Lifting tong arm 12 × 5: link hole 60 mm and foot 80 mm either side of the pivot — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/lifting-tong-arm-140-foot/  (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 153.81, width 19.33, height 5.0
- 12 × 5 flat arm with Ø3 holes for the link (60 mm from the pivot) and the crossing pivot, and at 80 mm beyond the pivot a 12 mm deep foot whose face is square to the load when the arms are crossed at ±22.02° on a 40 mm load. Two arms, one turned over, make the tongs.
- Xem Studio design following Brown's figure; true size, no printing allowance (apply your own to the mating features).

dimension  value
arm  140 mm between end holes, 12 × 5
holes  Ø3 at −60 and 0
foot  projects 10 mm, 12 deep
arm angle  ±22.02° on a 40 mm load

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. 494: figure, his text and an animation — web — Publisher's page; dimensions are facts — https://507movements.com/mm_494.html
- Xem Studio: drawing — web — Publisher's page; dimensions are facts — https://xemstudio.com/objects/lifting-tongs-mechanism/

Free files (Xem Studio Design License, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/lifting-tong-arm-140-foot/index.json
API: https://xemstudio.com/api/geometry?object=lifting-tong-arm-140-foot