Stainless Steel gas tank.

[tauruck]

I'd like thoughts/advice on a Stainless Steel gas tank.
Why do I want to build one?.

I have the material and access to equipment capable
of doing radius bends eliminating the need for
welding on the corners.

I can't weld Aluminum and don't want to use mild steel.

I have a lot of fuel tank foam I'd like to use and I'm not sure if
baffles would be a good idea.
The tank would be 1000 x 500 x 300mm.

[wheelrdealer]

Let's see

Pros
Not concerned about the weight... check
Stainless will hold up better in the salt...check
Stainless will polish up nice and look great... check
Stainless is durable in the event of a mishap...check
I find stainless easier to tig than aluminum so for me...check
Access to sheet metal tools to do radius bends...check

Cons
A stainless is bear to drill and most fuel fillers will require 15 to 25 1/4" holes...
If you weld it you will need to back fill with argon...

For me stainless is good.
 
BR

[Peter Jack]

Mike, back purge will be absolutely mandatory. I don't know how you're set up to do it. I know some guys just put a "Y" on the outlet of the flow meter, that's what I used to do but it wastes argon and results in inaccurate flow to the weld. A while back I posted pictures of the set up I built so that back purge is only a turn of the tap away and it solves the aforementioned problems.

http://www.landracing.com/forum/index.php/topic,10731.0.html

I used two new identical flow meters because I had easy access to them but it isn't necessary to have identical units. They'll still each measure the flow accurately.

Hope this helps.

Pete

[fordboy628]

x 3 on the back purge.

 
F/B

[Rex Schimmer]

Mike,
What gauge stainless you thinking about using? Back purge is certainly required you might also try this flux, http://www.solarflux.com/Pages/Productinfo.html, which also works very well. I have used it on headers before with good success.

My real question is: Why are you building a 40 gallon fuel tank? Copious amounts of nitro??

Rex

[tauruck]

Guys thank you.

My mate Willie gave me a sheet of 304.
Same stuff as I use on the headers.

My tig set up has "T" piece that I unblock for back purging.
Not too worried about wasting some gas.

My house is set up for 220v and all the good machines
for welding Aluminum use 380v but in saying that Guido
(my welding supplier) advised that unless I'm welding
Aluminum for a living, 8 hours a day it would be a waste.
My Ally welding attempts haven't been great and I could use
his equipment but I believe in leaving the important stuff to the pros.

I just clicked with the SS. It's the best material I've welded.
Vince Roman from Burns SS really helped me a lot and I have
faith in the finished product I've done.

I know the material is tough on drill bits etc but I'll handle it.
Rex, I come from a carburetor background and according to
my turbo experts I needed at least that size tank for the 16
2200cc Bosch injectors.

I'd rather err on the side of too big than not enough and the tank
will fit the space provided perfectly.
The advice I got locally is that Ethanol corrodes Aluminum over time
and my operation as under funded as it is needs to have everything
right.

You guys always put my mind at ease and every bit of advice I've
ever gotten has been 100% on the money.

Thanks Bill, Peter, Mark and Rex.

[Sumner]

...My house is set up for 220v and all the good machines for welding Aluminum use 380v but in saying that Guido (my welding supplier) advised that unless I'm welding Aluminum for a living, 8 hours a day it would be a waste.....

There are a number of good 220v TIG welders here that will do about any job you are going to do on a race car.  I have a Miller mig and a 225 amp square wave Lincoln TIG that I love and wish I would of gotten it or one like it years earlier than I did so I'll have to disagree on Guido's advice.  If at some point you can get one do and you will say 'why didn't I do this before' like I did  ,

Sumner

[tauruck]

I hear you Sum and I would have loved a machine like that
but I do so little Ally stuff it would be wasted.

I have three welded parts on the liner so far and
Duncan did such a neat job. I'd never get to that
level. He charges me in beer so a six pack is well
worth it.

The crazy thing is that I buy all my welding equipment
from Guido and he gave me a roll of Aluminum wire for
my Mig machine.
I tried welding some flat plate and the welds were sort
of OK but not what I wanted. There was so much smoke
I decided to give the thing a miss.

A few weeks later we go to a client of his who has the same machine
as mine. Guido was setting up the system. He asks me to run a few beads
to show the guy. Perfect welds with no smoke, well very little.

I still can't figure out why I had white soot all over my helmet
when I did that test at my place.

[RidgeRunner]

     Test piece a different alloy?

     Different pre weld cleaning procedures?

     I'm not a welder, just a part time practicing wanabe looking to improve my abilities.

                                  Ed

[tauruck]

I'm going to Guido to come over and we'll do a test.
The sample I did at his client made me look good.

[wobblywalrus]

Mike, you can cut holes in stainless with a hole saw.  Machining the stuff is possible.  It takes some time to get a feel for the material.  My estimate is it takes two or three times longer to make a part from stainless as from mild steel.  Some of the stainless alloys are easier to work with than others.

You will find, that taking advantage of stainless' superior strength, it is possible to use less of it than with aluminum.  In some cases a part designed from stainless can be as light as one made from aluminum.   

[Jack Gifford]

The methanol tank (in front of passenger-side bank of pulling engine) is only .030" thick so it's very light, but quite rigid due to its shape. I cut the pattern shapes from 300-series stainless and had a professional shop expertly TIG it together. Still working well after many years.

[Peter Jack]

The trick is lots of tacks and a good back purge. Solar Flux type B painted on the back side of the material is an alternative to back purging.

Pete

[Freud]

Back purging is so useful. Requires some time and thinking

but the result is exciting.

FREUD

[tauruck]

Thanks Pete.
Freud, long time no hear!!!.

I hope you're well and keeping warm.