Spur gears, module 1: 10 to 80 teeth (20° involute) — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/spur-gears-module-1/  (CC BY 4.0)
Basis: ISO 53 basic rack: 20° pressure angle, addendum m, dedendum 1.25 m; pitch Ø = m × teeth, tip Ø = m × (teeth + 2), root Ø = m × (teeth − 2.5)
Catalog version: 2026-10-20

Sizes: see table below
- Centre distance of two module 1 gears = m × (N1 + N2) / 2. Face width 8 mm, plain bore (add a hub, key or set screw to suit). Teeth below 17 are drawn without profile shift, so they undercut as real unshifted gears do.

teeth  pitch_dia_mm  tip_dia_mm  root_dia_mm  face_mm  bore_mm
10  10.0  12.0  7.5  8.0  3
12  12.0  14.0  9.5  8.0  3
14  14.0  16.0  11.5  8.0  4
15  15.0  17.0  12.5  8.0  4
16  16.0  18.0  13.5  8.0  5
18  18.0  20.0  15.5  8.0  5
20  20.0  22.0  17.5  8.0  6
22  22.0  24.0  19.5  8.0  7
24  24.0  26.0  21.5  8.0  8
25  25.0  27.0  22.5  8.0  8
28  28.0  30.0  25.5  8.0  9
30  30.0  32.0  27.5  8.0  10
32  32.0  34.0  29.5  8.0  10
35  35.0  37.0  32.5  8.0  11
36  36.0  38.0  33.5  8.0  12
40  40.0  42.0  37.5  8.0  13
42  42.0  44.0  39.5  8.0  14
45  45.0  47.0  42.5  8.0  15
48  48.0  50.0  45.5  8.0  16
50  50.0  52.0  47.5  8.0  17
56  56.0  58.0  53.5  8.0  19
60  60.0  62.0  57.5  8.0  20
64  64.0  66.0  61.5  8.0  22
70  70.0  72.0  67.5  8.0  24
72  72.0  74.0  69.5  8.0  24
80  80.0  82.0  77.5  8.0  25

Files elsewhere (not hosted by Xem Studio; license as stated by the publisher):
- ISO: ISO 53 standard basic rack (20° pressure angle, addendum 1 m, dedendum 1.25 m) and ISO 54 modules — standard — ISO; dimensions are facts [verify license at link] — https://www.iso.org/standard/5768.html

Free files (CC BY 4.0, Xem Studio; STEP + STL, 26 parts): https://xemstudio.com/files/hardware/spur-gears-module-1/index.json
API: https://xemstudio.com/api/geometry?object=spur-gears-module-1