined by federal CFR spec.

Laminating epoxy and knitted glass provide the strength and protection
of the plywood core.

Epoxy tank resin, a totally different epoxy product, provides not only
protection for the laminating resin, but also a non porous interior tank
surface.

Lew

Plywood fuel tanks
 

Lew Hodgett wrote:
cavelamb himself wrote:

Glass yes, epoxy no.

I believe Vinyl ester resin is the prefered choice for fule tanks.

You believe wrong.

Lew

Awright Lew,

Maybe marine gas is different from mogas these days?

I've had sevearl aircraft tanks built with epoxy fail.
But never a failure with Vinyl Ester.

Auto fuels these days have more solvents than gasoline.
And those solvents will leach through epoxy and polyester.

YMMV, but I'll stick with ve.

Richard

Plywood fuel tanks
 

cavelamb himself wrote:


Awright Lew,

Maybe marine gas is different from mogas these days?

I've had sevearl aircraft tanks built with epoxy fail.
But never a failure with Vinyl Ester.

Auto fuels these days have more solvents than gasoline.
And those solvents will leach through epoxy and polyester.

YMMV, but I'll stick with ve.

SFWIW, I don't get on boats with gasoline propulsion, so my perspective
is probably skewed.

Since this is a 40 ft boat, doubt it has gasoline propulsion, so never
gave a gasoline tank a consideration; however, were your epoxy tanks
that failed properly coated with tank resin?

It makes a major difference.

Lew

Plywood fuel tanks
 

Lew Hodgett wrote:
cavelamb himself wrote:


Awright Lew,

Maybe marine gas is different from mogas these days?

I've had sevearl aircraft tanks built with epoxy fail.
But never a failure with Vinyl Ester.

Auto fuels these days have more solvents than gasoline.
And those solvents will leach through epoxy and polyester.

YMMV, but I'll stick with ve.

SFWIW, I don't get on boats with gasoline propulsion, so my perspective
is probably skewed.

Since this is a 40 ft boat, doubt it has gasoline propulsion, so never
gave a gasoline tank a consideration; however, were your epoxy tanks
that failed properly coated with tank resin?

It makes a major difference.

Lew


Ahh, I understand now.

I'm sure it would make a difference, but I'm not sure what "tank resin"
is called when you order it.
Do you have a brand name or more specific reference?

As for the leaky gas tanks, no.
They were either AeroPoxy or Dow 330.
At least the ones I made (and replaced with VE later).

Dunno about the ones that were brought in dripping...

BTW, I do have a gasoline tank on my boat.
3 entire gallons!
Filled it up back in June and still have about a half gallon left.

That for about 200 hours sailing this summer.

Now that my girlfriend has sorta figured out the "backwardness"
of the tiller we sail out and back in more often.

I think I see a bottle of Stabil in my future.

Richard