8 planets · 2.83 : 1

Eight planets fill the ring, the most the app takes, still clear of each other.

Demo sets & desk toys2.83 : 18 planetsRing held

Build it with your AI

Using the CheapCADTools connector, design a 2.83 : 1 planetary gear set in Planetary Gear Designer: module 1 mm, 20° pressure angle, herringbone teeth, a 48-tooth sun, 20-tooth planets and an 88-tooth ring, eight planets, face width 10 mm. The sun: an 8 mm bore. The carrier: a one-sided (cantilevered) carrier. The carrier's output: an 8 mm bore. Check the design, apply any Auto-fix it suggests, then export every part (the sun, a planet, the ring and the carrier) as STEP and STL and give me the download link.

Paste it into Claude, ChatGPT or any AI app with the CheapCADTools connector, and it designs this planetary set with you, checks it and hands you the files. How to connect your AI.

What's in this design

Sun

48 teeth · no shift · tip Ø51.69 mm · face 10 mm · bore Ø8 mm · no hub

Planets · 8

20 teeth · no shift · tip Ø22.71 mm · face 10 mm · bore Ø5.3 mm on a Ø5 mm pin · print 8

Ring

88 internal teeth · no shift · outside Ø103.88 mm · rim 5 mm below the roots

Carrier

cantilevered (one disc) · disc Ø88.1 × 5 mm · 8 pins Ø5 × 15.5 mm · output bore Ø8 mm

The set · Module 1 · 20° · herringbone

2.83 : 1 reduction: the ring is held, the sun is the input and the carrier the output.

Notes

Hardware: 8 × planet pin Ø5 × 15.5 mm.
Cantilevered pins: AGMA 6123 §10.7.3 keeps this to low face width to diameter ratios; retain each planet on its pin.
The Strength check rates spur sets only: helical and herringbone sets aren't rated yet.

The link opens the whole set in the Planetary Gear Designer's 3D view. Change the teeth, the number of planets or stages, which member is held, the carrier, bores or hubs, then download STL, STEP or the carrier's DXF and SVG.

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