Spur gears, module 0.5: 10 to 80 teeth (20° involute) — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/spur-gears-module-0-5/  (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 0.5 gears = m × (N1 + N2) / 2. Face width 4 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  5.0  6.0  3.75  4.0  1.5
12  6.0  7.0  4.75  4.0  2.0
14  7.0  8.0  5.75  4.0  2.0
15  7.5  8.5  6.25  4.0  2.0
16  8.0  9.0  6.75  4.0  2.0
18  9.0  10.0  7.75  4.0  3
20  10.0  11.0  8.75  4.0  3
22  11.0  12.0  9.75  4.0  3
24  12.0  13.0  10.75  4.0  4
25  12.5  13.5  11.25  4.0  4
28  14.0  15.0  12.75  4.0  4
30  15.0  16.0  13.75  4.0  5
32  16.0  17.0  14.75  4.0  5
35  17.5  18.5  16.25  4.0  6
36  18.0  19.0  16.75  4.0  6
40  20.0  21.0  18.75  4.0  7
42  21.0  22.0  19.75  4.0  7
45  22.5  23.5  21.25  4.0  7
48  24.0  25.0  22.75  4.0  8
50  25.0  26.0  23.75  4.0  8
56  28.0  29.0  26.75  4.0  9
60  30.0  31.0  28.75  4.0  10
64  32.0  33.0  30.75  4.0  11
70  35.0  36.0  33.75  4.0  12
72  36.0  37.0  34.75  4.0  12
80  40.0  41.0  38.75  4.0  14

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-0-5/index.json
API: https://xemstudio.com/api/geometry?object=spur-gears-module-0-5