Aviation inspired aluminum tanks

[VosaME]

Hey guys,
Long before I was a member, I was one of the guys lurking in the background wishing I had a XS of my own. This sites tech resources and amazing members have been hugely inspiring, not only get my own project finally rolling, but also to encourage me to pursue my ideal career. I have been fortunate to end up in a situation this summer where I have both time and resources to finally do some product development! This is where you guys come in, I would love some input!

I work primarily as an aircraft mechanic and have been doing a lot of sheet metal fabrication work. I think a hand formed and riveted tank would look amazing, and it would be relatively easy to make custom in any style or shape. Throw in a matching tail cowl or other body panel for the full effect! Rivets could be either universal head (round button type head) or countersunk if a smooth finish is preferred. I would likely run an offset double row along most seams but could do just about anything you wanted.

These could be made from either 2024 or 6061 depending on preference and somewhere in the 0.050" thick range. 2024 I find easier to work with but it is not weldable so all fittings would be riveted. 6061 is stronger and weldable but tends to cost more, honestly either would work fine. Forming I do all with hammers and the occasional planishing hammer or rivet gun while the metal is in the soft "O"condition. Once formed they would be heat treated to T4 and then assembled with internal sealant and fittings.

I am going to be starting one for myself here soon, but wanted to see how much interest there is from the rest of the community. What do you think?

Thanks in advance!

 

[Toast]

that could be the bee's knees.

for me it would depend a ton on cost and what it looked like

 

[Ketis]

That would be pretty neat to see on one of those "raw" themed bikes.

Looking forward to seeing pics!

 

[VosaME]

that could be the bee's knees.

for me it would depend a ton on cost and what it looked like

Yes, I know that most people's concern would be cost but my initial estimates seem to indicate I could be competitive. The main difference in looks would be the visible edges where the panels came together. Other than that it could look however you wanted!

I am going to throw together some test panels later this week, I will post some pictures after that.

 

[teionjames]

Make a 3 or 3.5 gallon wassell style peanut tank. That tank has the PERFECT shape to it, it just sucks that they are 2 gallons. I think a bigger one would be incredible.

 

[Soliddrummer]

What kind of cost are we talking about? When you say "competitive", what exactly does that mean? I for one would LOVE a tank and rear fender done like this, but cost would be A1.

 

[TwoManyXS1Bs]

What kind of sealer? Ever use that stuff (can't remember name) that's used on AA5A/AA5B bottom inspection panels? Or is that old chemistry?

 

[jd750ace]

A couple of thoughts: On the alloy, have you ever worked with 5052 or 3003? They don't work harden as much as the 2024, and both are weldable. 5052 is stronger than 6061 in sheet form, polishes well, and has great corrosion resistance. 2024 has a "D" stress corrosion cracking rating and is particularly succeptable to SSC in the T4 temper. I'd be concerned about vibration, and the alcohol in our road fuels holding water on the 2024. 3003 is not a structural alloy, and is mostly used for fairings and such, but as I said, butter to work with. Most of the TV grade bike builders use it because it's like bubble gum to work with. I prefer 6061 for almost anything I make for a bike, because it is very weldable, affordable, strong, and offers great corrosion resistance when bare or polished.
We are using AMS 8802 for our fuel storage areas on the Connie, as it's rated for blue gas. Don't know if our silly road fuel additives would mess with it, but I doubt it really. Should be good.
You can't start up a thread like this without throwing up some pics on your progress. I admire your ambition to try to make something as compound as a tank with hammers, rather than a hydroform. We have 2 (!) Eckold machines in the hangar, and there's almost nothing you can't do with those things and the right jaw sets. WAAAAAAAAY beyond your typical planishing machine or shrinker-stretcher.
We'll be popping our popcorn and waiting for pics! Wish you all the luck in the world.

 

[jd750ace]

What kind of sealer? Ever use that stuff (can't remember name) that's used on AA5A/AA5B bottom inspection panels? Or is that old chemistry?

What color was it? PR1422 and AMS-8802 are by far the most common for fuel storage. PR1422 is brown and contains benign (to metal anyway) neutral metals for corrosion resistance (acts as a sacrificial layer) and AMS-8802 is just a nasty dark gray to black thixotropic polysulfide sealer. Both are actually polysulfide, just the 1422 has the corrosion inhibitors added. It is used widespread on a lot of European aircraft, for logistical simplicity, but costs 50% more than 8802, so other manufacturers save the "good stuff" for the must have it locations, primarily dissimilar metals joints, like aluminum to stainless or other steels, or magnesium to ANYTHING!

 

[VosaME]

Thanks everyone for the input, I am excited to get this rolling! I plan to be in the shop on Friday and will play around some then.

Make a 3 or 3.5 gallon wassell style peanut tank. That tank has the PERFECT shape to it, it just sucks that they are 2 gallons. I think a bigger one would be incredible.

Agreed, it has one of the classic shapes that I would love to use as a guide! As for capacity 2 gallons seems silly, I am aiming for a 3 gallon minimum on any style.

