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got the R90 out in the sun

Out-Standing! I think yer holding back on us; that looks like you've been doing this for a while. But no cookies for you until you replace that tray. Come to think of it, cookie sheets might be cheaper than a sheet of Al.

I've bought some stuff from TM Technologies in the past. They have great on-line tutorials. Here's one on annealing aluminum that should come in handy > http://www.tinmantech.com/html/aluminum_alloys_continued.php
 
I'm still wondering how all this is going to work out. I watch what they do on American Chopper with the welding, pounding, forming of sheet metal to form a tank. Maybe in the end the details get lost on TV and/or is covered in paint. But it would sure seem difficult to get the metal smooth enough so that the appearance/paint didn't amplify all the undulations in the metal.
 
A little rough is historically accurate. . .

I agree with Kurt about how difficult it might be to get it absolutely smooth. That said, take a look at some of the old pix of those "dustbin" racing fairings of yore -- obviously one-off, and YES! obviously done by human hands! (Sadly, some dustbin fairings were prone to causing the bike to take to the dirt in sidewinds, but not because they were handmade.)

Watch out for cookie crumbs in the tank --

Brother, you've got a "set" to take this project on, and GOOD ON YOU!

FYI, the excellent book, Shopcraft as Soulcraft addresses the current lack of shop classes in schools. When I grew up in Arkansas (one of the poorest states) during the 60's, our high school had BIG woodworking and metal shops with plenty of machine tools to play with. Wonder how many guys got a CAREER out of what they learned in shop class? Lots, is my guess.

Walking Eagle
 
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898 I'm curious as to how your "carpet/planisher shrinker/stretcher combo" works. It's a "pounding" operation, right?

The "bag-of-walnuts" finish is usually removed by rolling the material with an "English Wheel". Harbor Freight offers one, it's on sale this week for $299

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When I grew up in Arkansas (one of the poorest states) during the 60's, our high school had BIG woodworking and metal shops with plenty of machine tools to play with.

Ditto in southern Indiana at the time. We started "shop" in the seventh grade; drafting, woodworking, metal smithing, leather work, and foundry. I still have the center punch I turned, and the cast aluminum bookends I made. AS I recall, we had to draft the metal part we were going to make, and then used the drawing to make the part (including holding the tolerances). A few years ago Pacific Gas & Electric offered a four year "technical apprenticeship" (paid) through the local community college and out at it's Diablo Canyon Nuclear Power Plant - only two students were interested enough to even show up at the orientation, and the program was canceled. The two students were hired on the spot due to their incentive.
 
Went with .063, which is really hard to pound.

The more you pound it the harder the metal gets (called work-hardening). That's what the "annealing" process does; returns the metal to a soft(er) state. It's an ongoing process; pound a bit, re-anneal, pound some more, re-anneal.

There's a trick to annealing aluminum in that link ... using torch soot to coat the metal, and then heating the sheet until the soot burns off. There's a sweet-spot though; too hot and you have a puddle of aluminum. Read the link.

Now beat it kid!
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so I know that I am new here, but there is a reason my knickname is beater

i am a metal artist in my spare time, and I am watching this with interest.

my only advice is anneal, anneal, anneal.

Hit me offline if you get stuck.

johnny
 
This is where that part came from, a surplus piece, maybe a Quartermaster can tell what it originally was. I was going to close up the hole with a plate, but then it wouldn't have the original design feature of having a bulge on top of motor?

That is a hand splint. I was a medic for years and saw those things all the time.
 
The Project. . .

(1) NOT too much detail.

(2) When SWMBO suggests that I'm crazy, I can now point to this thread, and say, "No, honey, HE'S utterly demented."

(3) I think I heard the R90S ask, as it watched the proceedings, "WTF is he doing?"

Keep on - this is really, really amazing stuff.

Walking Eagle
 
You know what you could do...

Hollow out the wood tank & put an aluminum one inside. Wouldn't that jack with people's ideals... :bottle
 
Seriously? 12ga? wow. you're a stud. 16ga would have been fine man, but hey, they're your arms.. lol

what type of al are you trying to work with? 6061? 7005? aluminum has a pretty narrow range to work with before it gets too brittle.

j
 
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sorry - I misunderstood. I thought I saw that you were using 12ga (.080). 16ga is still overkill, and yes, the strength will come from having the finished shape. The trick will be to make sure you are evenly planished to make sure that you have aligned all the grain and gotten the material as uniform as possible.

I know you're not there yet, but when it comes to welding on the tabs, remember that that this will be the weakest point of the structure from a vibration and cracking perspective. You will most likely need to form a "dissapation zone" on the mount areas. meaning, slightly thicker stock welding over the tabbed area, (usually 2-3 times the tab surface) to have the tab attached to that, then the plate to the material.

I am sure you will source a quality welder, but make sure that you discuss heat treatment of the base material around the welded zones "if" they are in load baring areas.

