{
 "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": "glass-marbles",
 "name": "Glass marbles 1/2 in, 5/8 in and Ø16 mm",
 "kind": "standard",
 "category": "Hardware",
 "group": "Found & household materials",
 "year": null,
 "question": "What is the diameter of a standard marble?",
 "tags": [
  "marble",
  "glass",
  "ball",
  "sphere",
  "found materials",
  "stirling",
  "long earth society"
 ],
 "aliases": [
  "marble diameter",
  "marble size mm",
  "shooter marble size",
  "16mm marble",
  "marble stl",
  "5/8 inch marble mm",
  "1/2 inch marble",
  "marble stirling engine"
 ],
 "overall_mm": {
  "length": null,
  "width": null,
  "height": null
 },
 "official_cad": false,
 "xem_status": "free-files",
 "les": true,
 "free_files": 3,
 "url": "https://xemstudio.com/objects/glass-marbles/",
 "sheet_txt": "https://xemstudio.com/objects/glass-marbles/sheet.txt",
 "sheet": {
  "basis": "Marbles are sized by diameter in 1/16 in steps, usually 1/2 to 3/4 in (marblecollecting.com); files are spheres at 1/2 in (Ø12.70), 5/8 in (Ø15.875) and Ø16.0",
  "overall_mm": {
   "length": null,
   "width": null,
   "height": null
  },
  "notes": [
   "Glass marbles are sized by diameter in 1/16 in steps and are usually 1/2 to 3/4 in. The files are spheres at 1/2 in (Ø12.70), 5/8 in (Ø15.875) and the metric Ø16.0.",
   "Tournament rules put shooters between 5/8 and 3/4 in.",
   "In the test-tube marble engine, four 5/8 in marbles roll inside a 25 × 150 tube (Ø22.6 bore) as the displacer; one marble fits across the bore, so they roll in single file.",
   "Marbles vary from piece to piece by a few tenths of a millimetre; measure the one you have before you draw anything around it."
  ],
  "table": {
   "columns": [
    "marble",
    "dia_in",
    "dia_mm"
   ],
   "rows": [
    [
     "1/2 in",
     "1/2",
     12.7
    ],
    [
     "5/8 in",
     "5/8",
     15.875
    ],
    [
     "16 mm",
     null,
     16
    ]
   ]
  }
 },
 "sheet_text": "Glass marbles 1/2 in, 5/8 in and Ø16 mm — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/glass-marbles/  (CC BY 4.0)\nBasis: Marbles are sized by diameter in 1/16 in steps, usually 1/2 to 3/4 in (marblecollecting.com); files are spheres at 1/2 in (Ø12.70), 5/8 in (Ø15.875) and Ø16.0\nCatalog version: 2026-10-20\n\nSizes: see table below\n- Glass marbles are sized by diameter in 1/16 in steps and are usually 1/2 to 3/4 in. The files are spheres at 1/2 in (Ø12.70), 5/8 in (Ø15.875) and the metric Ø16.0.\n- Tournament rules put shooters between 5/8 and 3/4 in.\n- In the test-tube marble engine, four 5/8 in marbles roll inside a 25 × 150 tube (Ø22.6 bore) as the displacer; one marble fits across the bore, so they roll in single file.\n- Marbles vary from piece to piece by a few tenths of a millimetre; measure the one you have before you draw anything around it.\n\nmarble  dia_in  dia_mm\n1/2 in  1/2  12.7\n5/8 in  5/8  15.875\n16 mm  None  16.0\n\nFiles elsewhere (not hosted by Xem Studio; license as stated by the publisher):\n- Wikipedia: Craft stick — web — CC BY-SA 4.0 (text) — https://en.wikipedia.org/wiki/Craft_stick\n- Wikipedia: BB gun — web — CC BY-SA 4.0 (text) — https://en.wikipedia.org/wiki/BB_gun\n- Wikipedia: Table tennis — web — CC BY-SA 4.0 (text) — https://en.wikipedia.org/wiki/Table_tennis\n- Long Earth Society: Engine builds (videos and write-ups) — web, video — LES site — https://longearthsociety.com/engineering/\n\nFree files (CC BY 4.0, Xem Studio; STEP + STL, 3 parts): https://xemstudio.com/files/hardware/glass-marbles/index.json\nAPI: https://xemstudio.com/api/geometry?object=glass-marbles\n",
