Xem Studiomeasured geometry

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Gear rack, module 1, 120 mm, full-depth 20° teeth

What are the tooth dimensions of a module 1 rack? · Modern device · basis: Xem Studio design following Brown's figure (1868); true size, no printing allowance

Also called: gear rack, module 1 rack, rack gear, linear gear, cremallera módulo 1, Zahnstange Modul 1

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

length
120.0 mm
width
11.0 mm
height
8.0 mm

Notes

  • Module 1 basic rack (ISO 53): straight 20° flanks, pitch π = 3.1416 mm, addendum 1 mm above the pitch line, dedendum 1.25 mm below it, tooth thickness π/2 on the pitch line; 120 × 8 mm, body to 10 mm below the pitch line, three Ø3.4 (M3 clearance) holes across it.
  • A module 1 pinion of N teeth sits with its axis N/2 mm above the pitch line and moves the rack πN mm per turn.
  • Xem Studio design following Brown's figure; true size, no printing allowance (apply your own to the mating features).

Gear rack, module 1, 120 mm, full-depth 20° teeth size chart

dimensionvalue
module1
pressure angle20°
pitch3.1416 mm
addendum / dedendum1 / 1.25 mm
length × width120 × 8 mm
pitch line to back10 mm
holes3 × Ø3.4 at x = −45, 0, 45

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. 113: 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

gear-rack-m1-120rack, pitch line y = 0, a tooth centred at x = 0, z 0..8STEP · STL
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Plain text: sheet.txt · JSON: /api/geometry?object=gear-rack-m1-120-full-depth

Gear rack, module 1, 120 mm, full-depth 20° teeth, isometric render of a generated part
Render of gear-rack-m1-120 from the free STEP; not to scale.

Fits with

Rack and pinion, module 1 (20 T pinion, 120 mm rack), isometric render of a generated part
Rack and pinion, module 1 (20 T pinion, 120 mm rack)5 sizes★ 1 file
Pinion between two racks (opposite motion, pump drive), isometric render of a generated part
Pinion between two racks (opposite motion, pump drive)4 sizes★ 1 file

Questions

What are the tooth dimensions of a module 1 rack?

Module 1 basic rack (ISO 53): straight 20° flanks, pitch π = 3.1416 mm, addendum 1 mm above the pitch line, dedendum 1.25 mm below it, tooth thickness π/2 on the pitch line; 120 × 8 mm, body to 10 mm below the pitch line, three Ø3.4 (M3 clearance) holes across it.