Do you have a stick or basic mig? I could show you how to make some basic tucking tools that will save you a ton of time if you do, out of drum brake tools. my other recommendation is to get a bag and hammer assortment for plannishing and forming, simple but effective.

I'll go back to my hole now. Oh, and not only is steel "real", but it's easier too! lol

j



I'm using 63 thousanths, or about a 16th of and inch. Next jump up was 80 thou, and that stuff was thick. 3003 grade. Could'a went with a 5000 grade, more corrosion resistant marine grade, but couldn't see the upside. 3000 grade is pretty malleable. Don't know anything really about doing this. Never done it before. The grades of aluminum start at 1000 and go on up to 7000, each with its own characteristics and applications. Cyclists know a lot about these things. My partner thinks it's crazy and will blow up?, and it's illegal. I said I'll git a fire extinguisher when I go riding. Not sure the tensil strength of the steel tank is much more. Or, we could just sit in a rest home watching TV? This is hard, don't know if it can be done, don't recommend it.
 
Yes, from a totally rational point of view, it might make more sense to buy a tank.

I've completed a bunch of projects that ended up costing more because I did it myself, but the satisfaction is worth every penny (in most cases).

I've really been enjoying watching this project.

Barron
 
Looking at McMaster-Carr's site, 0.063" thick 3003 aluminum in a 24x36" sheet is $33.22. It seems a lot of mistakes and rework is possible considering the cost of materials. For me, this would be an opportunity to practice and improve my mig (GMAW) welding aluminum skills. In for a penny, in for a pound. But, that is me.

FWIW, I have about four (or six?) books on sheet metal work and (eventually) intend to make some items. Your tank tank is a challenging item, but it looks like you have a good approach. From what I have read (all book learning), a rawhide mallot is a very useful tool for sheet metal forming.

The home build aircraft types have some online information about aluminum sheetmetal forming along with the tinmantech.com website (which seems mostly about welding). There is also a metalshapers.org website, but I have not found that especially useful. However, you may. A decent torch to anneal the aluminum after working and figuring out the annealing technique is also useful. I will be following your project with interest. Good luck!
 
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We had a visitor in my welding class the other day--a local fabricator who makes Moon-style tanks for vintage Top Fuel dragsters. He gas welds the tanks, which the sanctioning body prefers, as the weld area is more ductile and less likely to rupture in the event of an actual emergency.

He says the key to it is the right filter in the welding goggles. The right filter will show a color change in the flux at the right puddle temperature, apparently.

Not being an advanced enough welder myself, I did not inquire further. But I do want to try making a tank someday to go with my Blinged-out (alu parts) Airhead.
 
898, I'm really curious.... are you "annealing" this material as you work it? It really improves the form-ability of all metals, but especially aluminum.

Put some of your "scrap" to work and give it a try.... it will take a bit of experimentation (which you obviously love) and I think you'll be pleasantly surprised.

Here's that link again > http://www.tinmantech.com/html/aluminum_alloys_continued.php
 
... then you got the problem of holding onto the hot piece. Just pounding does away with the torch,

Let the piece cool before you wail on it... .. it doesn't need to be hot when you work it. Annealing "softens" the metal so you can form it more easily.... I think you owe it to yourself to try this 898... it really is the "trick" to panel forming. And it will allow you to realize what's in your head (concept wise) without fighting the material. It's a lot more gratifying, not to mention encouraging, when sh*t starts to work the way you thought it would.... Just sayin'.

Torch in the garage...? Same as working with sharp tools. Just be careful... . .
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Annealing is the hot ticket (pun intended).... it REALLY makes the process work. Again, it's akin to working wood with sharp tools.
 
"Annealing" is technically "heat treating". You are using heat to change the molecular structure of the aluminum; in this case, it's ductility (softness). It's generally at a lower temperature; aluminum anneals around 75-775??F. Also note that the whole sheet does not need to be raised to a uniform temperature simultaneously, it can be done in small sections.

"Heat treating" as referred to in the (3003 material spec) means that the material can not be significantly hardened/strengthened, or the chemical make up of the material changed, by elevating it's temperature to an extreme degree. Other aluminum alloys can be altered (i.e. like for aircraft landing gear forgings (2000, 5000, 6000, 7000, 8000 series alloys))

3003 hardens as it is formed, and needs to be frequently annealed to "re-soften" it so that it can be formed. If you don't the material only becomes harder and more brittle ... prolly not so good for a motorcycle tank.

Found this on YT; another technique, more predictable than using the soot method; coincidentally, the material in the video is 3003.

<iframe width="420" height="315" src="http://www.youtube.com/embed/QPe6rBPOnx0" frameborder="0" allowfullscreen></iframe>

Tempilstik temperature indicating sticks. You can probably find them at your local welding supply outlet. They're available on eBay too. $5-7

<iframe width="560" height="315" src="http://www.youtube.com/embed/WIMqVIM39I0" frameborder="0" allowfullscreen></iframe>
 
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