Pin (stud) clutch: studs on a sliding disc enter holes in a fixed disc — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/pin-clutch-mechanism/  (sheet CC BY 4.0; files Xem Studio Design License, https://xemstudio.com/license/)
Basis: Xem Studio design following Brown No. 52 (1868)
Catalog version: 2026-10-20

Sizes: see table below
- Two shafts end to end: one carries a disc with holes, the other a disc with studs that slides on a feather key. Pushed together, the studs enter the holes and the shafts turn as one; pulled back, they are free.
- Here Ø50 × 8 discs, four Ø6 studs on a 16 mm radius, Ø8 shafts with a 2 × 2 feather key; drawn engaged (studs fully home). Engage it only at rest or slow speed: it is a positive clutch, with no slip.
- Brown's No. 52.
- Parts (each has its own page): pin-clutch-disc-4-holes-50, pin-clutch-disc-4-studs-50-keyed, keyed-shaft-8x100-key2, feather-key-2x2x30, linear-shafts-h6.
- Brown's movement No. 52 (1868) shows it; this model is a Xem Studio design following his figure, every part at true size.

parameter  value
discs  2 × Ø50 × 8
studs  4 × Ø6 × 10 on R16
shafts  Ø8, key 2 × 2

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. 52: figure, his text and an animation — web — Publisher's page; dimensions are facts — https://507movements.com/mm_052.html

Free files (Xem Studio Design License, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/pin-clutch-mechanism/index.json
API: https://xemstudio.com/api/geometry?object=pin-clutch-mechanism