Fuel Tank Construction
 

If everything goes according to plan, I'm about to buy a Grand Banks
49 trawler that needs new fuel tanks (500 gallons each).

Any thoughts from this group on the best material for new tanks,
fabrication hints, and/or removal/installation suggestions?

Fuel Tank Construction
 

This can be the single biggest problem to fix - depending on the
location, access, etc. New tanks are expensive and R&R is expensive.

Proper new diesel tanks that size should be made out of 1/4 - 5/16
alum - depending on the dimensions.

What's the matter with the original tanks?

Have you really thought this through. You need several hard estimates
before you close the deal.



On Thu, 03 Jun 2004 00:03:35 -0400, Wayne.B
wrote:

If everything goes according to plan, I'm about to buy a Grand Banks
49 trawler that needs new fuel tanks (500 gallons each).

Any thoughts from this group on the best material for new tanks,
fabrication hints, and/or removal/installation suggestions?

Fuel Tank Construction
 

On Thu, 03 Jun 2004 15:15:54 -0700, Mark wrote:

Have you really thought this through. You need several hard estimates
before you close the deal.

========================================

I've gotten several estimates (all over $30K), and a large enough
survey adjustment to make for a satisfactory deal.

Have you had any tanks made from 1/4 or 5/16 aluminum? I'm
particularly looking for fabrication advice regarding coatings,
geometry, baffles, fill/vent/drain fittings, etc.

The tanks will be made by a contractor but I want to be sure they are
spec'd properly.

Fuel Tank Construction
 

"Wayne.B" wrote in message
...
On Thu, 03 Jun 2004 15:15:54 -0700, Mark wrote:

Have you really thought this through. You need several hard estimates
before you close the deal.

========================================

I've gotten several estimates (all over $30K), and a large enough
survey adjustment to make for a satisfactory deal.

Have you had any tanks made from 1/4 or 5/16 aluminum? I'm
particularly looking for fabrication advice regarding coatings,
geometry, baffles, fill/vent/drain fittings, etc.

The tanks will be made by a contractor but I want to be sure they are
spec'd properly.

I'd hire a naval architect for a day. Stuff like designing a 500 gallon
tank probably should not be left to a contractor.

Baffles will be absolutely required, about every 24-30", External
stiffeners will probably be required, depending on the head on the tank
(height from bottom of tank to top of the vent). Geometry - will you
duplicate the existing tanks?


--
Evan Gatehouse

you'll have to rewrite my email address to get to me
ceilydh AT 3web dot net
(fools the spammers)

Fuel Tank Construction
 

On Thu, 3 Jun 2004 23:15:17 -0700, "Evan Gatehouse"
wrote:

Geometry - will you
duplicate the existing tanks?

===========================

The existing tanks are hard to see until taken out.

Fuel Tank Construction
 

Wayne, you are talking about a reasonable effort and significant cost
regardless of the material chosen, Do not use aluminum, it is far too
reactive. Do not use gavanized steel. The diesel will disolve the zinc. The
ultimate material should be 316TI SS and next best would be mild steel
blasted and painted with the special Permatex tank paint. This paint is
designed for large storage tanks and must be ordered specially. I just
finished 2 water tanks slightly smaller than yours in stainless and the
material cost was $3200 and that included access hatches.
Steve

"Wayne.B" wrote in message
...
If everything goes according to plan, I'm about to buy a Grand Banks
49 trawler that needs new fuel tanks (500 gallons each).

Any thoughts from this group on the best material for new tanks,
fabrication hints, and/or removal/installation suggestions?

Fuel Tank Construction
 

On Sat, 5 Jun 2004 07:08:12 +0200, "Steve Lusardi"
wrote:
Wayne, you are talking about a reasonable effort and significant cost
regardless of the material chosen, Do not use aluminum, it is far too
reactive. Do not use gavanized steel. The diesel will disolve the zinc. The
ultimate material should be 316TI SS and next best would be mild steel
blasted and painted with the special Permatex tank paint. This paint is
designed for large storage tanks and must be ordered specially. I just
finished 2 water tanks slightly smaller than yours in stainless and the
material cost was $3200 and that included access hatches.
=============================

Steve, a couple of questions:

1. Dou you use the Permatex both inside and out? Manufacturer?

2. I've always heard that SS tanks for diesel were a problem because
of weld corrosion. Is that not a problem with 316TI?

Fuel Tank Construction
 

I was told 5052 aluminum is better than any stainless, and that stainless
tends to stress crack. I am sure there are many perfectly good stainless and
aluminum tanks out there. I would not even think about mild steel, it will
eventually start to rust.

