Gear cluster, module 1: 40 T / 20 T on one Ø14 hub, Ø8 bore — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/gear-cluster-m1-40-20-bore8/  (sheet CC BY 4.0; files Xem Studio Design License, https://xemstudio.com/license/)
Basis: Xem Studio design following Brown's figure (1868); true size, no printing allowance
Catalog version: 2026-10-20

Overall (mm): length 41.99, width 41.99, height 33.0
- Module 1 spur gears of 40, 20 teeth (8 mm faces at z = 16, 41) joined by a Ø14 hub into one part on a Ø8 shaft, a tooth of each on +X; each meshes at 30 mm centres with the pulley-and-gear unit of the complementary size (N₁ + N₂ = 60).
- Xem Studio design following Brown's figure; true size, no printing allowance (apply your own to the mating features).

dimension  value
gears  40 T / 20 T
module  1
hub  Ø14
bore  Ø8

Files elsewhere (not hosted by Xem Studio; license as stated by the publisher):
- Henry T. Brown (1868, public domain): Five Hundred and Seven Mechanical Movements — scan on archive.org — web — Publisher's page; dimensions are facts — https://archive.org/details/fivehundredseven00browiala
- 507movements.com: Brown's movement No. 58: figure, his text and an animation — web — Publisher's page; dimensions are facts — https://507movements.com/mm_058.html
- Xem Studio: drawing — web — Publisher's page; dimensions are facts — https://xemstudio.com/objects/belt-shifted-gears-two-speed-mechanism/

Free files (Xem Studio Design License, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/gear-cluster-m1-40-20-bore8/index.json
API: https://xemstudio.com/api/geometry?object=gear-cluster-m1-40-20-bore8