 "sources": [
  {
   "publisher": "Wikipedia",
   "title": "Craft stick",
   "url": "https://en.wikipedia.org/wiki/Craft_stick",
   "formats": [
    "web"
   ],
   "license": "CC BY-SA 4.0 (text)",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "Wikipedia",
   "title": "BB gun",
   "url": "https://en.wikipedia.org/wiki/BB_gun",
   "formats": [
    "web"
   ],
   "license": "CC BY-SA 4.0 (text)",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "Wikipedia",
   "title": "Table tennis",
   "url": "https://en.wikipedia.org/wiki/Table_tennis",
   "formats": [
    "web"
   ],
   "license": "CC BY-SA 4.0 (text)",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "Long Earth Society",
   "title": "Engine builds (videos and write-ups)",
   "url": "https://longearthsociety.com/engineering/",
   "formats": [
    "web",
    "video"
   ],
   "license": "LES site",
   "license_verified": true,
   "hosted": false
  }
 ],
 "xem": {
  "status": "free-files",
  "sheet_free": true,
  "mesh_price_usd": null,
  "step_price_usd": null,
  "tolerance_mm": null
 },
 "related": [
  "steel-and-airsoft-bbs",
  "ping-pong-ball",
  "ball-bearings-metric",
  "list-test-tube-marble-engine",
  "borosilicate-test-tubes"
 ],
 "fits": [
  {
   "role": "Goes in or on",
   "items": [
    {
     "slug": "borosilicate-test-tubes",
     "why": "the marble displacer of the test-tube engine"
    }
   ]
  },
  {
   "role": "Alternatives",
   "items": [
    {
     "slug": "steel-and-airsoft-bbs",
     "why": "smaller balls, Ø4.5 and Ø6"
    },
    {
     "slug": "ping-pong-ball",
     "why": "a larger, hollow, much lighter ball (Ø40)"
    }
   ]
  }
 ],
 "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 diameter of a marble?",
   "a": "Marbles come in 1/16 in steps, usually 1/2 to 3/4 in; the common size is 5/8 in (15.875 mm, often sold as 16 mm)."
  },
  {
   "q": "Are marbles all the same size?",
   "a": "No; they are sized by the smallest sieve opening they pass, and individual marbles vary by a few tenths of a millimetre."
  },
  {
   "q": "What marbles go in a test-tube marble engine?",
   "a": "5/8 in (Ø15.875) in a 25 × 150 tube (Ø22.6 bore): they roll in single file from end to end as the tube rocks."
  }
 ],
 "files_license": null,
 "offers": [
  {
   "file": "marble-16mm",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/sticks-skewers-wire-bbs/marble-16mm.step",
   "stl": "https://xemstudio.com/files/hardware/sticks-skewers-wire-bbs/marble-16mm.stl",
   "note": "glass marble Ø16 (15.9); shooter Ø25"
  },
  {
   "file": "marble-5-8in",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/sticks-skewers-wire-bbs/marble-5-8in.step",
   "stl": "https://xemstudio.com/files/hardware/sticks-skewers-wire-bbs/marble-5-8in.stl",
   "note": "glass marble 5/8 in (Ø15.875), the common size"
  },
  {
   "file": "marble-1-2in",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/sticks-skewers-wire-bbs/marble-1-2in.step",
   "stl": "https://xemstudio.com/files/hardware/sticks-skewers-wire-bbs/marble-1-2in.stl",
   "note": "glass marble 1/2 in (Ø12.70)"
  }
 ],
 "markdown": "https://xemstudio.com/objects/glass-marbles/index.md"
}