"Wayne.B" wrote in message
...
On Sat, 5 Jun 2004 07:08:12 +0200, "Steve Lusardi"
wrote:
Wayne, you are talking about a reasonable effort and significant cost
regardless of the material chosen, Do not use aluminum, it is far too
reactive. Do not use gavanized steel. The diesel will disolve the zinc.
The
ultimate material should be 316TI SS and next best would be mild steel
blasted and painted with the special Permatex tank paint. This paint is
designed for large storage tanks and must be ordered specially. I just
finished 2 water tanks slightly smaller than yours in stainless and the
material cost was $3200 and that included access hatches.
=============================

Steve, a couple of questions:

1. Dou you use the Permatex both inside and out? Manufacturer?

2. I've always heard that SS tanks for diesel were a problem because
of weld corrosion. Is that not a problem with 316TI?

Fuel Tank Construction
 

5052 is a marine grade aluminum, but aluminum of any type is very reactive
when exposed and unprotected. I suggest that these tanks, once installed
will not offer access to all surfaces impeding inspection and maintenance.
In that light, I would not use it. 316TI is the chemical industry's material
of choice for corrosive environments. It is correct that SS will corrode
(crevise corrosion), but that takes stagnant water without oxygen and that
case will not exist is this application. If all welds are properly
passivated, inside and out, then there should be no corrosion. However by
far, the majority of diesel tanks are made very successfully of mild steel.
The success of mild steel is significantly enhanced when the INSIDE of the
tank is coated with this permatex product. This paint was developed for the
USAF for their underground jet fuel storage tanks. It is sold by the kilo
and has a 30 day shelf life. This has a very high lead content and is
hazardous to apply. Proper breathing gear is a must. It is sold to
professionals only. Another solution for these tanks would be polypropylene.
It can be welded, so custom fabrications are very possible and static
electricity and corrosion are not a problem. I believe all Chrysler vehicles
now use this. As a cost, I would estimate $3000 to $4000 per tank would be
close. Just as a side item, I use mild steel for diesel and 316TI for
drinking water.
Steve

"habbi" wrote in message
...
I was told 5052 aluminum is better than any stainless, and that stainless
tends to stress crack. I am sure there are many perfectly good stainless
and
aluminum tanks out there. I would not even think about mild steel, it will
eventually start to rust.

"Wayne.B" wrote in message
...
On Sat, 5 Jun 2004 07:08:12 +0200, "Steve Lusardi"
wrote:
Wayne, you are talking about a reasonable effort and significant cost
regardless of the material chosen, Do not use aluminum, it is far too
reactive. Do not use gavanized steel. The diesel will disolve the zinc.
The
ultimate material should be 316TI SS and next best would be mild steel
blasted and painted with the special Permatex tank paint. This paint is
designed for large storage tanks and must be ordered specially. I just
finished 2 water tanks slightly smaller than yours in stainless and the
material cost was $3200 and that included access hatches.
=============================

Steve, a couple of questions:

1. Dou you use the Permatex both inside and out? Manufacturer?

2. I've always heard that SS tanks for diesel were a problem because
of weld corrosion. Is that not a problem with 316TI?

Fuel Tank Construction
 

On Sat, 5 Jun 2004 19:47:57 +0200, "Steve Lusardi"
wrote:
As a cost, I would estimate $3000 to $4000 per tank would be
close.

Thanks for the information, estimates are close to what I've received.

The realy BIG costs are removal and re-installation - holes to be cut,
reglassed, painted, etc.

What do you use for fittings, and do you take special precautions to
isolate dis-similar metals?

Fuel Tank Construction
 

Why so all this speculation? Talk to someone who makes tanks, then
follow their advise.

I had aluminum diesel tanks made at Pipe Works, in Long Beach, Ca. They
know what they are doing.
Jim

Wayne.B wrote:

If everything goes according to plan, I'm about to buy a Grand Banks
49 trawler that needs new fuel tanks (500 gallons each).

Any thoughts from this group on the best material for new tanks,
fabrication hints, and/or removal/installation suggestions?

Fuel Tank Construction
 

On Sun, 06 Jun 2004 03:18:33 GMT, Jim wrote:

Why so all this speculation? Talk to someone who makes tanks, then
follow their advise.

=================================

There are a lot of different views and issues out there and I'd like
to get a sampling of that before making a decision. Most tank makers
will just go with what they know, not necessarily the latest thinking
or best approach. This is a big decision which will impact the future
relibility and resale value of the boat, and also involves major $$$s.

