Mini Planetary Gear Print-in-Place Demo This is a mini version of the original Planetary Gear Print-in-Place Demonstration unit I made previously. I really liked the original version so I thought I would make a lower profile version about the same weight as a benchy so it could be used as a test print or for filament color samples. This version is only 19g about a third of the original size.

Size The gears are module 1, both the sun and planet gears have 12 teeth and the ring gear has 36 teeth. Ratio: 3:1 or 1:4

Demonstration If you hold the carrier and turn the sun gear, you get at 3:1 speed reduction. This ratio is a result of the 36 teeth on the ring gear divided by the 12 teeth on planet gears. If you wanted further reduction, you would make the sun gear smaller than the plant gears.

If you hold the carrier and turn the ring gear, you get a 1:4 speed increase on the sun gear. The is because the much larger diameter ring gear is moving faster than the smaller sun gear. The equation works out to be the 36 teeth of the ring gear divided by the 12 teeth of the planet gear plus 1.

If you hold the sun gear and spin the ring gear and the carrier, there is no reduction and it acts like a bearing

Print instructions Designed for a .4mm nozzle, .2mm layer heights, no supports at 100%. This version has tighter clearances than the original so it will work better at a smaller scale. It is a little more difficult to print so verify your; first layer height, extruder calibration, and the size of layer change blobs.

Printed with Protoposta’s Mermaid's Tale Metallic Teal HTPLA(aff.)

Printed on the Muldex rep-rap IDEX printer.

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