An Icosahedron made of bevel gears.

Assembly

Text Assembly Instructions:

Some folks have had trouble following the video above (sry, it's not as clear as I'd hoped), so here are some alternate instructions. The image shows the process, working from top left to bottom right.

Image 1

• The first image above shows two large gears attached to the core, with one small gear in between them.
• Point the larger gears' pointed teeth straight up (i just took the pin out on the opposite side, so it could sit flat for the pic). These points are indicated in red in the image.
• Looking at the small gear, locate the three sides of the small triangle on the back and make sure that the insets (indicated with red “V”s in the image) are angled to accept the larger gears' pointed teeth.
• You should then be able to add the next large gear with the point up, like you see in the first image.

Image 2

• The second image shows the model flipped over 180 degrees, sitting on flat of the small gear that was just on top
• Stick on the last large gear to the pin pointed up (it can be in any orientation at first)

Image 3

• Find an empty gear slot and point it upwards.
• Orient the large gears so the points are now pointing up around the empty small gear slot, similar to their orientation in the first image.
• Pop in the small gear, with those triangle corner inset areas accepting the large gears' points

Image 4

• repeat the previous step until all of the empty small-gear slots are file

That should leave you with everything in the correct arrangement! The pins will fully seat after the initial turns, so you might hear them pop into place. If you still encounter issues, I'm active in the comments and would be happy to help troubleshoot.

Background:
I love this gear cube and it made me want to explore how to apply that approach to other platonic solids. For some stupid reason I picked the Icosahedron and the additional geometric complexity kicked my butt days. It would have probably been easier if I could math good, but that's not the case…

I still prefer how much the gear cube deforms so significantly in it's intermediate states, but the icosahedron is still a satisfying fidget. I might explore some alternative ways to break up the shape to introduce some more deformation, while retaining the smooth gearing.

Printing notes:

• If the gears begin to get loose, replacing the pins with newly printed ones will likely tighten it right up.
• To that end, printing the pins in a more friction resistant material and adding a bit of grease/lubrication can extend their life

Print profile updates (for the ones I've uploaded):
10/8/23:

• Print order changed to outer/inner/infill for better dimensional accuracy
• Brim added to pins for improved bed adhesion for most plate types
• New pins only profile, in case you still have bed adhesion issues or need a fresh set, if the originals wear out

10/22/23:

• I updated the stand-alone STL and 3mf files to include the brim and orientation tweaks from the previous update