Stone block 80 × 60 × 50 with a dovetail lewis hole 20 → 30 × 14, 30 deep — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/lewis-stone-block-80x60x50/  (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 80.0, width 60.0, height 50.0
- 80 × 60 × 50 block (the stone) with a dovetail hole in its top: 20 mm wide at the surface widening to 30 mm at 30 mm depth, 14 mm the other way — the undercut the lewis locks into.
- Xem Studio design following Brown's figure; true size, no printing allowance (apply your own to the mating features).

dimension  value
block  80 × 60 × 50 mm
hole at surface  20 × 14 mm
hole at bottom  30 × 14 mm
depth  30 mm

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. 493: figure, his text and an animation — web — Publisher's page; dimensions are facts — https://507movements.com/mm_493.html
- Xem Studio: drawing — web — Publisher's page; dimensions are facts — https://xemstudio.com/objects/lewis-stone-lifter-mechanism/

Free files (Xem Studio Design License, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/lewis-stone-block-80x60x50/index.json
API: https://xemstudio.com/api/geometry?object=lewis-stone-block-80x60x50