The Counterintuitive Gear Fidget

Also check out The Counterintuitive Gear MkII with more and faster planets!

While playing with gear design again, I thought I could add a second row of planets (or are these moons?) to get some interesting behavior:

• If you lock the ring in position and rotate the sun gear, the planets rotate in the other direction around the sun.
• If you hold the sun gear steady and rotate the ring, the planets move in the same direction as the ring, but faster than the ring!

Try this little hand crank for some more fun →

Note: This model, like many print-in-place models, requires a well tuned printer-filament-combination. The tolerance settings seem to be fine for most people, but occasionally fused or too loose gears come up in the comments. I most cases that can be fixed by adjusting the flow ratio (a.k.a. extrusion multiplier). Reduce (in case of fused gears) or increase (in case of falling out gears) that value a bit.