{
 "version": "2026-10-20",
 "license": "Dimension sheets: CC BY 4.0. Standard and published-size files: CC BY 4.0. Xem Studio's own designs (files_license = Xem Studio Design License): free to use and sell things from, not to redistribute as files — https://xemstudio.com/license/. Other publishers' files: their own license, linked beside them.",
 "slug": "tackle-rove-to-advantage-mechanism",
 "name": "Two single blocks rove to advantage (3 : 1)",
 "kind": "hardware",
 "category": "Mechanisms",
 "group": "Pulleys and tackle",
 "year": null,
 "question": "Why does it matter which block the hauling part leaves?",
 "tags": [
  "mechanism",
  "pulleys and tackle",
  "kinematics",
  "507 mechanical movements"
 ],
 "aliases": [
  "rove to advantage",
  "gun tackle",
  "luff tackle",
  "3 to 1 pulley",
  "aparejo a favor (3:1)",
  "Talje mit Vorteil geschoren (3:1)"
 ],
 "overall_mm": {
  "length": null,
  "width": null,
  "height": null
 },
 "official_cad": false,
 "xem_status": "free-files",
 "les": false,
 "free_files": 1,
 "url": "https://xemstudio.com/objects/tackle-rove-to-advantage-mechanism/",
 "sheet_txt": "https://xemstudio.com/objects/tackle-rove-to-advantage-mechanism/sheet.txt",
 "sheet": {
  "basis": "Xem Studio design following Brown No. 22 (1868)",
  "overall_mm": {
   "length": null,
   "width": null,
   "height": null
  },
  "notes": [
   "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."
  ],
  "table": {
   "columns": [
    "parameter",
    "value"
   ],
   "rows": [
    [
     "upper block",
     "pitch Ø40"
    ],
    [
     "lower block",
     "pitch Ø20 + arm"
    ],
    [
     "strands on the load",
     "3"
    ],
    [
     "mechanical advantage",
     "3 (2 if rove to disadvantage)"
    ]
   ]
  }
 },
 "sheet_text": "Two single blocks rove to advantage (3 : 1) — dimension sheet\nSource: 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/)\nBasis: Xem Studio design following Brown No. 22 (1868)\nCatalog version: 2026-10-20\n\nSizes: see table below\n- 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.\n- 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).\n- Brown's No. 22 (a pulley combination following the doubling rule).\n- 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.\n- Brown's movement No. 22 (1868) shows it; this model is a Xem Studio design following his figure, every part at true size.\n\nparameter  value\nupper block  pitch Ø40\nlower block  pitch Ø20 + arm\nstrands on the load  3\nmechanical advantage  3 (2 if rove to disadvantage)\n\nFiles elsewhere (not hosted by Xem Studio; license as stated by the publisher):\n- 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\n- 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\n\nFree files (Xem Studio Design License, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/tackle-rove-to-advantage-mechanism/index.json\nAPI: https://xemstudio.com/api/geometry?object=tackle-rove-to-advantage-mechanism\n",
 "sources": [
  {
   "publisher": "Henry T. Brown (1868, public domain)",
   "title": "Five Hundred and Seven Mechanical Movements — scan on archive.org",
   "url": "https://archive.org/details/fivehundredseven00browiala",
   "formats": [
    "web"
   ],
   "license": "Publisher's page; dimensions are facts",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "507movements.com",
   "title": "Brown's movement No. 22: figure, his text and an animation",
   "url": "https://507movements.com/mm_022.html",
   "formats": [
    "web"
   ],
   "license": "Publisher's page; dimensions are facts",
   "license_verified": true,
   "hosted": false
  }
 ],
 "xem": {
  "status": "free-files",
  "sheet_free": true,
  "mesh_price_usd": null,
  "step_price_usd": null,
  "tolerance_mm": null
 },
 "related": [
  "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"
 ],
 "fits": [],
 "dimensions": "exact (nominal, no printing tolerance)",
 "dimension_rule": "All geometry on Xem Studio is exact (nominal, true size) with no printing tolerance. Where a part meets another part, the object lists its mating features (feature, exact size, what it mates with, fit class: press, slide, run, socket, clamp or designed). Apply your process's allowance to those features only; 'designed' gaps are part of the design and stay as drawn.",
 "mating": [],
 "faq": [
  {
   "q": "Why does it matter which block the hauling part leaves?",
   "a": "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."
  }
 ],
 "files_license": {
  "name": "Xem Studio Design License",
  "holder": "Xem Studio",
  "url": "https://xemstudio.com/license/",
  "note": "Xem Studio's own design: free to use, print, modify and sell things made from it; not to be republished or redistributed as files."
 },
 "offers": [
  {
   "file": "tackle-rove-to-advantage-mechanism-assembly",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "Xem Studio Design License",
   "step": "https://xemstudio.com/files/hardware/tackle-rove-to-advantage-mechanism/tackle-rove-to-advantage-mechanism-assembly.step",
   "stl": "https://xemstudio.com/files/hardware/tackle-rove-to-advantage-mechanism/tackle-rove-to-advantage-mechanism-assembly.stl",
   "note": "Assembled mechanism, all parts placed at one pose (STEP keeps each part separate)"
  }
 ],
 "markdown": "https://xemstudio.com/objects/tackle-rove-to-advantage-mechanism/index.md"
}