Making a stamp die?

Not that I'd ever get:

but in the street tracker world there's a thing with fuel tanks. The aftermarket tanks are typically fiberglass and as such are susceptible to fuel damage. There are no metal street tracker tanks available, which makes me go 'hmmm'. Is there perhaps a market for such a thing?

Probably. One of the best known and most copied shapes:

These tanks are valuable, thus don't show up on the market often and are not generally modified to fit other bikes.

So in the interest of learnin' something, can anyone point me to some sort of tutorial on how to make such a beast? Keep in mind it needs to be reuseable, probably for at least a couple thousand cycles. I know this could be done Jesse James style/technique but for us great unwashed masses that's not really feasible.

You're talking about deep draw stamping which is going to require tremendous tonnage. And I would wager that the dies themselves (that tank requires more than one) would cost at least $100k if you were to farm them out to an operation which actually knows how to make them. You'll sooner do it the Jesse James way.

There's a reason all those thousands of cool sheet metal parts which we'd like to see in the aftermarket, aren't.

Yeah, it's a pretty deep draw thing. Sure it's possible for one guy to spend a week making a tank but it's just not cost effective for larger scale production, not a lot of people out there willing or able to pay thousands of $$ to have a tank made. For comparison, the 'glass tanks are usually in the $25-$300 range, they are typically hand laid in a mold.

That begs the question: where are the dies for all that Taiwan replacement sheet metal coming from? Crap, I can buy a new aftermarket bonnet/boot lid/fender for an MGB... along with just about every weird little piece of sheet metal for later model stuff. No it's not typically has high quality as the OE (just compare a Gordon to a British Motor Heritage part to see what I mean) but they seem to be able to at least get close.

By the way, some of the more popular custom tanks (such as Frisco and peanut tanks) are already made/reproduced in metal. You can even buy 'weld your own' kits.

In reply to Curmudgeon:

They are probably using original, worn out dies for those Chinese parts.

Possible. But the BMH's are made in Blighty, the Gordons in Taiwan. There's a lot of hand finishing and radius differences on the BMH stuff, that makes me think they are still using the factory dies where the Pacific Rim dies are just 'close enough' copies.

I did some Googling, there's all kinds of tutorials on how dies work but few, if any, on practical die making. I wish I could find it, there is a cool picture of a Morris Minor fender die rescued from a scrap pile which shows the rear bracing, upper and lower sections plus the punches that were built in for the bolt holes etc. You stuck your metal in, clamped it, then went 'round and hit the punches, pulled the punches back out and removed a complete fender. Of course that die cost a gazillion pounds sterling to make...

Why not coat the inside of a fiberglass tank.....

http://www.por15.com/POR-15-Fuel-Tank-Sealer_p_64.html

http://www.jpcycles.com/motorcycle-gas-tanks has steel tanks, looks mostly HD.

http://www.millerwelds.com/resources/articles/welding-gas-tanks-Ron-Covell/

Ron Covell makes it look easy.

I remember hearing when cheap import panels started coming in, mostly small patch type panels were stamped w/ hardwood die shoes. When they lost their form after so many hits they were replaced w/ fresh dies.

There's plenty of steel custom chopper tanks out there but they just are not suitable for a street tracker. Also, people have definitely coated the 'glass tanks but 'glass flexes and can crack the POR15, which is supposed to be for metal tanks only. By the way, POR15 is the only one which consistently fixes metal tanks, Kreem etc does not work! There have been reports of failure, the carbs get toasted, coated internally with fiberglass resin and now it's real pricey.

Someone out there is making plastic tracker tanks but they discolor and can't be painted.

What kind of fiberglass resin are they using? Can you get one made with epoxy instead of polyester?

Good question. I keep coming back to a steel tank for ultimate longevity since fiberglass will crack badly under vibration, though. I POR15'ed my tank and had no problems. A lot of people swear by the Caswell stuff:

http://www.caswellplating.com/restoration-aids/epoxy-gas-tank-sealer.html

But this still doesn't address the desire of many of the street tracker clan for steel tanks. Oh, well; guess it won't happen on my watch.

Curmudgeon wrote: There are no metal street tracker tanks available, which makes me go 'hmmm'. Is there perhaps a market for such a thing?

There is the meat of the matter...Is there a market that would justify the investment?

