Double rack frame, module 1, racks 20 mm apart (120 × 44) — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/double-rack-frame-120/  (CC BY 4.0)
Basis: Xem Studio design following Brown's figure (1868); true size, no printing allowance
Catalog version: 2026-10-20

Overall (mm): length 120.0, width 44.0, height 8.0
- 120 × 44 × 8 frame with two facing module 1 racks whose pitch lines are 20 mm apart (one pitch diameter of a 20-tooth pinion), teeth in phase; a half-toothed pinion between them drives the frame one way on the upper rack and back on the lower.
- Xem Studio design following Brown's figure; true size, no printing allowance (apply your own to the mating features).

dimension  value
frame  120 × 44 × 8 mm
racks  module 1, 96 mm, pitch lines 20 mm apart
end holes  2 × Ø3 for guide rods/pins

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. 114: figure, his text and an animation — web — Publisher's page; dimensions are facts — https://507movements.com/mm_114.html
- Xem Studio: drawing — web — Publisher's page; dimensions are facts — https://xemstudio.com/objects/mutilated-gear-double-rack-mechanism/

Free files (CC BY 4.0, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/double-rack-frame-120/index.json
API: https://xemstudio.com/api/geometry?object=double-rack-frame-120