Xem Studiomeasured geometry

Library › Hardware › Mechanism parts ·

Tracer arm, Ø10 hub, Ø3 pin at 15 mm

What does the tracer arm do? · Modern device · basis: Xem Studio design following Brown's figure (1868); true size, no printing allowance

Also called: tusi tracer, straight line tracer, brazo trazador, Tastarm

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

length
33.0 mm
width
18.0 mm
height
5.0 mm

Notes

  • Fixed to the planet (same Ø10 axle), it puts a Ø3 pin exactly on the planet's pitch circle (15 mm out): that point runs on a straight line through the ring's centre.
  • Xem Studio design following Brown's figure; true size, no printing allowance (apply your own to the mating features).

Tracer arm, Ø10 hub, Ø3 pin at 15 mm size chart

dimensionvalue
pin radius15 mm
hub holeØ10
pin holeØ3

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. 329: figure, his text and an animationwebPublisher's page; dimensions are facts
Xem StudiodrawingwebPublisher's page; dimensions are facts

Free files

★ Free files 1 parts. Generated by Xem Studio from the standard; threads are plain cylinders at major diameter. CC BY 4.0. index.json

tusi-tracer-arm-15tracer arm, z 0..5STEP · 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.
Set it up →

Plain text: sheet.txt · JSON: /api/geometry?object=tusi-tracer-arm-15

Tracer arm, Ø10 hub, Ø3 pin at 15 mm, isometric render of a generated part
Render of tusi-tracer-arm-15 from the free STEP; not to scale.

Fits with

Tusi couple: straight line from a gear rolling inside a ring twice its size, isometric render of a generated part
Tusi couple: straight line from a gear rolling inside a ring twice its size4 sizes★ 1 file

Questions

What does the tracer arm do?

Fixed to the planet (same Ø10 axle), it puts a Ø3 pin exactly on the planet's pitch circle (15 mm out): that point runs on a straight line through the ring's centre.