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Single Spanish burton (3 : 1)

How does a Spanish burton get 3 : 1 from two single blocks? · Hardware · basis: Xem Studio design following Brown No. 16 (1868)

Also called: spanish burton, spanish barton, runner tackle, 3 to 1 pulley, aparejo español (burton), Spanische Talje

Exact dimensions. True size, with no printing tolerance added.

sizes
4 in table

Notes

  • Rope 1 runs from the load over a fixed block and down to a runner block; rope 2 runs from the load over the runner and down to the hand. The runner is pulled down by both legs of rope 2 (2P) and held by rope 1, so rope 1 carries 2P; the load gets 2P + P: P = W/3.
  • Here a pitch-Ø40 fixed block and a pitch-Ø20 runner; the two rope ends sit 30 mm apart on a load bar whose weight stem is on the line of the resultant (x = −10).
  • Brown's No. 16 (Spanish barton). It is the 'third system' of pulleys with two sheaves: every rope ends on the load.
  • Parts (each has its own page): tackle-beam-240-sockets, tackle-block-20-top-stem, tackle-block-10-top-socket, rope-sheave-3mm-pitch-40, rope-sheave-3mm-pitch-20, ropes-3mm-spanish-burton-single, tackle-weight-d40x40-socket, load-bar-40-sockets-m20-p10, dowel-pins-metric.
  • Brown's movement No. 16 (1868) shows it; this model is a Xem Studio design following his figure, every part at true size.

Single Spanish burton size chart

parametervalue
fixed blockpitch Ø40
runnerpitch Ø20
rope tensionsrope 1: 2P, rope 2: P
mechanical advantage3

Where the files are

Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.

Henry T. Brown (1868, public domain)Five Hundred and Seven Mechanical Movements — scan on archive.orgwebPublisher's page; dimensions are facts
507movements.comBrown's movement No. 16: figure, his text and an animationwebPublisher's page; dimensions are facts

Free files

★ Free files 1 parts. Xem Studio design: free to use, print and sell things from; not to be republished as files. Xem Studio Design License. index.json

spanish-burton-single-mechanism-assemblyAssembled mechanism, all parts placed at one pose (STEP keeps each part separate)STEP · STL
Let your AI pull this. Add https://xemstudio.com/mcp to Claude, ChatGPT, Cursor or any MCP client (free, no account, one minute) and it can look up exact sizes, mating fits and free STEP/STL from every chat.
Set it up →

Plain text: sheet.txt · JSON: /api/geometry?object=spanish-burton-single-mechanism

Single Spanish burton (3 : 1), isometric render of a generated part
Render of spanish-burton-single-mechanism-assembly from the free STEP; not to scale.

Fits with

Tackle beam 240 × 20 × 12 with Ø3 sockets every 5 mm, isometric render of a generated part
Tackle beam 240 × 20 × 12 with Ø3 sockets every 5 mm240.0×20.0×12.0 mm★ 1 file
Single block for a pitch-Ø40 sheave, stem up (fixed block), isometric render of a generated part
Single block for a pitch-Ø40 sheave, stem up (fixed block)50.4×13.0×68.2 mm★ 1 file
Single runner block for a pitch-Ø20 sheave, rope socket on top, isometric render of a generated part
Single runner block for a pitch-Ø20 sheave, rope socket on top30.4×13.0×35.2 mm★ 1 file
Rope sheave for Ø3 rope, pitch Ø40 (rope centre), Ø44.4 rim, Ø4 bore, isometric render of a generated part
Rope sheave for Ø3 rope, pitch Ø40 (rope centre), Ø44.4 rim, Ø4 bore44.4×8.0×44.4 mm★ 1 file
Rope sheave for Ø3 rope, pitch Ø20 (rope centre), Ø24.4 rim, Ø4 bore, isometric render of a generated part
Rope sheave for Ø3 rope, pitch Ø20 (rope centre), Ø24.4 rim, Ø4 bore24.4×8.0×24.4 mm★ 1 file
Ø3 ropes for the single spanish burton (drawn in place), isometric render of a generated part
Ø3 ropes for the single spanish burton (drawn in place)43.0×3.0×181.5 mm★ 2 files
Weight Ø40 × 40 with a Ø3 top socket (394.58 g in steel), isometric render of a generated part
Weight Ø40 × 40 with a Ø3 top socket (394.58 g in steel)40.0×40.0×40.0 mm★ 1 file
Load bar 40 × 10 × 8 with 2 rope sockets and a weight stem, isometric render of a generated part
Load bar 40 × 10 × 8 with 2 rope sockets and a weight stem40.0×10.0×16.0 mm★ 1 file
Dowel pins, 2–6 mm (ISO 2338 / DIN 6325), isometric render of a generated part
Dowel pins, 2–6 mm (ISO 2338 / DIN 6325)5 sizes★ 23 files

Questions

How does a Spanish burton get 3 : 1 from two single blocks?

Rope 1 runs from the load over a fixed block and down to a runner block; rope 2 runs from the load over the runner and down to the hand. The runner is pulled down by both legs of rope 2 (2P) and held by rope 1, so rope 1 carries 2P; the load gets 2P + P: P = W/3.