{
 "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": "internal-ring-gear-m1-60t",
 "name": "Internal (ring) gear, module 1, 60 teeth, Ø80",
 "kind": "modern",
 "category": "Hardware",
 "group": "Mechanism parts",
 "year": null,
 "question": "What size is a module 1, 60 tooth internal gear?",
 "tags": [
  "mechanism part",
  "507 mechanical movements"
 ],
 "aliases": [
  "internal gear",
  "ring gear",
  "annulus gear",
  "module 1 ring gear 60 teeth",
  "engranaje interior",
  "Hohlrad"
 ],
 "overall_mm": {
  "length": 80,
  "width": 80,
  "height": 8
 },
 "official_cad": false,
 "xem_status": "free-files",
 "les": false,
 "free_files": 1,
 "url": "https://xemstudio.com/objects/internal-ring-gear-m1-60t/",
 "sheet_txt": "https://xemstudio.com/objects/internal-ring-gear-m1-60t/sheet.txt",
 "sheet": {
  "basis": "Xem Studio design following Brown's figure (1868); true size, no printing allowance",
  "overall_mm": {
   "length": 80,
   "width": 80,
   "height": 8
  },
  "notes": [
   "Ring gear with 60 internal involute teeth, module 1, 20°: pitch Ø60, roots at Ø62.5 (rp + 1.25 m), tooth tips at Ø58.24 (addendum shortened to 0.88 m, the usual internal-gear correction that keeps the tips clear of the pinion's base-circle interference point); outside Ø80 × 8 with four Ø3.4 holes on a Ø71.25 circle.",
   "A pinion of N teeth meshes inside at centre distance m(60 − N)/2: 20 T at 20 mm, 30 T at 15 mm, 18 T planets around a 24 T sun at 21 mm.",
   "Xem Studio design following Brown's figure; true size, no printing allowance (apply your own to the mating features)."
  ],
  "table": {
   "columns": [
    "dimension",
    "value"
   ],
   "rows": [
    [
     "module",
     "1"
    ],
    [
     "teeth",
     "60 internal"
    ],
    [
     "pitch Ø",
     "60 mm"
    ],
    [
     "tip Ø (inside)",
     "58.24 mm"
    ],
    [
     "root Ø",
     "62.5 mm"
    ],
    [
     "outside",
     "Ø80 × 8 mm"
    ],
    [
     "holes",
     "4 × Ø3.4 on Ø71.25"
    ]
   ]
  }
 },
 "sheet_text": "Internal (ring) gear, module 1, 60 teeth, Ø80 — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/internal-ring-gear-m1-60t/  (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 80.0, width 80.0, height 8.0\n- Ring gear with 60 internal involute teeth, module 1, 20°: pitch Ø60, roots at Ø62.5 (rp + 1.25 m), tooth tips at Ø58.24 (addendum shortened to 0.88 m, the usual internal-gear correction that keeps the tips clear of the pinion's base-circle interference point); outside Ø80 × 8 with four Ø3.4 holes on a Ø71.25 circle.\n- A pinion of N teeth meshes inside at centre distance m(60 − N)/2: 20 T at 20 mm, 30 T at 15 mm, 18 T planets around a 24 T sun at 21 mm.\n- Xem Studio design following Brown's figure; true size, no printing allowance (apply your own to the mating features).\n\ndimension  value\nmodule  1\nteeth  60 internal\npitch Ø  60 mm\ntip Ø (inside)  58.24 mm\nroot Ø  62.5 mm\noutside  Ø80 × 8 mm\nholes  4 × Ø3.4 on Ø71.25\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. 34: figure, his text and an animation — web — Publisher's page; dimensions are facts — https://507movements.com/mm_034.html\n- Xem Studio: drawing — web — Publisher's page; dimensions are facts — https://xemstudio.com/objects/internal-gear-and-pinion-mechanism/\n\nFree files (CC BY 4.0, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/internal-ring-gear-m1-60t/index.json\nAPI: https://xemstudio.com/api/geometry?object=internal-ring-gear-m1-60t\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. 34: figure, his text and an animation",
   "url": "https://507movements.com/mm_034.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/internal-gear-and-pinion-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": [
  "internal-gear-and-pinion-mechanism",
  "epicyclic-gear-train-mechanism",
  "tusi-couple-straight-line-mechanism",
  "pinion-driving-internal-and-spur-gear-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 size is a module 1, 60 tooth internal gear?",
   "a": "Ring gear with 60 internal involute teeth, module 1, 20°: pitch Ø60, roots at Ø62.5 (rp + 1.25 m), tooth tips at Ø58.24 (addendum shortened to 0.88 m, the usual internal-gear correction that keeps the tips clear of the pinion's base-circle interference point); outside Ø80 × 8 with four Ø3.4 holes on a Ø71.25 circle."
  },
  {
   "q": "What is the centre distance of an internal gear and pinion?",
   "a": "m × (N_ring − N_pinion) / 2, e.g. 20 mm for 60 and 20 teeth at module 1."
  }
 ],
 "files_license": null,
 "offers": [
  {
   "file": "ring-gear-m1-60t",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/internal-ring-gear-m1-60t/ring-gear-m1-60t.step",
   "stl": "https://xemstudio.com/files/hardware/internal-ring-gear-m1-60t/ring-gear-m1-60t.stl",
   "note": "internal gear m1 60 T, Ø80 × 8, a space centred on +X"
  }
 ],
 "markdown": "https://xemstudio.com/objects/internal-ring-gear-m1-60t/index.md"
}