Fuel Tank Construction
 

"Steve Lusardi" wrote in message
...
Wayne, you are talking about a reasonable effort and significant cost
regardless of the material chosen, Do not use aluminum, it is far too
reactive. Do not use gavanized steel. The diesel will disolve the zinc.
The
ultimate material should be 316TI SS and next best would be mild steel
blasted and painted with the special Permatex tank paint. This paint is
designed for large storage tanks and must be ordered specially. I just
finished 2 water tanks slightly smaller than yours in stainless and the
material cost was $3200 and that included access hatches.
Steve

Commercial small / medium size vessel practice is usually aluminum or mild
steel. I don't see using plastic tanks, the size you are suggesting is
pretty big for plastic of non cylindrical shapes.

Saying aluminum is "too reactive" isn't really true. The only problem with
aluminum is if the tank is let to sit with moisture trapped against it.
Stand-offs or similar methods to keep any condensation from the skin of the
tank is a good idea.

Mild steel is generally not painted inside and the steel tanks do last at
least 20 years (the diesel on the inside tends to give a nice coating).
That said you can coat the inside of steel tanks for additional protection.

No I wouldn't use stainless steel - generally weld cracking can occur with
the thin plates of tanks. If you do go S.S., I would probably select 316L,
which is a low carbon version of 316 that is suited for welding. Much
better for corrosion than 304. But it's a pretty big price premium for
doubtful benefit.


--
Evan Gatehouse

you'll have to rewrite my email address to get to me
ceilydh AT 3web dot net
(fools the spammers)

Fuel Tank Construction
 

Wayne,
You must consider maintenance, so an access hatch will be needed for each
baffelled compartment. I use studs, nuts and make-a-gasket RTV for the seal.
The boat layout will determine where the inlet and outlet ports should be.
Here, I suggest flanges, studs and gaskets or RTV. When all assembled, test
at 2 psi for 24 hours. I take special care with dissimliar metals and if I
have to use them, I use nylon isolators and tophats around the bolts and
studs. Always check with a VOM to be sure. However, do not use these with
the fuel tank. (static). Dissimiliar metals only matter when wet. No water,
no ploblem. I would be concerned about chafe between the hull and the tank.
Either eliminate the problem by bolting hard to the hull or use rubber shock
mounts and use a bond cable across a mount for earth.
Steve

"Wayne.B" wrote in message
...
On Sat, 5 Jun 2004 19:47:57 +0200, "Steve Lusardi"
wrote:
As a cost, I would estimate $3000 to $4000 per tank would be
close.

Thanks for the information, estimates are close to what I've received.

The realy BIG costs are removal and re-installation - holes to be cut,
reglassed, painted, etc.

What do you use for fittings, and do you take special precautions to
isolate dis-similar metals?

Fuel Tank Construction
 

Evan,
You are correct, but here is the rub. Diesel is hygroscopic and with tanks
this size water, being more dense than fuel oil, will settle at the bottom
and EAT the aluminum pretty damn quick.
Steve

"Evan Gatehouse" wrote in message
...

"Steve Lusardi" wrote in message
...
Wayne, you are talking about a reasonable effort and significant cost
regardless of the material chosen, Do not use aluminum, it is far too
reactive. Do not use gavanized steel. The diesel will disolve the zinc.
The
ultimate material should be 316TI SS and next best would be mild steel
blasted and painted with the special Permatex tank paint. This paint is
designed for large storage tanks and must be ordered specially. I just
finished 2 water tanks slightly smaller than yours in stainless and the
material cost was $3200 and that included access hatches.
Steve

Commercial small / medium size vessel practice is usually aluminum or mild
steel. I don't see using plastic tanks, the size you are suggesting is
pretty big for plastic of non cylindrical shapes.

Saying aluminum is "too reactive" isn't really true. The only problem
with
aluminum is if the tank is let to sit with moisture trapped against it.
Stand-offs or similar methods to keep any condensation from the skin of
the
tank is a good idea.

Mild steel is generally not painted inside and the steel tanks do last at
least 20 years (the diesel on the inside tends to give a nice coating).
That said you can coat the inside of steel tanks for additional
protection.

No I wouldn't use stainless steel - generally weld cracking can occur with
the thin plates of tanks. If you do go S.S., I would probably select
316L,
which is a low carbon version of 316 that is suited for welding. Much
better for corrosion than 304. But it's a pretty big price premium for
doubtful benefit.


