I need to buy or fabricate a strong crankshaft for a strandbeest-like glass robot.

I'm making a walking robot out of glass based on Theo Jansen's strandbeest leg design. Fabricating the crankshaft has proven an odious challenge. I'm looking for a source where I can buy either a complete crankshaft to my specs or parts from which to fabricate my own. It needs to be about 30" long, with 6 crank arms (offset 120°, therefore 2 at each angle), throw on the crank to be 1". My original design was for a 1/2" diameter shaft, which is necessary if it's going to be glass, but if metal the shaft diameter could probably be smaller. The video here shows the crankshaft I made, but I don't  really trust it.http://instagram.com/p/x8xcPeyn-1/?modal=true 

The prototype leg:  http://instagram.com/p/wewqr1yn6a/?modal=true

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HdeP11 months ago

We are manufacturer of Crankshafts.We are manufactiring all of models.



whatsapp contact number:+905304229889


Where do you need it sending ? We have a full scientific glass blowing shop at work, I can always ask if one of our guys is up for a bit of a challenge. They are VERY good at what they do. Does it need to be solid, or could it be made of tube ?

bandhudunham (author)  steveastrouk2 years ago
Thanks. I'm in Arizona. I'm leaning toward another material besides glass, but if someone there wants to check out those videos attached to my question and give me a quote, I'd consider it. They ought to be able to make it out of rod, which will be stronger.

Let me have a drawing - send me a link in a PM and I'll ask.

The guys in the shop were intrigued.

Wired_Mist2 years ago

SS does souns kinda kewl >>

petercd2 years ago

Thats some serious glass skillz you got there. If you feel the glass crank is a bit dodgy, perhaps a shiny stainless steel one would do the trick without spoiling the glass look too much.

bandhudunham (author)  petercd2 years ago
Thanks. Know where I could get one made at a reasonable cost?

If you don't have a propane/mapp torch and dont fancy banging red hot metal in a vise, then probably a small engineering shop might be able to fab it up for you.

Wired_Mist2 years ago

You won't just find one, and if you do it will cost a small fortune, If it gets to your door intact... Sorry

You thought of using Poly-Carbonate? still crystal clear and much stronger! To bond it you only need a special glue that fuses it together. sounds a bit safer too lol

Hope to see what your making :D

bandhudunham (author)  Wired_Mist2 years ago

Got any clever ideas on jigging it up to keep it all straight?

Might be easiest to build a few 2-D U-shaped sections, then bond them together, offsetting each section say *90( depending on ur app)

With poly carb you will just need to heat it with a heat gun and it will bend, not sure with glass. Make a form to bend the materiel around. Then you would need to sand the junction between the two sections flat and bond them together

Poly is a great solution. I came here to say the same thing!

Kiteman2 years ago

Oh, that is a thing of true beauty!

If you're not going to go with your own glass shaft, I'd second the polycarbonate/acrylic suggestion - a decorator's heat-gun should be able to soften it so that you can bend it at specific points and then let it cool (much like, I am sure, you bend a glass rod with a small blowtorch flame).