CAD models of Uni Parts

Does anyone have 3d models for CAD of parts of Unicycles? I’d love it if anyone could share or sell models for hubs, bearing holders, or other rather unique parts of unicycles? I’m hoping to soon start a project of building my own unicycle. It would be especially helpful if someone had a hub model. Otherwise, does anyone know spline specs or important dimensions that I would need?


If you use an ISIS connection:




The full ISIS Drive specification (at various revisions) is available to download here:

You need to agrees to their conditions to access it, but it is free to obtain.


Thank you guys! This stuff is quite helpful!

If I was making a hub I’d probably go with the Qu-ax/KH-boundary spline rather than ISIS simply because I think it is better and it would probably be easier to machine and be a bit easier to do (since it is a parallel spline and maybe more forgiving and you clamp the crank on).

At a cursory glance it looks pretty similar to a Shimano Hollowtech-II but I haven’t looked in detail or tried interoperability between any QuAx/KH parts and Shimano stuff (I’d have to take things to bits to try). I think there was some discussion on that on here at one point.

That is probably a moot point anyway as you probably won’t find any Shimano drawings lying around, but given you probably going to buy cranks, it would probably be best to just get those, measure them and make something to fit. If you are going to make your own cranks too, it is probably still a good idea to buy ones to measure up :wink:

I’m not planning to build a hub. I was considering making cranks, though.

Fair enough, I thought you wanted to do a hub when you mentioned a hub model.

Doing an ISIS crank would be a bit of a challenge to cut the internal tapered spline. The QuAx one would be more doable – then again I don’t know what machine tools you have access to!