What kind of cost are we talking about? When you say "competitive", what exactly does that mean? I for one would LOVE a tank and rear fender done like this, but cost would be A1.

The material cost will be pretty low since I am buying in full sheets, honestly the most costly part is the fittings for the fuel valves and cap. If I am able to source them instead of machining in house it will be best but I am still doing research on that. Total cost I am hoping to be in the $300 range, or less. Really it just depends on how much I need to make on it to cover my time, however, since my first few are more of an experiment I hope to be able to pass them along for just the cost of materials.


jd750ace, Thanks for the input! As for the material I am not really interested in 3003 just because it is so weak. I know that a tank is not really a structural item but I want to run something that can survive a minor crash and still be functional! 5052 is very similar to 6061 but I like the characteristics of 6061 more, not to mention it is more widely used. I am hoping that cost wise it will not be much different than 2024 but still waiting on the final quote from my distributor.

I am not very worried about corrosion since I plan to seal them internally. The aviation sealer are designed for WAY more abuse than a tank on a bike would ever take, just the temperature variances alone are beyond what I need. That being said, if I can not find another sealant I am happy with I would likely use PR1422 - used it in the past, never had an issue. I am going to look into the more widely available sealer first and just work my way up the chain until I find something that can do what I want.

Hydroforming, that is damn near cheating! I wish I had access to machines like that but at this point it will be just the good old hammers. I have had success hand forming much more complex shapes out of much thicker stuff so I do not expect too many issues. If this is something that seems to be worth continuing I would just go ahead and build some forms but for now we will keep it old school

 

[TwoManyXS1Bs]

What color was it? PR1422 and AMS-8802 are by far the most common for fuel storage. PR1422 is brown and contains benign (to metal anyway) neutral metals for corrosion resistance (acts as a sacrificial layer) and AMS-8802 is just a nasty dark gray to black thixotropic polysulfide sealer. Both are actually polysulfide, just the 1422 has the corrosion inhibitors added. It is used widespread on a lot of European aircraft, for logistical simplicity, but costs 50% more than 8802, so other manufacturers save the "good stuff" for the must have it locations, primarily dissimilar metals joints, like aluminum to stainless or other steels, or magnesium to ANYTHING!

JD, I DO recall it was brown & expensive. Original Grummans used "purple passion", hi leak rate, FAA then issued AD for newer 'brown' stuff. Been over 20 years ago, don't remember p/n, paperwork/logs went with the bird. Wonderful stuff, though, applied well and stopped all leakage...

 

[jd750ace]

The purple stuff did not always cure right. We took a bunch out of the Connie that was just like fresh chewed bubble gum, and they were known as leak whores. BTW, the purple stuff used asbestos to give it it's thixotrophic properties.

 

[hotrdd]

Need some pictures. But if you are going to do some tanks what about some matching side covers?

 

[VosaME]

Need some pictures. But if you are going to do some tanks what about some matching side covers?

Yea, I plan to also do some side covers and other body panels. Would you be more interested in side covers that were a direct replacement for the originals or something that is a bit more modified?

 

[Toast]

Damn...now I'm excited! Wish I had something smart to say about materials or sealants. So would you rivet a petcock bung? Braze one in?

 

[hotrdd]

guess the real question is what could we add or do to a side cover that would make it more functional?

- More space for gears and wide rear tires?
- Oil sight glass
- temperature gauge
- mods for oil filter, hydraulic clutch or ??

 

[VosaME]

Damn...now I'm excited! Wish I had something smart to say about materials or sealants. So would you rivet a petcock bung? Braze one in?

The short answer, I am not sure yet. The petcock fitting is the easy one, even if I machine the fitting myself it is relatively easy. The cap is another story, still trying to come up with an easy solution. Do you guys have a preference of the type of cap? Would you rather use a "standard" XS flip cap or a newer flush mount type?

guess the real question is what could we add or do to a side cover that would make it more functional?

- More space for gears and wide rear tires?
- Oil sight glass
- temperature gauge
- mods for oil filter, hydraulic clutch or ??

I thought you were referring to the side covers that go over the battery box area, under the seat, but are you talking about the engine side cases? The engine side cases would be a challenge because they are cast, but I am sure I could modify them to add some additional functionality. As for the little body panels under the seat, those I am doing for sure and could easily add cutouts for just about anything. Thanks for the input!

 

[Samuraiace]

Definitely a thread I'm keeping an eye on.
I wouldn't mind seeing a modded battery/air filter side cover, something new.

 

[Toast]

Do you guys have a preference of the type of cap? Would you rather use a "standard" XS flip cap or a newer flush mount type?

As long as it is vented, I don't know if its my top priority. although an aluminum tank doesn't seem to scream flush mount to me. Bayonet style, screw style, etc, all work.

The way I figure it, is that most aftermarket tank option is going to be harley style anyways, and those parts are anywhere, so why not use it as a baseline.

 

[gggGary]

Just ran into this thread, did you ever bend metal?