Sunday, October 14, 2007

Building Unwheeldy

Dave Hershberger built the original Unwheeldy for as a Kinetic Sculpture Racing vehicle. In 2007 he decided to revisit the design and make something more direct. With direct drive. At some point along the way, I started helping him (along with a few other of his friends) and took some pictures, which assembled nicely into a movie:

(1:13)

Fundamentally, the wheel is a bicycle wheel. A five-cross sixty-spoke nine-foot diameter bicycle wheel wheel. The rims are aluminum tubing, bent (it takes about 1 1/2 pieces of 20' tubing for each wheel). The spokes are spoke wire, with a peened head and the other ended threaded to 56 tpi. Threading them was perhaps the riskiest part of the project, with the final solution coming into place pretty late: find a local bike shop with a Phil Wood spoke machine, having them form 1cm of thread, then using a Hozan thread chaser to form another few centimeters of threads--the small tool could not reliably start threading. Then it was a matter of building it with the previous hubs.

Frame building was more straightforward, done with a judicious combination of careful pre-planning and improvisation.

7 comments:

marouch said...

I liked so much it fell space autonomie. From Belgium

Jói said...

That is SO cool! I have a suggestion for your next project: A giant single wheel where two riders sit _inside_ the spokes! :)

Matthew Blain said...

Joi--I think a monowheel would be fun to build. Though perhaps quite difficult to ride.

See The strange story of vehicles with insufficient wheels. (And be sure to see all 5 pages from the clumsy index.)

Brion said...

hi, I am planning a school fair in late September in Santa Cruz. Do you ever bring unwheeldy to events for people to take rides on it? Let me know.

Brion

sprinsock@gmail.com

Vancouver Critical Mass Blogger said...

Wow, I've seen a few photos of this before over the years but never knew the name - this blog is great! I want to make one too! I've been experimenting with wooden wheels glued together under some tension. Far too heavy really - but requires only easier to get wood tools.

I would love to know how you made the hubs! And how did you ever calculate the correct spoke lengths? I know there are easy tools for doing that with standard size parts but this is anything but standard.

You've made a really inspiring thing here - great work! Great imagination! Bring it up to Canada sometime?

Jim Bruton said...

How did you get the spoke nipples into the curved tube rim? What was the OD & ID of the aluminum? I assume the diameter = 9'?

Very cool design.

Matthew Blain said...

Wow, sorry I don't check the comments here very often. Dave designed and milled the hubs--you can check out the original unwheeldy build blog for his build info. Spokes were calculated w/a normal spoke calc spreadsheet if I recall correctly--they're a bit longer than normal, but the math is the same. The rim has two hole drilled in it (you can see the drill process in the video), one spoke nipple diameter so it seats, the other larger so it fits through. Thread a scrap bit of spoke onto the back of a nipple and it'll go through--and turn it to both thread the nipple on the real spoke and off the tool.