{
 "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": "mgn-rails",
 "name": "MGN9, MGN12 and MGN15 rails, 150 to 400 mm",
 "kind": "hardware",
 "category": "Hardware",
 "group": "Motion",
 "year": null,
 "question": "What are the MGN12 rail dimensions and hole spacing?",
 "tags": [
  "linear rail",
  "mgn",
  "rail",
  "linear guide"
 ],
 "aliases": [
  "mgn12 rail dimensions",
  "mgn9 rail hole spacing",
  "mgn15 rail",
  "linear rail step file",
  "mgn rail counterbore"
 ],
 "overall_mm": {
  "length": null,
  "width": null,
  "height": null
 },
 "official_cad": false,
 "xem_status": "free-files",
 "les": false,
 "free_files": 12,
 "url": "https://xemstudio.com/objects/mgn-rails/",
 "sheet_txt": "https://xemstudio.com/objects/mgn-rails/sheet.txt",
 "sheet": {
  "basis": "HIWIN MGN catalogue rail section, hole pitch and counterbore (other brands match)",
  "overall_mm": {
   "length": null,
   "width": null,
   "height": null
  },
  "notes": [
   "Rail section W × H: MGN9 9 × 6.5; MGN12 12 × 8; MGN15 15 × 10. Lengths 150, 200, 300, 400.",
   "Holes Ø3.5 through with a Ø6 counterbore, 3.5 deep on MGN9 and 4.5 on MGN12 / MGN15, for M3 socket heads. Pitch 20 (MGN9), 25 (MGN12), 40 (MGN15).",
   "Holes are centred along each rail: the end hole sits 12.5 from the end on every MGN12; 5 (150) or 10 on the MGN9; 15, 20, 10 and 20 on the MGN15 150–400.",
   "Rail section drawn as a plain rectangle; the carriage files have the rail channel at this section."
  ],
  "table": {
   "columns": [
    "rail",
    "W",
    "H",
    "pitch",
    "hole",
    "counterbore",
    "end hole (150/200/300/400)"
   ],
   "rows": [
    [
     "MGN9",
     9,
     6.5,
     20,
     "Ø3.5",
     "Ø6 × 3.5",
     "5 / 10 / 10 / 10"
    ],
    [
     "MGN12",
     12,
     8,
     25,
     "Ø3.5",
     "Ø6 × 4.5",
     "12.5 / 12.5 / 12.5 / 12.5"
    ],
    [
     "MGN15",
     15,
     10,
     40,
     "Ø3.5",
     "Ø6 × 4.5",
     "15 / 20 / 10 / 20"
    ]
   ]
  }
 },
 "sheet_text": "MGN9, MGN12 and MGN15 rails, 150 to 400 mm — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/mgn-rails/  (CC BY 4.0)\nBasis: HIWIN MGN catalogue rail section, hole pitch and counterbore (other brands match)\nCatalog version: 2026-10-20\n\nSizes: see table below\n- Rail section W × H: MGN9 9 × 6.5; MGN12 12 × 8; MGN15 15 × 10. Lengths 150, 200, 300, 400.\n- Holes Ø3.5 through with a Ø6 counterbore, 3.5 deep on MGN9 and 4.5 on MGN12 / MGN15, for M3 socket heads. Pitch 20 (MGN9), 25 (MGN12), 40 (MGN15).\n- Holes are centred along each rail: the end hole sits 12.5 from the end on every MGN12; 5 (150) or 10 on the MGN9; 15, 20, 10 and 20 on the MGN15 150–400.\n- Rail section drawn as a plain rectangle; the carriage files have the rail channel at this section.\n\nrail  W  H  pitch  hole  counterbore  end hole (150/200/300/400)\nMGN9  9  6.5  20  Ø3.5  Ø6 × 3.5  5 / 10 / 10 / 10\nMGN12  12  8  25  Ø3.5  Ø6 × 4.5  12.5 / 12.5 / 12.5 / 12.5\nMGN15  15  10  40  Ø3.5  Ø6 × 4.5  15 / 20 / 10 / 20\n\nFiles elsewhere (not hosted by Xem Studio; license as stated by the publisher):\n- HIWIN: MGN series linear guideway catalogue — PDF, STEP — HIWIN site terms [verify license at link] — https://www.hiwin.com/en/products/linear-guideways/mgn-mgw-series\n- Wikipedia: Linear-motion bearing — web — CC BY-SA 4.0 (text) — https://en.wikipedia.org/wiki/Linear-motion_bearing\n\nFree files (CC BY 4.0, Xem Studio; STEP + STL, 12 parts): https://xemstudio.com/files/hardware/mgn-rails/index.json\nAPI: https://xemstudio.com/api/geometry?object=mgn-rails\n",
 "sources": [
  {
   "publisher": "HIWIN",
   "title": "MGN series linear guideway catalogue",
   "url": "https://www.hiwin.com/en/products/linear-guideways/mgn-mgw-series",
   "formats": [
    "PDF",
    "STEP"
   ],
   "license": "HIWIN site terms",
   "license_verified": false,
   "hosted": false
  },
  {
