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Mathius
01-28-2007, 10:04 AM
Anyone fabbing their own stainless gas tank? What are you using for the filler lip, and for the place where the fuel sender goes. I can fab the tank fairly easily and weld it up, but I don't know about those parts.

Does anyone sell these parts for weld-in?

I thought about just reusing those parts off the stock tank, it IS possible to bond stainless to regular steel using the correct alloy wire (I'd have to look it up, but I think E308 stainless works best). But then I'd loose the corrosion benefits of having the stainless tank.


Mathius

Rick D
01-28-2007, 03:05 PM
Just build it out of steel than have it powder coated. Than you can use your old parts from your old tank.

Mathius
01-28-2007, 06:13 PM
Just build it out of steel than have it powder coated. Than you can use your old parts from your old tank.

Well, like I said, I'd loose the corrosion benefits of using stainless. Powdercoat would help, but a gas tank can still rust from the inside out, and you can't powdercoat the inside. Could seal it I suppose, but that's never easy to tell how well it coated.

Also, another concern is cutting up the old tank because it'll be a very touchy thing to make sure all the gas fumes are out of it.

Mathius

parsonsj
01-28-2007, 06:51 PM
I've made tanks in stainless and aluminum.

I used aftermarket sending units (Auto Meter), and standard race style filler openings.

jp

Mathius
01-29-2007, 03:17 PM
I've made tanks in stainless and aluminum.

I used aftermarket sending units (Auto Meter), and standard race style filler openings.

jp

John, do you know if the autometer sending unit will hook up to a stock gauge? Not sure what I'm doing with the dash yet.

Also, what do you mean by racing style filler openings? Can you post a link?

Thanks,
Mathius

parsonsj
01-29-2007, 04:08 PM
Yes, AutoMeter sending units will work with most factory gauges. Their tech support can get you set up.

Try http://store.summitracing.com/partdetail.asp?autofilter=1&part=RCI%2D7034A&N=700+115&autoview=sku

jp

Camaro Zach
01-29-2007, 05:26 PM
I used one of these on my last fuel cell. http://store.summitracing.com/partdetail.asp?autofilter=1&part=RCI%2D7036A&N=700+115&autoview=sku
But if your building a tank to go in the stock location you can just weld on a piece of stainless tubing and run a gasoline safe hose.
Any of the 0-90 ohm AutoMeter sending units will be compatible with your GM gauges. (if that is what you have)

taylorl572
01-29-2007, 07:36 PM
a good stainless to mild rod is 309.

Bow Tie 67
02-01-2007, 03:50 PM
What recommendations on gauge for stainless and aluminum and grade.

Mathius
02-01-2007, 05:56 PM
What recommendations on gauge for stainless and aluminum and grade.

18 gauge is probably ok for stainless I'm guessing, 16 would be better.

I'm guessing aluminum should be somewhere in the 12-14 range.

Mathius

Camaro Zach
02-01-2007, 06:26 PM
Stainless I wouldnt do anything under 16 ga. (.0625) 304

The last aluminum cell I built was 11ga (.090) 3003

cm-67
02-01-2007, 06:53 PM
I also plan on fabbing my own fuel tank. Mine will go in the stock location. It will be an internal baffle design with a sump in the bottom of it. I planned on ordering a sending unit from Jegs or Summit, but have yet to do so. Mine will be made of 16 ga. 304ss. I work at a sheetmetal fab shop, so all I have to do is take some final measurements and go to work. I figure about a week worth of lunchbreaks and I'll be good to go.

309L is the proper rod for welding stainless to carbon steel, Other types can be used but you run the risk of the weld cracking. If you use stainless I would rec. using 308 filler rod, don't just fuse it like a popular manufacturer does. It may work but adding filler rod makes for a much stronger weld, and a fuel tank is not an area I am willing to take a risk.

