{
 "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": "geneva-stop-finger-wheel-r23-5-pin4",
 "name": "Geneva stop finger wheel: Ø4 pin at r 23.51, Ø41.02 locking disc, Ø6 bore",
 "kind": "modern",
 "category": "Mechanisms",
 "group": "Intermittent motion",
 "year": null,
 "question": "What is the finger wheel of a Geneva stop?",
 "tags": [
  "mechanism part",
  "507 mechanical movements"
 ],
 "aliases": [
  "geneva driver",
  "finger wheel",
  "maltese cross driver",
  "stop work finger",
  "rueda de dedo de cruz de Malta",
  "Fingerrad des Malteserkreuz-Gesperrs"
 ],
 "overall_mm": {
  "length": 53.02,
  "width": 53.02,
  "height": 10
 },
 "official_cad": false,
 "xem_status": "free-files",
 "les": false,
 "free_files": 1,
 "url": "https://xemstudio.com/objects/geneva-stop-finger-wheel-r23-5-pin4/",
 "sheet_txt": "https://xemstudio.com/objects/geneva-stop-finger-wheel-r23-5-pin4/sheet.txt",
 "sheet": {
  "basis": "Xem Studio design following Brown's figure (1868); true size, no printing allowance",
  "overall_mm": {
   "length": 53.02,
   "width": 53.02,
   "height": 10
  },
  "notes": [
   "Driver of a Geneva (Maltese cross) stop for a star on 40 mm centres: one Ø4 × 6 pin at radius 23.51 (= a·sin(π/5), so it enters and leaves the star's slots radially), a Ø41.02 × 6 locking disc that holds the star still between indexings, and a Ø53.02 × 4 carrier plate under both; Ø6 bore.",
   "The locking disc is cut back by the exact sweep of the star through one indexing (the star's outline in the wheel's frame at every 0.1° of the 108° engagement, a clearance surface kept as 0 mm facets), so disc and star only ever touch: on the disc's rim while locked, on the pin while indexing.",
   "Xem Studio design following Brown's figure; true size, no printing allowance (apply your own to the mating features)."
  ],
  "table": {
   "columns": [
    "dimension",
    "value"
   ],
   "rows": [
    [
     "pin",
     "Ø4 at r 23.51"
    ],
    [
     "locking disc",
     "Ø41.02 × 6"
    ],
    [
     "carrier",
     "Ø53.02 × 4"
    ],
    [
     "centres with the star",
     "40 mm"
    ],
    [
     "engagement",
     "±54° of the wheel's turn"
    ],
    [
     "bore",
     "Ø6"
    ]
   ]
  }
 },
 "sheet_text": "Geneva stop finger wheel: Ø4 pin at r 23.51, Ø41.02 locking disc, Ø6 bore — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/geneva-stop-finger-wheel-r23-5-pin4/  (sheet CC BY 4.0; files Xem Studio Design License, https://xemstudio.com/license/)\nBasis: Xem Studio design following Brown's figure (1868); true size, no printing allowance\nCatalog version: 2026-10-20\n\nOverall (mm): length 53.02, width 53.02, height 10.0\n- Driver of a Geneva (Maltese cross) stop for a star on 40 mm centres: one Ø4 × 6 pin at radius 23.51 (= a·sin(π/5), so it enters and leaves the star's slots radially), a Ø41.02 × 6 locking disc that holds the star still between indexings, and a Ø53.02 × 4 carrier plate under both; Ø6 bore.\n- The locking disc is cut back by the exact sweep of the star through one indexing (the star's outline in the wheel's frame at every 0.1° of the 108° engagement, a clearance surface kept as 0 mm facets), so disc and star only ever touch: on the disc's rim while locked, on the pin while indexing.\n- Xem Studio design following Brown's figure; true size, no printing allowance (apply your own to the mating features).\n\ndimension  value\npin  Ø4 at r 23.51\nlocking disc  Ø41.02 × 6\ncarrier  Ø53.02 × 4\ncentres with the star  40 mm\nengagement  ±54° of the wheel's turn\nbore  Ø6\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. 212: figure, his text and an animation — web — Publisher's page; dimensions are facts — https://507movements.com/mm_212.html\n- Xem Studio: drawing — web — Publisher's page; dimensions are facts — https://xemstudio.com/objects/geneva-stop-winding-stop-mechanism/\n\nFree files (Xem Studio Design License, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/geneva-stop-finger-wheel-r23-5-pin4/index.json\nAPI: https://xemstudio.com/api/geometry?object=geneva-stop-finger-wheel-r23-5-pin4\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. 212: figure, his text and an animation",
   "url": "https://507movements.com/mm_212.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/geneva-stop-winding-stop-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": [
  "geneva-stop-winding-stop-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 finger wheel of a Geneva stop?",
   "a": "Driver of a Geneva (Maltese cross) stop for a star on 40 mm centres: one Ø4 × 6 pin at radius 23.51 (= a·sin(π/5), so it enters and leaves the star's slots radially), a Ø41.02 × 6 locking disc that holds the star still between indexings, and a Ø53.02 × 4 carrier plate under both; Ø6 bore."
  }
 ],
 "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": "geneva-stop-finger-wheel-r23-5-pin4",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "Xem Studio Design License",
   "step": "https://xemstudio.com/files/hardware/geneva-stop-finger-wheel-r23-5-pin4/geneva-stop-finger-wheel-r23-5-pin4.step",
   "stl": "https://xemstudio.com/files/hardware/geneva-stop-finger-wheel-r23-5-pin4/geneva-stop-finger-wheel-r23-5-pin4.stl",
   "note": "finger wheel, axis Z, disc z 0..6, carrier z -4..0, pin on +X"
  }
 ],
 "markdown": "https://xemstudio.com/objects/geneva-stop-finger-wheel-r23-5-pin4/index.md"
}