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Train arm 64 × 14 × 5 with three Ø6 holes at 25 mm (Ferguson's paradox)

What is the arm of Ferguson's paradox? · Modern device · basis: Xem Studio design following Brown's figure (1868); true size, no printing allowance

Also called: gear train arm, planet arm, brazo del tren, Trägerarm

Exact dimensions. True size, with no printing tolerance added.

length
64.0 mm
width
14.0 mm
height
5.0 mm

Notes

  • 14 × 5 mm arm with Ø6 holes at 0, 25 and 50 mm: it turns on the fixed sun's Ø6 stud and carries the thick idler on the middle pin and the three paradox wheels on the end pin.
  • Xem Studio design following Brown's figure; true size, no printing allowance (apply your own to the mating features).

Train arm 64 × 14 × 5 with three Ø6 holes at 25 mm size chart

dimensionvalue
holes3 × Ø6 at 0 / 25 / 50 mm
section14 × 5 mm

Where the files are

Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.

Henry T. Brown (1868, public domain)Five Hundred and Seven Mechanical Movements — scan on archive.orgwebPublisher's page; dimensions are facts
507movements.comBrown's movement No. 504: figure, his text and an animationwebPublisher's page; dimensions are facts
Xem StudiodrawingwebPublisher's page; dimensions are facts

Free files

★ Free files 1 parts. Xem Studio design: free to use, print and sell things from; not to be republished as files. Xem Studio Design License. index.json

paradox-arm-25-25-b6arm, z 0..5, stud hole at the originSTEP · STL
Let your AI pull this. Add https://xemstudio.com/mcp to Claude, ChatGPT, Cursor or any MCP client (free, no account, one minute) and it can look up exact sizes, mating fits and free STEP/STL from every chat.
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Plain text: sheet.txt · JSON: /api/geometry?object=paradox-arm-25-25-b6

Train arm 64 × 14 × 5 with three Ø6 holes at 25 mm (Ferguson's paradox), isometric render of a generated part
Render of paradox-arm-25-25-b6 from the free STEP; not to scale.

Fits with

Ferguson's mechanical paradox (19 / 20 / 21 tooth wheels on one pin), isometric render of a generated part
Ferguson's mechanical paradox (19 / 20 / 21 tooth wheels on one pin)5 sizes★ 1 file

Questions

What is the arm of Ferguson's paradox?

14 × 5 mm arm with Ø6 holes at 0, 25 and 50 mm: it turns on the fixed sun's Ø6 stud and carries the thick idler on the middle pin and the three paradox wheels on the end pin.