Chris

parsonsj
02-01-2007, 07:11 PM
My aluminum tanks are made with .060 5052 but with tubular frames. My stainless tanks are 18g (.049) but with load-bearing baffling.

jp

Bow Tie 67
02-01-2007, 08:16 PM
Thanks for all the help guys. JP do you know how heavy your aluminum tank was when completed?

parsonsj
02-01-2007, 08:35 PM
JP do you know how heavy your aluminum tank was when completed?No, other than to say it was pretty light, which means nothing. It's got 15 gallons of 93 octane in it right now, so it's a bit heavier now. :)

jp

cm-67
02-03-2007, 07:35 PM
parsonsj,
Not trying to hijack, but I am looking for some ideas on the baffling you do. I have a pretty good idea of what I think it should look like, but would appreciate some design input. Also the sump. I probably will use an external electric fuel pump, so I believe this is the way to go
Chris

cm-67
02-03-2007, 07:44 PM
18ga ss weighs 2.1lbs per sq ft
16ga ss weighs 2.625lbs per sq ft
can't find my aluminum chart but if memory serves correctly I think it is 60% of the weight of ss
My personal opinion, if I were to use al. I would use .090
Chris

parsonsj
02-03-2007, 08:19 PM
I am looking for some ideas on the baffling you doHave a look here: http://www.iimuchfabrication.com/Tanks/

Hope it's useful.

jp

LMDGUY
02-04-2007, 07:39 AM
Have a look here: http://www.iimuchfabrication.com/Tanks/

Hope it's useful.

jp

:hail:


WOW!!! that looks sweet. I will need something like hat for my falcon

Mathius
02-04-2007, 08:25 AM
John,

That link was very inspiring and should be helpful when I get to my own project. The only thing I want to do different is I don't want the filler in the trunk. But you seem to have a full firewall in yours. Is your car still streetable?

The smaller plate near the filler neck is the aftermarket fuel sender you were talking about, yes? Did it rivet in place?

Mathius

parsonsj
02-04-2007, 08:30 AM
Mathius,

Yes, I drive my car on the street all the time. In fact, that's the only place I have driven it. It's tagged, titled, and insured here in Florida.

Correct about the fuel sender. It bolts in place. I welded a .25" aluminum plate to the underside of the sheet, then drilled and tapped it.

jp

Mathius
03-17-2007, 04:50 PM
John,

Recently my buddy bought a good sized mig welder with a spool gun. I realize TIG is the weapon of choice for aluminum, but I thought I might try an aluminum fuel tank if I can get some measurements off my current stock tank.

How did you fabricate the fittings on your aluminum tank? Did you thread the aluminum?

My concern is that aluminum threads are a bit soft and I don't want the threads to gaul, or leak.

Mathius

80proZ
03-21-2007, 05:54 PM
I'm not sure i would use a spool gun for a gas tank.Unless you really know how to weld with one, they can be very inconsistant,especially on thinner materials.I would surely recommend you TIG it.

parsonsj
03-22-2007, 07:57 AM
Mathius,

I've never used a spool gun (or MIG-welded aluminum in any way), so I can't comment. I don't know.

For fittings, I bought weld-on AN bungs. I used male bungs, but would probably use female next time. I think they would be easier to weld in place.

jp

Mathius
03-22-2007, 12:37 PM
I'm not sure i would use a spool gun for a gas tank.Unless you really know how to weld with one, they can be very inconsistant,especially on thinner materials.I would surely recommend you TIG it.

Well I can't afford a TIG welder, and I didn't spend all kinds of money on school to learn how to weld to be afraid of it.

There's nothing magical about a TIG welder, it doesn't make a better weld. It just gives you a lot more control.

As long as I pressure test it, it should be fine, and I'll be able to see if I got penetration inside and out until I weld on the last panel so... Not a big deal.

Mathius

toxicz28
03-22-2007, 04:39 PM
I would surely recommend you TIG it.

Oh boy! Here we go again.

