Fuel Tank Construction

On Thu, 03 Jun 2004 15:15:54 -0700, Mark <fmc RemoveThis @sirspam.org> 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.<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: Fuel Tank Construction 

"Wayne.B" <waynebatrecdotboats.RemoveThis@hotmail.com> wrote in message
news:7rhvb0te8d89bhir4thqh49bfmva8p3nkv@4ax.com...
 > On Thu, 03 Jun 2004 15:15:54 -0700, Mark <fmc.RemoveThis@sirspam.org> 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)<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: Fuel Tank Construction 

On Thu, 3 Jun 2004 23:15:17 -0700, "Evan Gatehouse" <NONE DeleteThis @sasaf.bobo>
wrote:

 >Geometry - will you
 >duplicate the existing tanks?

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

The existing tanks are hard to see until taken out.<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: 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" <waynebatrecdotboats DeleteThis @hotmail.com> wrote in message
news:ff8tb0pcdnckjmqqkdceal6o7ne27ml89v@4ax.com...
 > 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?<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: Fuel Tank Construction 

On Sat, 5 Jun 2004 07:08:12 +0200, "Steve Lusardi"
<stevenospam.RemoveThis@lusardi.de> 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?<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: 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" <waynebatrecdotboats.RemoveThis@hotmail.com> wrote in message
news:jk63c0954i7e3cniddgke6e0bnuik7m590@4ax.com...
 > On Sat, 5 Jun 2004 07:08:12 +0200, "Steve Lusardi"
 > <stevenospam.RemoveThis@lusardi.de> 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?
 ><!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: 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" <habbi RemoveThis @islandtelecom.com> wrote in message
news:_6lwc.53670$Np3.2388048@ursa-nb00s0.nbnet.nb.ca...
 > 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" <waynebatrecdotboats RemoveThis @hotmail.com> wrote in message
 > news:jk63c0954i7e3cniddgke6e0bnuik7m590@4ax.com...
  > > On Sat, 5 Jun 2004 07:08:12 +0200, "Steve Lusardi"
  > > <stevenospam RemoveThis @lusardi.de> 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?
  > >
 >
 ><!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: Fuel Tank Construction 

On Sat, 5 Jun 2004 19:47:57 +0200, "Steve Lusardi"
<stevenospam.DeleteThis@lusardi.de> 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?<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: Fuel Tank Construction 

"Steve Lusardi" <stevenospam.DeleteThis@lusardi.de> wrote in message
news:c9rkev$6om$02$1@news.t-online.com...
 > 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)<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: 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?<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: Fuel Tank Construction 

On Sun, 06 Jun 2004 03:18:33 GMT, Jim <Jim DeleteThis @hotmail.com> 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.<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: 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: <a style='text-decoration: underline;' href="http://www.rutuonline.com" target="_blank">http://www.rutuonline.com</a>
Shameless Commercial Division: <a style='text-decoration: underline;' href="http://www.spade-anchor-us.com" target="_blank">http://www.spade-anchor-us.com</a><!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: 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" <NONE.TakeThisOut@sasaf.bobo> wrote in message
news:40c2d300_2@news.cybersurf.net...
 >
 > "Steve Lusardi" <stevenospam.TakeThisOut@lusardi.de> wrote in message
 > news:c9rkev$6om$02$1@news.t-online.com...
  > > 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)
 >
 ><!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: Fuel Tank Construction