{
 "version": "2026-10-20",
 "license": "Dimension sheets are written by Xem Studio from the cited sources and are free to use (CC BY 4.0, attribute 'Xem Studio'). Linked files belong to their publishers under the license shown; Xem Studio does not host them. 'license_verified: false' means the license shown is from memory or the publisher's page as last read and should be confirmed at the link before commercial use.",
 "slug": "watt-linkage-coupler-30",
 "name": "Watt linkage coupler, 30 mm, centre tracer hole",
 "kind": "modern",
 "category": "Hardware",
 "group": "Mechanism parts",
 "year": null,
 "question": "What is the coupler in Watt's linkage?",
 "tags": [
  "mechanism part",
  "507 mechanical movements"
 ],
 "aliases": [
  "watt coupler",
  "watts linkage link",
  "acoplador de Watt",
  "Koppel des Wattschen Gestänges"
 ],
 "overall_mm": {
  "length": 40,
  "width": 10,
  "height": 5
 },
 "official_cad": false,
 "xem_status": "free-files",
 "les": false,
 "free_files": 1,
 "url": "https://xemstudio.com/objects/watt-linkage-coupler-30/",
 "sheet_txt": "https://xemstudio.com/objects/watt-linkage-coupler-30/sheet.txt",
 "sheet": {
  "basis": "Xem Studio design following Brown's figure (1868); true size, no printing allowance",
  "overall_mm": {
   "length": 40,
   "width": 10,
   "height": 5
  },
  "notes": [
   "10 × 5 mm link with Ø3 holes at −15, 0 and +15 mm: its ends pin to the two radius arms and its middle hole is the point that moves on a near-straight line.",
   "Xem Studio design following Brown's figure; true size, no printing allowance (apply your own to the mating features)."
  ],
  "table": {
   "columns": [
    "dimension",
    "value"
   ],
   "rows": [
    [
     "end centres",
     "30 mm"
    ],
    [
     "holes",
     "3 × Ø3"
    ]
   ]
  }
 },
 "sheet_text": "Watt linkage coupler, 30 mm, centre tracer hole — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/watt-linkage-coupler-30/  (CC BY 4.0)\nBasis: Xem Studio design following Brown's figure (1868); true size, no printing allowance\nCatalog version: 2026-10-20\n\nOverall (mm): length 40.0, width 10.0, height 5.0\n- 10 × 5 mm link with Ø3 holes at −15, 0 and +15 mm: its ends pin to the two radius arms and its middle hole is the point that moves on a near-straight line.\n- Xem Studio design following Brown's figure; true size, no printing allowance (apply your own to the mating features).\n\ndimension  value\nend centres  30 mm\nholes  3 × Ø3\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. 337: figure, his text and an animation — web — Publisher's page; dimensions are facts — https://507movements.com/mm_337.html\n- Xem Studio: drawing — web — Publisher's page; dimensions are facts — https://xemstudio.com/objects/watts-linkage-mechanism/\n\nFree files (CC BY 4.0, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/watt-linkage-coupler-30/index.json\nAPI: https://xemstudio.com/api/geometry?object=watt-linkage-coupler-30\n",
 "sources": [
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   "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. 337: figure, his text and an animation",
   "url": "https://507movements.com/mm_337.html",
   "formats": [
    "web"
   ],
   "license": "Publisher's page; dimensions are facts",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "Xem Studio",
   "title": "drawing",
   "url": "https://xemstudio.com/objects/watts-linkage-mechanism/",
   "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": [
  "watts-linkage-mechanism"
 ],
 "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": "What is the coupler in Watt's linkage?",
   "a": "10 × 5 mm link with Ø3 holes at −15, 0 and +15 mm: its ends pin to the two radius arms and its middle hole is the point that moves on a near-straight line."
  }
 ],
 "files_license": null,
 "offers": [
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   "file": "watt-linkage-coupler-30",
   "formats": [
    "step",
    "stl"
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   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/watt-linkage-coupler-30/watt-linkage-coupler-30.step",
   "stl": "https://xemstudio.com/files/hardware/watt-linkage-coupler-30/watt-linkage-coupler-30.stl",
   "note": "coupler, z 0..5"
  }
 ],
 "markdown": "https://xemstudio.com/objects/watt-linkage-coupler-30/index.md"
}