Featured In These YouTube Videos:

• Four in series (3.6T to one) - https://youtu.be/nvRgVUEBfp0
  • Torque testing and back-driving test - https://youtu.be/tgJUiEC9_-A
  • Three in series (2.6 Billion to 1) and gear ratio calculation - https://youtu.be/sNG63sWiV9k
  • Two In series(1.9M to 1) and explanation - https://youtu.be/VnWY0r1r9lQ

Torque Capabilities

Please know that i designed this gearbox for a demonstration model so that it would be easy for everyone to understand how a differential planetary works, for that reason i omitted the 3rd module that increases the torque capabilities.
Because of that, this gearbox cannot handle much load and it will start to skip teeth at around 3.5FT-LBS. There is more info on this in the youtube videos.

How This Works

• 1,379 Turns of the input sun gear will result in ring gear #2 making one full rotation.
  These are designed to be able to mount them in series on the channel, or drive them with the included stepper motor mount. You will need to scale the channel longer if you want to use two gearboxes and the stepper motor mount on the same channel, but keep in mind it is very boring to watch the second gearbox rotate, as it is very slow.
• This gearbox can not be back-driven, every piece of plastic on it will snap before you get the input to turn.

Gearing Information:

• The gear ratio of two of these in series is 1,901,641:1
• Three in series 2.6 Billion :1

Gears Used

Helix angle 30deg
Pressure Angle 20deg

• Planetary Gearset #1 (Input End) Tooth Module = 1

  • Sun = 16T
  • Planets = 17T
  • Ring = 50T
• Planetary Gearset #2 (Output End) Tooth Module = .846
  • Sun = 19T
  • Planets = 20T
  • Ring = 59T

Other Important Info:

CAD Files??

• I Included the Fusion 360 Project with this, But the most recent version of this project can be downloaded in lots of different formats from this link:http://a360.co/2izCe0i

• Feel free to create your own modifications and parts for this project, and if you do, make sure you create a remix and upload them, I'll link to them and possible create a collection for all of them!

Show Your Work!

• Make a "make" and show everyone what you made! (make? :0) Everyone will thank you for it!

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