{
 "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": "crosshead-guide-8mm",
 "name": "Crosshead guide, Ø8 bore × 30",
 "kind": "hardware",
 "category": "Stirling engines",
 "group": "Drives & mechanisms",
 "year": null,
 "question": "What guide does an 8 mm crosshead run in?",
 "tags": [
  "crosshead",
  "guide",
  "gamma",
  "stirling",
  "long earth society"
 ],
 "aliases": [
  "crosshead guide",
  "8mm slider guide",
  "crosshead bushing"
 ],
 "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/crosshead-guide-8mm/",
 "sheet_txt": "https://xemstudio.com/objects/crosshead-guide-8mm/sheet.txt",
 "sheet": {
  "basis": "Bore at the Ø8 crosshead (fit: run); M3 clearance Ø3.4 (ISO 273)",
  "overall_mm": {
   "length": null,
   "width": null,
   "height": null
  },
  "notes": [
   "A tube Ø16 outside with a Ø8 bore, 30 long, that the Ø8 crosshead runs in (fit: run).",
   "A 32 × 10 × 4 flange at its base has 2 × Ø3.4 holes 22 mm apart for M3 screws."
  ],
  "table": {
   "columns": [
    "parameter",
    "value"
   ],
   "rows": [
    [
     "bore",
     8
    ],
    [
     "outside",
     16
    ],
    [
     "length",
     30
    ],
    [
     "flange",
     "32 × 10 × 4"
    ],
    [
     "holes",
     "2 × Ø3.4 at 22"
    ]
   ]
  }
 },
 "sheet_text": "Crosshead guide, Ø8 bore × 30 — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/crosshead-guide-8mm/  (CC BY 4.0)\nBasis: Bore at the Ø8 crosshead (fit: run); M3 clearance Ø3.4 (ISO 273)\nCatalog version: 2026-10-20\n\nSizes: see table below\n- A tube Ø16 outside with a Ø8 bore, 30 long, that the Ø8 crosshead runs in (fit: run).\n- A 32 × 10 × 4 flange at its base has 2 × Ø3.4 holes 22 mm apart for M3 screws.\n\nparameter  value\nbore  8\noutside  16\nlength  30\nflange  32 × 10 × 4\nholes  2 × Ø3.4 at 22\n\nFiles elsewhere (not hosted by Xem Studio; license as stated by the publisher):\n- Wikipedia: Crosshead — web — CC BY-SA 4.0 (text) — https://en.wikipedia.org/wiki/Crosshead\n- Wikipedia: Piston — web — CC BY-SA 4.0 (text) — https://en.wikipedia.org/wiki/Piston\n- James R. Senft: Miniature Stirling engine piston fits (LTD book) — book — reference [verify license at link] — https://www.stirlingengine.com/\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/crosshead-guide-8mm/index.json\nAPI: https://xemstudio.com/api/geometry?object=crosshead-guide-8mm\n",
 "sources": [
  {
   "publisher": "Wikipedia",
   "title": "Crosshead",
   "url": "https://en.wikipedia.org/wiki/Crosshead",
   "formats": [
    "web"
   ],
   "license": "CC BY-SA 4.0 (text)",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "Wikipedia",
   "title": "Piston",
   "url": "https://en.wikipedia.org/wiki/Piston",
   "formats": [
    "web"
   ],
   "license": "CC BY-SA 4.0 (text)",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "James R. Senft",
   "title": "Miniature Stirling engine piston fits (LTD book)",
   "url": "https://www.stirlingengine.com/",
   "formats": [
    "book"
   ],
   "license": "reference",
   "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": [
  "crosshead-8mm",
  "power-cylinder-liner",
  "power-piston"
 ],
 "fits": [
  {
   "role": "Goes in or on",
   "items": [
    {
     "slug": "tri-clamp-engine-base-plate",
     "why": "flanged to the frame in line with the liner"
    }
   ]
  },
  {
   "role": "Connects to",
   "items": [
    {
     "slug": "crosshead-8mm",
     "why": "crosshead runs in the bore"
    }
   ]
  },
  {
   "role": "Also needed",
   "items": [
    {
     "slug": "socket-head-cap-screws-metric",
     "why": "2 × M3"
    }
   ]
  }
 ],
 "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": "guide bore",
   "exact": "Ø8",
   "mates": "crosshead OD",
   "fit": "run",
   "files": "crosshead-guide-"
  },
  {
   "feature": "guide flange holes",
   "exact": "Ø3.4",
   "mates": "M3 screw clearance",
   "fit": "designed",
   "files": "crosshead-guide-"
  }
 ],
 "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": "What bore is the crosshead guide?",
   "a": "Ø8, the crosshead's outside diameter; fit: run."
  },
  {
   "q": "How is the crosshead guide mounted?",
   "a": "Two M3 screws through the flange, 22 mm apart."
  }
 ],
 "files_license": null,
 "offers": [
  {
   "file": "crosshead-guide-8mm",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/power-cylinder-piston-crosshead/crosshead-guide-8mm.step",
   "stl": "https://xemstudio.com/files/hardware/power-cylinder-piston-crosshead/crosshead-guide-8mm.stl",
   "note": "crosshead guide: Ø8 bore (the crosshead OD, exact) × 30, flange with 2 × M3 clearance (Ø3.4)"
  }
 ],
 "markdown": "https://xemstudio.com/objects/crosshead-guide-8mm/index.md"
}