Two single blocks rove to advantage (3 : 1) — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/tackle-rove-to-advantage-mechanism/  (sheet CC BY 4.0; files Xem Studio Design License, https://xemstudio.com/license/)
Basis: Xem Studio design following Brown No. 22 (1868)
Catalog version: 2026-10-20

Sizes: see table below
- With one upper and one lower single block, the standing end can be made fast to the lower block and the hauling part led off it upward: then three strands act on the moving block and P = W/3. Rove the other way (hauling part off the fixed block) the same blocks give only 2 : 1.
- Pitch-Ø40 upper block, pitch-Ø20 lower block with an arm carrying the standing end 50 mm to the side; hauling part goes up at x = 40. The weight stem sits on the line of the three strands' resultant (x = 13.33).
- Brown's No. 22 (a pulley combination following the doubling rule).
- Parts (each has its own page): tackle-beam-240-sockets, tackle-block-20-top-stem, tackle-block-10-advantage, rope-sheave-3mm-pitch-40, rope-sheave-3mm-pitch-20, ropes-3mm-tackle-rove-to-advantage, tackle-weight-d40x40-socket, dowel-pins-metric.
- Brown's movement No. 22 (1868) shows it; this model is a Xem Studio design following his figure, every part at true size.

parameter  value
upper block  pitch Ø40
lower block  pitch Ø20 + arm
strands on the load  3
mechanical advantage  3 (2 if rove to disadvantage)

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. 22: figure, his text and an animation — web — Publisher's page; dimensions are facts — https://507movements.com/mm_022.html

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