You don't so much need a tutorial on how to make the things, because that is well developed and will be farmed out to a Chinese or Indian supplier. What you need is a business plan.

Figure that for your fist order you are going to get 1000 of the things and it is going to cost you 100k. Would you go ahead with it? You can count on the second order to be about half of that, so does your market extend to the second 1000 units?

If there IS a market, you can also count on your Chinese supplier to be selling into it with parts made on your dies at half what you are selling for (they will sell for what you pay them since they already have a profit margin at that point)

We do quite a bit of sheet metal stamping where I work, and we own several large presses similar to the one in the pic I posted above.

One of the product lines I am responsible for uses a shallow drip pan; it's a brake-formed sheet metal part with welded seams. I looked into making a draw-formed version to eliminate the welding and forming labor, but the die (which was far less complicated than what that tank would require) was going to cost us $45k and the sales volume of this particular product (~600/year) wouldn't justify that expenditure.

Good info there. I'm still mulling over possible small scale stuff, please understand this is a thought exercise and as such has Really Dumb Questions (TM) to be asked.

And a thought was: get one of the 'glass tanks, use it to make a female sand mold which can then be filled with cast steel, this would form the 'outside' of the tank. Then make a male mold with basically the same technique (yes I know it's a fair amount different but bear with me) to finish the 'inside' and when I say 'finish' I mean the shape of the tank shell, always understanding there will be some body filler etc necessary on the completed tank before painting.

Finish sand etc the stamp molds for the tank shape, the base could be done in three pieces; sides, tunnel and of course the petcock holes and mounting brackets. Probably leave the mounting brackets for the final installer.

Whaddya think? Could such a thing be made accurately enough?

In reply to Curmudgeon:

There's a lot more to it than that. The draw die alone for the tank shell would weigh around 1000 lbs or more if you're doing a production run.

If you were to break the tank down into smaller "slices", would it be possible to use multiple "not deep draw" stampings, welded together, to create a tank?

Having just watched Jesse James' "Metal Church" video series on making a tank from scratch, it seems the welding is the most straightforward part of the process. You might even be able to leave that to the customer: sell a 'do it yourself' tank kit that's a handful of pre-formed metal bits. Any leaks are their problem, of course :)

fasted58 wrote: In reply to Curmudgeon: There's a lot more to it than that. The draw die alone for the tank shell would weigh around 1000 lbs or more if you're doing a production run.

I was guessing it would be around 1,000 lbs for the bottom half of the die for one half of the tank.

Wow. A thousand pounds for half of the die for a FUEL TANK? Looks like I have a lot to learn about draw dies; it seems so simple on its face...

You've got time, get a couple hammers and start beating the pieces.

McD is prolly right on that weight. Just sayin', you ain't gonna cast dies in your back yard and you gotta make the dies compatible w/ the presses as there's no GRM solution. Upper draw die gets way more complex w/ a blank holder. You may end up w/ 3-5 separate dies for draw, trim, punch, more definition etc ... just for one part. And you're prolly gonna want fixtures for fit check and weld assembly if you want a quality piece.

Not saying it can't be done. There's been an excess stamping capacity in NA, well worldwide ftm that might be willing to take on a project like that. Gonna hafta sell a E36 M3load ton of tanks to break even IMO tho.

I'd prolly go old school panel beater/ english wheel/ custom fab yur tank way.

Every time I see this thread title I think of a postage stamp being murdered

You have to figure the sell price for these. You can already buy them in aluminum and steel. took 5 mins to come up with a place that will sell one similar to that in polished alloy for $740 USD. Send him your pic and I am sure he could copy it.

send an order for 1000 and I bet you can get a sweet deal.

That's a nice piece but it isn't a Trackmaster tank which is the Holy Grail of the street tracker look, it's way too big and is more a cafe type thing.

Trackmaster:

People do them in 'glass all the time, but as mentioned 'glass has issues.

I'm sure he could come up with a bunch but $740 is a bit steep...

I would go lurk over on metalmeet forum and look up Peter Tomasini or one of the other big-dogs and contact them. If you ask for a first order of a size that was big enough to justify tooling and jigging, you might find that you get a price that you can build a business model off of.

The same thing could be done by flying over to India and proposing the same deal. India is much easier to deal with as an English speaker.

Its gonna be a ton easier, cheaper, and faster to just learn to bang out sheetmetal, that's a pretty simple shape.