69stang
11-06-2007, 06:49 PM
Have a look here: http://www.iimuchfabrication.com/Tanks/

Hope it's useful.

jp

About 3 years ago I stumbled across your page for fabricating your fuel tank. I bookmarked the page and then a short time later lost the bookmark in a hard drive crash. I've been searching since for your page and couldn't remember where I linked from. I stumbled onto this forum today linked from a thread on stangnet. I'm into fabricating what I can and was browsing this section of the forums and can't believe I stumbled into it again. How strange is that?

parsonsj
11-06-2007, 07:03 PM
Way cool. And for an even stranger twist, I used to live in Dayton.

Glad you find it useful.

jp

Mathius
11-22-2007, 07:07 AM
John. You guys have any suggestions on mounting one? I don't want it IN the trunk like yours, I'm thinking I want to keep it in the stock location.

If I use the stock mounting straps I would probably have to make channels for the straps so there was no risk of the tank moving side to side, and that's extra fabrication.

I thought about just putting mounting tabs and mounting it above some bracing (square tubing, angle, c channel, etc. mounted to the frame) but that would almost certainly involve running bolts that I'd have to reach up over the tank and frame to bolt in place. I'm not sure how easy that would be. When I fab something, I like to make it as easy as possible to function and install.

There are obviously ways to do this. I'm looking for the easiest possible suggestions.

Mathius

69stang
11-22-2007, 04:09 PM
You could weld nuts to your framing. Then bolt your straps in place. Or reverse it with bolts welded in place.

gt1guy
11-23-2007, 01:58 PM
Or, you could just bead roll some channels into the tank itself. Don't forget to put rubber between the tank and the straps.

Kevin

CRead01
11-24-2007, 05:33 AM
this is an excelent thread. I have had some of the same questions brewing in my head. alot of great info.

Mathius
11-24-2007, 09:48 AM
Or, you could just bead roll some channels into the tank itself. Don't forget to put rubber between the tank and the straps.

Kevin

I don't have a bead roller, that's why I'm trying to avoid the extra fabrication. The rubber idea seems ok. Probably harder to position everything when mounting. Would have to have a friend help I think.

Any idea where you can just purchase a sheet of rubber though? I have a tool box I need to mount in the bed of my truck and I don't want to mess up my bed rails, so I'm looking for rubber for that application as well.

Welding nuts or bolts to the frame is ok I guess. It's just that if something happens to the threads, I'd have to cut them out and fabricate something new. I live in the rust belt. But I may have to go that way anyhow.

Mathius

parsonsj
11-24-2007, 10:23 AM
You might consider rivet-nuts (an easy way to put threads into sheetmetal). Have a look at McMaster-Carr (http://www.mcmaster.com). They've got a complete selection, and you can find rubber sheets there too.
jp

rb70383
12-28-2007, 06:49 PM
Do home made tanks have to be certified? I read some where abpout a series of tests a tank has to go through. ???

parsonsj
12-28-2007, 08:59 PM
Certified? For what? I'm sure a racing body has to have some certification. For street use ... whatever your local state requires for registration.

jp

rb70383
12-29-2007, 05:54 PM
I remember reading that a tank has to be filled to capacity and dropped from a certain distance and not leak or not leak more than a specified amount. I honestly cant remeber where i read that. I'm thinking of making trying my skill at making an aux tank for my truck and I have heard that "test" mentioned before by different people. :hmm: I like how you did the tube structure and will be doing the same idea. I'm in tampa, so what ever Fl needs.

rb70383
12-29-2007, 06:01 PM
Found it:

(e)(1) Drop test —
(e)(1)(i) Procedure. Fill the tank with a quantity of water having a weight equal to the weight of the maximum fuel load of the tank and drop the tank 30 feet onto an unyielding surface so that it lands squarely on one corner.
(e)(1)(ii) Required performance. Neither the tank nor any fitting may leak more than a total of 1 ounce by weight of water per minute.

http://www.fmcsa.dot.gov/rules-regulations/administration/fmcsr/fmcsrruletext.asp?section=393.67

However after skimming it, it seems that it only applies to commercial vehicles. So we should be in the clear.