The Counterintuitive Gear fidget MkII

Bigger! More planets! Faster planets! Even more counterintuitive!

You probably have played with some planetary gears, they are cool stuff, especially those print-in-place herringbone ones. This “Counterintuitive Gear” model however has a double row of planets, which lead to some counterintuitive behavior:

normal planetary gearscounterintuitive gears

When you hold the ring and turn the sun gear,the planets move in the same direction.the planets move in the other direction.

When you hold the sun still and turn the ring, the planets move in the same direction, but slower than the ring.the planets move in the same direction, but faster than the ring.

With MkII's bigger sun gear the planets move even faster, nearly 2 rotations for one ring rotation.

The hex holes should fit regular hexagonal pencils or the hand crank (I suggest using more than one).

The MkI (with smaller sun) can be found here.

Printing

0.4mm nozzle, random seam placement, otherwise standard settings. I also used archimedean chords top&bottom infill.

This is a print-in-place model, no assembly is needed, but a well-tuned printer.

Design and description by DrJones , licensed CC-BY.