Stainless Steel Fuel Tank

[Aussie Mike]

I'm starting on building a new Stainless fuel tank for the back of my Cobra.

I'm getting rid of the external swirl pot setup and the lift pump etc. The swirl pot will be in the tank along with a bunch of baffling.

I have a Bosch 044 pump and this will be mounted on the outside of the tank but low down so it'll have a head of fuel directly from the internal swirl pot.

This will simplify the plumbing and wiring of the whole thing and tidy up the underside of the car.

I have question for you quys. What thickness of stainless do you think I should use? I was thinking 1.6mm or 0.060" would be plenty thick enough. I might even get away with something thiner.

Cheers

[Jerry Clayton]

Mike

I use a lot of stainlesss and I like the .065in better than .049 stuff
Obviously if I'm going to the trouble of making it out of ss I want it to look nice--with the .049 I find that occasionly I will blow a weld, especially at a corner or such!!! The 065 with 1/16 rod and my welder set on a one meg pulse gives me just about perfect coordination timing with the pulse.

Hows the dragster coming?

Jerry

[mickmate]

It depends how structural you make the tank, size and whether it's baffled etc. Also depends a lot on how comfortable you are welding thin stainless. I use 18Ga for the stainless tanks I've been building. TIG welding them with a 1/16 Tungsten.

[WKB]

Mike,
The tank in the 540 I am building uses a stainless steel marine tank which is about 1mm thick. I used tin snips to cut a hole in it for the fuel pump. This tank is inside the boot with no chance of getting damaged under normal driving conditions. In a cobra it sits at the back of the car exposed to a chance of getting damaged. Aftermarket tanks made of mild steel are usually 2mm thick.
1.6mm SS would be a good choice for strength, but how heavy would it be.
Most cars, before plastic tanks, used metal tanks that would been up to 1.2mm mild steel.
A compromise between strength and weight might be to use 1.2mm SS.

Warren

[Aussie Mike]

Thanks guys.

I'm startig to lean towards 1.2mm SS

18 Guage is about 1.2mm and it will be internally braced with baffles so I reckon it should be stong enough.

I am a little concerned about welding material that thin. I'm buying a whole sheet of SS so I'll practice a heap on some offcuts till I get it down pat.

Jerry, I'll have to drop you a PM to quiz you on your welded setup. I'm still learning my way round this new AC/DC machine. My old straight DC unit was a lot simpler. I haven't got into using the pulse settings yet.

I'm still finding parts and pieces for the Dragster. There's Australia's biggest swap meet on this weekend so I'm going there cash in hand.

Everyone has pretty much talked me out of using a Quick change diff. Several stories of splitting centers and broken side bells has cured me of any desire to sit with my legs either side of one. I've been looking at a really nice Aussie made 9" housing.



http://www.crdengineering.com.au/products.asp

Cheers

[Aussie Mike]

I just found this pic while doing a search. It's 2x Bosch 044 pumps set up for an in tank installation. I reckon I'll convert my 044 external pump to single pump setup like this for the new tank.



Anyone know where to get bulkhead connectors for the Electical connections.

I also read about an electronic programable fuel level sender that some of the hot rodders have been using. It doesn't use a conventional float on a stick but has some kind of electronic sensor. Unfortunately I cant find the article. Anyone heard of it?

Cheers

[Baz]

Originally Posted by Aussie Mike

I'm starting on building a new Stainless fuel tank for the back of my Cobra.

I'm getting rid of the external swirl pot setup and the lift pump etc. The swirl pot will be in the tank along with a bunch of baffling.

I have a Bosch 044 pump and this will be mounted on the outside of the tank but low down so it'll have a head of fuel directly from the internal swirl pot.

This will simplify the plumbing and wiring of the whole thing and tidy up the underside of the car.

I have question for you quys. What thickness of stainless do you think I should use? I was thinking 1.6mm or 0.060" would be plenty thick enough. I might even get away with something thiner.

Cheers

Mike,

Neil Streeting made my tank from 3mm aluminium. In his opinion, this is the absolute minimum thickness which he would use. He stated that as the tank expands and contracts through a number of interacting factors, splits and leaks will occur on anything thinner than 3mm.

Baz

[Mando]

F--k me, thats a MOTHER of pump setup.

Regards.

[Aussie Mike]

Originally Posted by Baz

Mike,

Neil Streeting made my tank from 3mm aluminium. In his opinion, this is the absolute minimum thickness which he would use. He stated that as the tank expands and contracts through a number of interacting factors, splits and leaks will occur on anything thinner than 3mm.

Baz

If I was making it from Aluminium I reckon I'd use 3mm too. I'm planing on doing mine from Stainless which has a different modulus of elasticity and thermal expansion rates. It also has significantly higher tensile strength for its thickness.

I think a major factor in cracking is also how the tank is mounted. It needs to float independent of any chasis twisting. It also needs to be sufficiently supported as 70L of fuel can weigh a fair bit.

Cheers

[Rebel1]

Mike, here is a similar pump assy but obviously a swirl tank. You could prolly do something similar intank but with a single intank submersible 044, and of course without the pot.