--
Evan Gatehouse

you'll have to rewrite my email address to get to me
ceilydh AT 3web dot net
(fools the spammers)

Fuel Tank Construction
 

Jim,
Think about your statement, Tanks, Long Beach, California, desert. Nothing
rusts in LA. Don't do it in Florida!
Steve
"Jim" wrote in message
ink.net...
Why so all this speculation? Talk to someone who makes tanks, then
follow their advise.

I had aluminum diesel tanks made at Pipe Works, in Long Beach, Ca. They
know what they are doing.
Jim

Wayne.B wrote:

If everything goes according to plan, I'm about to buy a Grand Banks
49 trawler that needs new fuel tanks (500 gallons each).

Any thoughts from this group on the best material for new tanks,
fabrication hints, and/or removal/installation suggestions?

Fuel Tank Construction
 

The "latest thinking" can get you in trouble more often than the tried
and true. As Evan, who has worked for some major marine architects,
said, recreational and small commercial boats almost always use aluminum
or black iron. Properly installed they will last the life of the boat.

I would not go to your local welding shop but custom tank makers like
Ezell in Florida, Aftermarket in Louisiana and Luther's Welding in Rhode
Island make hundreds of aluminum tanks a year to higher than USCG specs.
They have been building tanks for a long time and know what they are
doing.

316TI is more commonly available in Europe but considered a specialty
steel in the US. (read EXPENSIVE) The only difference between 316L and
316TI is that the TI limits carbon displacement at high temperatures.
That maintains the corrosion resistance better in the welds but does not
prevent stress cracking. 316TI is specified for applications where the
temperatures regularly exceeds 800F. If your tank ever gets that hot
you have a lot more to worry about than stress cracking.

A 500 gallon tank is WAY to big to be built in welded or even rotomolded
poly. Once you get larger than about 70 gallons they are almost always
cylindrical. Above about 250 gallons they are vertical cylinders like
farm storage tanks.

Wayne.B wrote:

There are a lot of different views and issues out there and I'd like
to get a sampling of that before making a decision. Most tank makers
will just go with what they know, not necessarily the latest thinking
or best approach. This is a big decision which will impact the future
relibility and resale value of the boat, and also involves major $$$s.


--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

Fuel Tank Construction
 

On Sunday 06 June 2004 11:51 am in rec.boats.building Steve Lusardi wrote:

Wayne,
You must consider maintenance, so an access hatch will be needed for each
baffelled compartment. I use studs, nuts and make-a-gasket RTV for the
seal. The boat layout will determine where the inlet and outlet ports
should be. Here, I suggest flanges, studs and gaskets or RTV. When all
assembled, test at 2 psi for 24 hours. I take special care with dissimliar
metals and if I have to use them, I use nylon isolators and tophats around
the bolts and studs. Always check with a VOM to be sure. However, do not
use these with the fuel tank. (static). Dissimiliar metals only matter
when wet. No water, no ploblem. I would be concerned about chafe between
the hull and the tank. Either eliminate the problem by bolting hard to the
hull or use rubber shock mounts and use a bond cable across a mount for
earth. Steve

All good stuff, but one additional point :=
Each tank should have a bottom drain at the lowest point. Water
contamination is a common problem for most fuels, especially diesel.
Water will always settle to the bottom of the tank, it is a good idea
to wait overnight after refueling to allow any water to separate and
then drain the tank bottom until clean fuel comes out.
It is also good practice to also do this as a regular routine inspection
to prevent the buildup of condensation or inward leakage from vents and
fillers.

--
My real address is crn (at) netunix (dot) com
WARNING all messages containing attachments or html will be silently
deleted. Send only plain text.

Fuel Tank Construction
 

Glenn is correct, there are many people that make fuel and even water tanks
in Alu, but we all have predjudices and personnel favorites. Personnally, I
make diesel tanks in mild steel, Water tanks in 316TI. Yes, in Europe 316TI
is the same price as 316L. The major use in Europe of TI is not high
temperature applications, it is food processing vats, because it resists
acids better than L . I believe that most high temperature applications use
inconel, not 316. But be that as it may, this thread has exposed all the
available solutions and pitfalls for the audiance and that is what this NG
is all about.
Steve

"Glenn Ashmore" wrote in message
news:tVCwc.23786$My6.15959@fed1read05...
The "latest thinking" can get you in trouble more often than the tried
and true. As Evan, who has worked for some major marine architects,
said, recreational and small commercial boats almost always use aluminum
or black iron. Properly installed they will last the life of the boat.

I would not go to your local welding shop but custom tank makers like
Ezell in Florida, Aftermarket in Louisiana and Luther's Welding in Rhode
Island make hundreds of aluminum tanks a year to higher than USCG specs.
They have been building tanks for a long time and know what they are
doing.

