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Spur gear, module 1, 30 T, 26 mm face (thick idler), Ø6 bore, tips at Ø31.5

What is a thick idler gear for? · Modern device · basis: Xem Studio design following Brown's figure (1868); true size, no printing allowance

Also called: idler gear, wide face gear, module 1 30 teeth, rueda intermedia ancha, breites Zwischenrad

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

length
31.48 mm
width
31.41 mm
height
26.0 mm

Notes

  • Module 1, 20° involute, 30 teeth, pitch Ø30, 26 mm face: wide enough to mesh at once with three 8 mm gears stacked on one pin (Ferguson's paradox). Tips shortened to Ø31.5 (addendum 0.75 m) so they clear the base circle of the 21-tooth wheel with negative shift; Ø6 bore.
  • Xem Studio design following Brown's figure; true size, no printing allowance (apply your own to the mating features).

Spur gear, module 1, 30 T, 26 mm face (thick idler), Ø6 bore, tips… size chart

dimensionvalue
module1
teeth30
face26 mm
tip Ø31.5 mm
root Ø27.5 mm
boreØ6

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

spur-gear-m1-30t-w26-b6gear, z 0..26, a tooth centred on +XSTEP · 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=spur-gear-m1-30t-w26-b6

Spur gear, module 1, 30 T, 26 mm face (thick idler), Ø6 bore, tips at Ø31.5, isometric render of a generated part
Render of spur-gear-m1-30t-w26-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 a thick idler gear for?

Module 1, 20° involute, 30 teeth, pitch Ø30, 26 mm face: wide enough to mesh at once with three 8 mm gears stacked on one pin (Ferguson's paradox). Tips shortened to Ø31.5 (addendum 0.75 m) so they clear the base circle of the 21-tooth wheel with negative shift; Ø6 bore.