{
 "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": "tri-clamp-spool-bored-honed",
 "name": "2 in × 3 in spool with the bore finished Ø48.00 (bored and honed power cylinder)",
 "kind": "hardware",
 "category": "Hardware",
 "group": "Stirling & thermoacoustic",
 "year": null,
 "question": "How do I turn a 2 in tri-clamp spool into a piston cylinder?",
 "tags": [
  "power cylinder",
  "bored spool",
  "honed",
  "piston",
  "custom spool",
  "tri-clamp",
  "stirling",
  "long earth society"
 ],
 "aliases": [
  "bored tri clamp spool",
  "tri clamp piston cylinder",
  "honed sanitary spool",
  "stirling power cylinder tri clamp"
 ],
 "overall_mm": {
  "length": null,
  "width": null,
  "height": null
 },
 "official_cad": false,
 "xem_status": "free-files",
 "les": true,
 "free_files": 1,
 "url": "https://xemstudio.com/objects/tri-clamp-spool-bored-honed/",
 "sheet_txt": "https://xemstudio.com/objects/tri-clamp-spool-bored-honed/sheet.txt",
 "sheet": {
  "basis": "Stock 2 in × 3 in spool (ISO 2852 faces, ASME BPE tube); the finished bore is a design value",
  "overall_mm": {
   "length": null,
   "width": null,
   "height": null
  },
  "notes": [
   "A standard 2 in × 3 in spool sent out to be bored and honed through to Ø48.00. Stock tube is made to its OD and wall, so its bore can be anywhere from about 46.8 to 48.0 mm and is not round to a sliding standard; Ø48.00 cleans up every tube in tolerance and leaves about 1.4 mm of wall.",
   "The bore is a running fit for the Ø48.00 × 34 clearance-seal piston (no rings): the honed bore and the piston's ground OD together are the seal. Both performance engines use it with a 36 mm stroke.",
   "Honed surface: the whole bore face to face. The faces stay as made."
  ],
  "table": {
   "columns": [
    "feature",
    "value"
   ],
   "rows": [
    [
     "faces",
     "ISO 2852 2 in, 76.2 face to face"
    ],
    [
     "finished bore",
     "Ø48.00 through, honed"
    ],
    [
     "piston",
     "Ø48.00 × 34"
    ],
    [
     "stroke",
     36
    ]
   ]
  }
 },
 "sheet_text": "2 in × 3 in spool with the bore finished Ø48.00 (bored and honed power cylinder) — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/tri-clamp-spool-bored-honed/  (CC BY 4.0)\nBasis: Stock 2 in × 3 in spool (ISO 2852 faces, ASME BPE tube); the finished bore is a design value\nCatalog version: 2026-10-20\n\nSizes: see table below\n- A standard 2 in × 3 in spool sent out to be bored and honed through to Ø48.00. Stock tube is made to its OD and wall, so its bore can be anywhere from about 46.8 to 48.0 mm and is not round to a sliding standard; Ø48.00 cleans up every tube in tolerance and leaves about 1.4 mm of wall.\n- The bore is a running fit for the Ø48.00 × 34 clearance-seal piston (no rings): the honed bore and the piston's ground OD together are the seal. Both performance engines use it with a 36 mm stroke.\n- Honed surface: the whole bore face to face. The faces stay as made.\n\nfeature  value\nfaces  ISO 2852 2 in, 76.2 face to face\nfinished bore  Ø48.00 through, honed\npiston  Ø48.00 × 34\nstroke  36.0\n\nFiles elsewhere (not hosted by Xem Studio; license as stated by the publisher):\n- ISO (via iTeh sample): ISO 2852 clamp liners: face profile and flange / groove diameters — PDF — standard excerpt; dimensions are facts — https://cdn.standards.iteh.ai/samples/7850/eb49c396488d408c8ced3e2961d76cf3/ISO-2852-1974.pdf\n- ASME: BPE Bioprocessing Equipment (clamp fitting dimensions, tube OD and wall) — standard — ASME; dimensions are facts [verify license at link] — https://www.asme.org/codes-standards/find-codes-standards/bpe-bioprocessing-equipment\n- Long Earth Society: Engine builds — web, video — LES site — https://longearthsociety.com/engineering/\n\nFree files (CC BY 4.0, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/tri-clamp-spool-bored-honed/index.json\nAPI: https://xemstudio.com/api/geometry?object=tri-clamp-spool-bored-honed\n",
 "sources": [
  {
   "publisher": "ISO (via iTeh sample)",
   "title": "ISO 2852 clamp liners: face profile and flange / groove diameters",
   "url": "https://cdn.standards.iteh.ai/samples/7850/eb49c396488d408c8ced3e2961d76cf3/ISO-2852-1974.pdf",
   "formats": [
    "PDF"
   ],
   "license": "standard excerpt; dimensions are facts",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "ASME",
   "title": "BPE Bioprocessing Equipment (clamp fitting dimensions, tube OD and wall)",
   "url": "https://www.asme.org/codes-standards/find-codes-standards/bpe-bioprocessing-equipment",
   "formats": [
    "standard"
   ],
   "license": "ASME; dimensions are facts",
   "license_verified": false,
   "hosted": false
  },
  {
   "publisher": "Long Earth Society",
   "title": "Engine builds",
   "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": [
  "stirling-clearance-seal-pistons",
  "tri-clamp-closed-hot-spool-bored",
  "list-tri-clamp-horizontal-gamma",
  "list-tri-clamp-charged-beta"
 ],
 "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": [
  {
   "feature": "faces",
   "exact": "ISO 2852 2 in, 76.2 face to face",
   "mates": "Type B gaskets, 2 in clamps",
   "fit": "clamp",
   "files": "all"
  },
  {
   "feature": "finished bore",
   "exact": "Ø48.00 through, honed",
   "mates": "Ø48.00 clearance-seal piston (no rings)",
   "fit": "run",
   "files": "all"
  }
 ],
 "fit_classes": {
  "press": "stays put: pin, tube, bearing or magnet held by interference. Typical FDM: hole +0.0 to +0.1 mm on diameter.",
  "slide": "assembles by hand and is held by a grub, pinch or clamp: shaft in a hub, rod in a socket, spigot in a bore. Typical FDM: +0.2 mm.",
  "run": "turns or slides in use: pin in a link, rod through a guide. Typical FDM: +0.3 mm.",
  "socket": "large sliding fit: syringe barrel, sleeve, bobbin in a bore. Typical FDM: +0.3 mm.",
  "clamp": "split part that closes on the mating part with screws: make it at size.",
  "designed": "a gap that is part of the design (piston fit option, displacer gap, air gap): do not change."
 },
 "faq": [
  {
   "q": "Does it need rings?",
   "a": "No: the piston is a clearance seal. Its leakage loss is in the engine's numbers for 10, 15 and 20 µm radial clearance."
  }
 ],
 "files_license": null,
 "offers": [
  {
   "file": "spool-2in-3in-bored-48.00",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/tri-clamp-spool-bored-honed/spool-2in-3in-bored-48.00.step",
   "stl": "https://xemstudio.com/files/hardware/tri-clamp-spool-bored-honed/spool-2in-3in-bored-48.00.stl",
   "note": "2 in × 3 in (76.2) spool, ISO 2852 faces, bore finished Ø48.00 through (honed: the piston's clearance seal)"
  }
 ],
 "markdown": "https://xemstudio.com/objects/tri-clamp-spool-bored-honed/index.md"
}