Screw (fly) press: Tr16×4 screw in a C-frame nut — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/screw-press-mechanism/  (sheet CC BY 4.0; files Xem Studio Design License, https://xemstudio.com/license/)
Basis: Xem Studio design following Brown No. 105 (1868)
Catalog version: 2026-10-20

Sizes: see table below
- A coarse screw turns in a fixed nut at the top of a C-frame; its end comes down on the work. One turn = one lead (4 mm); the bar through the head gives the leverage: ideal force gain 2π × 40 / 4 ≈ 63, and in a fly press the weighted bar's momentum adds a blow.
- The catalog Tr16×4 jack screw is reused (basic ISO 2904 profile, drawn engaged in the frame's nut with no allowance); the frame is a Xem Studio design following Brown's figure. Drawn with the screw tip 10 mm above the foot.
- Brown's No. 105 (screw stamping press: rectilinear motion from circular).
- Parts (each has its own page): screw-jack-screw-tr16x4, screw-press-c-frame-tr16x4, tommy-bar-6x80.
- Brown's movement No. 105 (1868) shows it; this model is a Xem Studio design following his figure, every part at true size.

parameter  value
thread  Tr16×4
travel per turn  4 mm
lever  80 mm bar
ideal gain  ≈ 63

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. 105: figure, his text and an animation — web — Publisher's page; dimensions are facts — https://507movements.com/mm_105.html

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