316TI is more commonly available in Europe but considered a specialty
steel in the US. (read EXPENSIVE) The only difference between 316L and
316TI is that the TI limits carbon displacement at high temperatures.
That maintains the corrosion resistance better in the welds but does not
prevent stress cracking. 316TI is specified for applications where the
temperatures regularly exceeds 800F. If your tank ever gets that hot
you have a lot more to worry about than stress cracking.

A 500 gallon tank is WAY to big to be built in welded or even rotomolded
poly. Once you get larger than about 70 gallons they are almost always
cylindrical. Above about 250 gallons they are vertical cylinders like
farm storage tanks.

Wayne.B wrote:

There are a lot of different views and issues out there and I'd like
to get a sampling of that before making a decision. Most tank makers
will just go with what they know, not necessarily the latest thinking
or best approach. This is a big decision which will impact the future
relibility and resale value of the boat, and also involves major $$$s.


--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

Fuel Tank Construction
 

The concept I'm advocating is following the advise of experienced tank
makers who know how to build to specifications and standards. And stand
behind their work.

I'm not advocating any specific material. I'd talk to a half dozen
builders with experience and see if they agree on material and
construction. (They do, by the way).

Jim

Steve Lusardi wrote:
Jim,
Think about your statement, Tanks, Long Beach, California, desert. Nothing
rusts in LA. Don't do it in Florida!
Steve
"Jim" wrote in message
ink.net...

Why so all this speculation? Talk to someone who makes tanks, then
follow their advise.

I had aluminum diesel tanks made at Pipe Works, in Long Beach, Ca. They
know what they are doing.
Jim

Wayne.B wrote:


If everything goes according to plan, I'm about to buy a Grand Banks
49 trawler that needs new fuel tanks (500 gallons each).

Any thoughts from this group on the best material for new tanks,
fabrication hints, and/or removal/installation suggestions?

Fuel Tank Construction
 

Apparently you don't live in LA - everything along the coast rusts
like crazy - think about it - Long Beach is not desert - it's a marine
climate - salty foggy etc.

On Sun, 6 Jun 2004 12:57:57 +0200, "Steve Lusardi"
wrote:

Jim,
Think about your statement, Tanks, Long Beach, California, desert. Nothing
rusts in LA. Don't do it in Florida!
Steve
"Jim" wrote in message
link.net...
Why so all this speculation? Talk to someone who makes tanks, then
follow their advise.

I had aluminum diesel tanks made at Pipe Works, in Long Beach, Ca. They
know what they are doing.
Jim

Wayne.B wrote:

If everything goes according to plan, I'm about to buy a Grand Banks
49 trawler that needs new fuel tanks (500 gallons each).

Any thoughts from this group on the best material for new tanks,
fabrication hints, and/or removal/installation suggestions?

Fuel Tank Construction
 

On Thu, 03 Jun 2004 00:03:35 -0400, Wayne.B
wrote:

If everything goes according to plan, I'm about to buy a Grand Banks
49 trawler that needs new fuel tanks (500 gallons each).

Any thoughts from this group on the best material for new tanks,
fabrication hints, and/or removal/installation suggestions?

The small light Cessna products of the last 50 years use aluminum
fuel tanks. Those tanks don't leak. Some bigger airplanes carry
internal fuel tank bladders. Those DO leak, after a while.
My rain gutters, possibly yours too, are either aluminum or vinyl.
(USA practice)

After my neighbor's not-so-handiman cut down an overhanging
tree onto my gutters, I replaced several. I was interested to see
what water had done to the inner unprotected aluminum surface.

In general they were clear - though I saw several small patches of
black corrosion, where possibly some leaf had sat for a good while

Brian W

Fuel Tank Construction
 

"Wayne.B" wrote
I've gotten several estimates (all over $30K), and a large enough
survey adjustment to make for a satisfactory deal....
The tanks will be made by a contractor but I want to be sure they are
spec'd properly.


Evan Gatehouse wrote:
I'd hire a naval architect for a day. Stuff like designing a 500 gallon
tank probably should not be left to a contractor.

Agree strongly! While I hesitate to suggest that it *must* be an
adversarial relationship, you really don't want the low-bid contractor
doing both the design and construction. If you're going to drop that
much money, you should spend the small amount extra to get a proper
design for the tanks.

Also I am slightly surprised that nobody suggested Monel... if it's
going to cost that much anyway...

Fresh Breezes- Doug King