{
 "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": "recoil-anchor-for-30t-d50",
 "name": "Recoil anchor for the 30-tooth Ø50 escape wheel",
 "kind": "modern",
 "category": "Hardware",
 "group": "Mechanism parts",
 "year": null,
 "question": "What is a recoil anchor?",
 "tags": [
  "mechanism part",
  "507 mechanical movements"
 ],
 "aliases": [
  "recoil anchor",
  "clock anchor",
  "escapement pallets",
  "áncora de escape de retroceso",
  "Anker (rückfallend)"
 ],
 "overall_mm": {
  "length": 44.96,
  "width": 25.47,
  "height": 3
 },
 "official_cad": false,
 "xem_status": "free-files",
 "les": false,
 "free_files": 1,
 "url": "https://xemstudio.com/objects/recoil-anchor-for-30t-d50/",
 "sheet_txt": "https://xemstudio.com/objects/recoil-anchor-for-30t-d50/sheet.txt",
 "sheet": {
  "basis": "Xem Studio design following Brown's figure (1868); true size, no printing allowance",
  "overall_mm": {
   "length": 44.96,
   "width": 25.47,
   "height": 3
  },
  "notes": [
   "3 mm anchor pivoting on a Ø3 pin 35.36 mm above the escape wheel's centre, its two pallets spanning 7½ teeth (90°), each pallet 1.6 mm thick with its impulse face at the deep end. The locking faces are straight, their deep ends 0.3 mm off the pivot circle, so the swinging anchor pushes the wheel back a little after locking: the recoil.",
   "Xem Studio design following Brown's figure; true size, no printing allowance (apply your own to the mating features)."
  ],
  "table": {
   "columns": [
    "dimension",
    "value"
   ],
   "rows": [
    [
     "pivot above wheel centre",
     "35.36 mm"
    ],
    [
     "span",
     "7½ teeth (90°)"
    ],
    [
     "pallet thickness",
     "1.6 mm"
    ],
    [
     "pivot hole",
     "Ø3"
    ],
    [
     "thickness",
     "3 mm"
    ]
   ]
  }
 },
 "sheet_text": "Recoil anchor for the 30-tooth Ø50 escape wheel — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/recoil-anchor-for-30t-d50/  (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 44.96, width 25.47, height 3.0\n- 3 mm anchor pivoting on a Ø3 pin 35.36 mm above the escape wheel's centre, its two pallets spanning 7½ teeth (90°), each pallet 1.6 mm thick with its impulse face at the deep end. The locking faces are straight, their deep ends 0.3 mm off the pivot circle, so the swinging anchor pushes the wheel back a little after locking: the recoil.\n- Xem Studio design following Brown's figure; true size, no printing allowance (apply your own to the mating features).\n\ndimension  value\npivot above wheel centre  35.36 mm\nspan  7½ teeth (90°)\npallet thickness  1.6 mm\npivot hole  Ø3\nthickness  3 mm\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. 288: figure, his text and an animation — web — Publisher's page; dimensions are facts — https://507movements.com/mm_288.html\n- Xem Studio: drawing — web — Publisher's page; dimensions are facts — https://xemstudio.com/objects/recoil-anchor-escapement-mechanism/\n\nFree files (CC BY 4.0, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/recoil-anchor-for-30t-d50/index.json\nAPI: https://xemstudio.com/api/geometry?object=recoil-anchor-for-30t-d50\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. 288: figure, his text and an animation",
   "url": "https://507movements.com/mm_288.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/recoil-anchor-escapement-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": [
  "recoil-anchor-escapement-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 a recoil anchor?",
   "a": "3 mm anchor pivoting on a Ø3 pin 35.36 mm above the escape wheel's centre, its two pallets spanning 7½ teeth (90°), each pallet 1.6 mm thick with its impulse face at the deep end. The locking faces are straight, their deep ends 0.3 mm off the pivot circle, so the swinging anchor pushes the wheel back a little after locking: the recoil."
  }
 ],
 "files_license": null,
 "offers": [
  {
   "file": "recoil-anchor-for-30t-d50",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/recoil-anchor-for-30t-d50/recoil-anchor-for-30t-d50.step",
   "stl": "https://xemstudio.com/files/hardware/recoil-anchor-for-30t-d50/recoil-anchor-for-30t-d50.stl",
   "note": "anchor, z 0..3, pivot at (0, 35.36)"
  }
 ],
 "markdown": "https://xemstudio.com/objects/recoil-anchor-for-30t-d50/index.md"
}