1379:1 Compound Planetary Gearbox

thingiverse

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 This gearbox is designed for a demonstration model, making it easy to understand how a differential planetary works. I omitted the third module that increases torque capabilities, so it can't handle much load and will start skipping teeth at around 3.5FT-LBS. There's more info in the YouTube videos. How This Works 1,379 turns of the input sun gear result in ring gear #2 making one full rotation. These are designed to be mounted in series on a channel or driven with the included stepper motor mount. You'll need to scale the channel longer if you want to use two gearboxes and the stepper motor mount together. This gearbox can't be back-driven; every piece of plastic will snap before getting the input to turn. Gearing Information: The gear ratio of two in series is 1,901,641:1 Three in series is 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 are available in various formats from this link: http://a360.co/2izCe0i Feel free to create your own modifications and parts for this project. If you do, make sure to create a remix and upload them; I'll link to them and possibly create a collection of all the modifications. Show Your Work! Make a "make" and share what you made with everyone. They will thank you for it! For More Cool Projects and Upgrades, Follow Me on Thingiverse and Subscribe to my YouTube Channel Gear Down For What?