This comes from: http://www.ls1.com.au/forum/showthread.php?t=79834

[AC-460]

I built my tank from 3mm aluminium If I was going to build one out of stainless I'd only use 1.2 for a sheer weight factor 1.6 would be far to heavy once finished. If it is built correctly 1.2 would be strong enough. One problem with stainless is it buckles with heat twice as bad as black steel or aluminium... You may start off with a beautiful tank before you weld it and after you weld it you think do I really want to put that buckled thing in my beautiful car... Because it will move.. The secret when you build a tank is not to weld anywhere near the bottom of the tank.. build the tank so that all the bottom corners are folded up then you only have to weld up the corners and around the top.. put 2 or three baffles inside weld securely across the bottom this stops any flexing of the bottom of the tank put the top on last and plug weld the tops of the baffles. I Tried building and internal swirl pot.... sounds good but believe its much simpler to have an external one
Cheers Mark

[Aussie Mike]

I may do it out of aluminum yet. It's certainly a lot easier to work with. Machining up flanges and stuff is much easier in ally than stainless. 3mm is easy to weld too and fairly forgiving.

I'm still making the patern for the tank so I have a bit of time to think.

Cheers

[Kanga]

g'Day Mike good to see that you are still tinkering, have you thought about using a bladder set up much like the supercars, you will only have to build a shell for it then.


steve

[Jerry Clayton]

Mike

a site you might want to look at is www.tigdepot.net
page 2 gentec 196ar-60 dual flowmeter regulator.

I run a water cooled torch on my machine with a separATE cooling machine and plumb the second argon thru the solenoid on the machine that was for water--allows me to back purge headers, tanks, etc without a hose running argon at a $$$$$rate off a second bottle

also look at the large pirex glass gas torch nozzles

Jerry

[Wazza]

Originally Posted by Jerry Clayton

Mike

a site you might want to look at is www.tigdepot.net
page 2 gentec 196ar-60 dual flowmeter regulator.

I run a water cooled torch on my machine with a separATE cooling machine and plumb the second argon thru the solenoid on the machine that was for water--allows me to back purge headers, tanks, etc without a hose running argon at a $$$$$rate off a second bottle

also look at the large pirex glass gas torch nozzles

Jerry

What ??....which ??? ....where ??....... Uh Oh.......Maybe I've had a stroke !!??

I've read this about 5 times and I have understood only a few words !

All you guys are like another species when it comes to "tech talk"....
fascinating to us mere mortals, and I wish I could speak it.

Very entertaining, and I'm sure I'll absorb SOME knowledge, if I just keep reading..........must keep reading !!!!!

anyway....back to your thread.

Cheers,
Warren

[Plums]

Mike, try Ballenger Motorsport in the US for the connectors. They seem to do most of the Delphi type connectors...

[schipps]

Originally Posted by Wazza

What ??....which ??? ....where ??....... Uh Oh.......Maybe I've had a stroke !!??

I've read this about 5 times and I have understood only a few words !

All you guys are like another species when it comes to "tech talk"....
fascinating to us mere mortals, and I wish I could speak it.

Very entertaining, and I'm sure I'll absorb SOME knowledge, if I just keep reading..........must keep reading !!!!!

anyway....back to your thread.

Cheers,
Warren

Warren,

All I can say is, if the torch is that big that it needs to be water cooled, how far does it shine? What sort of candlepower???

[Wazza]

I run a water cooled torch on my machine with a separATE cooling machine and plumb the second argon thru the solenoid on the machine that was for water--allows me to back purge headers, tanks, etc without a hose running argon at a $$$$$rate off a second bottle

That's exactly what I'm saying Schipps.....

I mean...

MY torch gets extremely hot...maybe the batteries I'm using are way too big.....water cool it you say....mmmmmm!!

AND...

I TRIED to plumb my second argon through my solenoid...but my FIRST argon got in the way.....and no matter how much I back purged AND front purged my headers....nothing worked

Enough of this silliness..... try to be serious ...PLEASE

[AC-460]

Fella's
You use a water cooled Tig torch (Hand piece) for welding aluminium but their is no need to have a water cooled Tig torch for welding 3mm more like 5mm plus...... When you are tig welding a fuel tank you purge the tank with argon gas which means you have a separate gas bottle and regulator with the hose running straight into the tank this fills the inside of the tank with argon gas while you are welding the outside. This stops oxygen attacking the weld on the inside which can cause porosity in the weld (could be a leak down the track)
Hope this helps you out
Cheers Mark

[Jerry Clayton]

Sorry I didn't realize that they didn't have watercooled torches in the southern hemispere

A water cooled torch is much smaller than an air cooled torch and lets you get in many places to weld that you can't do with an aircooled torch.

Most welders that are above the home garage size buzz boxes will have an argon gas solenoid and a second one for water flow to the torch that you can hook to a household ( or shop) waterline. They also make a self contained cooland pump/radiator that circulates a coolant mixture thru the torch and back thru a cooling coil to the tank---if using this system the second solenoid is unused----and can be attached to a second argon line to control the back purging gas---the tigdepot also sells a dual flow meter regulator that I use with doesn't then need a SECOND argon bottle/regulator