   "publisher": "Wikipedia",
   "title": "Linear-motion bearing",
   "url": "https://en.wikipedia.org/wiki/Linear-motion_bearing",
   "formats": [
    "web"
   ],
   "license": "CC BY-SA 4.0 (text)",
   "license_verified": true,
   "hosted": false
  }
 ],
 "xem": {
  "status": "free-files",
  "sheet_free": true,
  "mesh_price_usd": null,
  "step_price_usd": null,
  "tolerance_mm": null
 },
 "related": [
  "mgn-carriages",
  "socket-head-cap-screws-metric",
  "2020-extrusion",
  "t8-lead-screw"
 ],
 "fits": [
  {
   "role": "Goes in or on",
   "items": [
    {
     "slug": "2020-extrusion",
     "why": "screwed to the extrusion face"
    }
   ]
  },
  {
   "role": "Connects to",
   "items": [
    {
     "slug": "mgn-carriages",
     "why": "carriage channel at the rail section"
    }
   ]
  },
  {
   "role": "Also needed",
   "items": [
    {
     "slug": "socket-head-cap-screws-metric",
     "why": "M3 in the counterbores"
    }
   ]
  }
 ],
 "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": "rail holes",
   "exact": "Ø3.5 through, counterbore Ø6 × 3.5 (MGN9) / 4.5",
   "mates": "M3 socket head screws",
   "fit": "designed",
   "files": "all"
  },
  {
   "feature": "carriage holes",
   "exact": "M3 (Ø3 major)",
   "mates": "M3 screws",
   "fit": "designed",
   "files": "all"
  },
  {
   "feature": "rail section",
   "exact": "9 × 6.5 / 12 × 8 / 15 × 10",
   "mates": "carriage channel",
   "fit": "designed",
   "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": "What is the hole spacing on an MGN12 rail?",
   "a": "25 mm, Ø3.5 holes with a Ø6 counterbore 4.5 deep for M3. MGN9 is 20 (counterbore 3.5 deep), MGN15 40."
  },
  {
   "q": "What size is an MGN12 rail?",
   "a": "12 wide × 8 tall."
  }
 ],
 "files_license": null,
 "offers": [
  {
   "file": "mgn9-rail-150",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/mgn-linear-rails/mgn9-rail-150.step",
   "stl": "https://xemstudio.com/files/hardware/mgn-linear-rails/mgn9-rail-150.stl",
   "note": "MGN9 rail 150 mm, 20 mm hole pitch"
  },
  {
   "file": "mgn9-rail-200",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/mgn-linear-rails/mgn9-rail-200.step",
   "stl": "https://xemstudio.com/files/hardware/mgn-linear-rails/mgn9-rail-200.stl",
   "note": "MGN9 rail 200 mm, 20 mm hole pitch"
  },
  {
   "file": "mgn9-rail-300",
   "formats": [
    "step",
    "stl"
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   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/mgn-linear-rails/mgn9-rail-300.step",
   "stl": "https://xemstudio.com/files/hardware/mgn-linear-rails/mgn9-rail-300.stl",
   "note": "MGN9 rail 300 mm, 20 mm hole pitch"
  },
  {
   "file": "mgn9-rail-400",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/mgn-linear-rails/mgn9-rail-400.step",
   "stl": "https://xemstudio.com/files/hardware/mgn-linear-rails/mgn9-rail-400.stl",
   "note": "MGN9 rail 400 mm, 20 mm hole pitch"
  },
  {
   "file": "mgn12-rail-150",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/mgn-linear-rails/mgn12-rail-150.step",
   "stl": "https://xemstudio.com/files/hardware/mgn-linear-rails/mgn12-rail-150.stl",
   "note": "MGN12 rail 150 mm, 25 mm hole pitch"
  },
  {
   "file": "mgn12-rail-200",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/mgn-linear-rails/mgn12-rail-200.step",
   "stl": "https://xemstudio.com/files/hardware/mgn-linear-rails/mgn12-rail-200.stl",
   "note": "MGN12 rail 200 mm, 25 mm hole pitch"
  },
  {
   "file": "mgn12-rail-300",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/mgn-linear-rails/mgn12-rail-300.step",
   "stl": "https://xemstudio.com/files/hardware/mgn-linear-rails/mgn12-rail-300.stl",
   "note": "MGN12 rail 300 mm, 25 mm hole pitch"
  },
  {
   "file": "mgn12-rail-400",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/mgn-linear-rails/mgn12-rail-400.step",
   "stl": "https://xemstudio.com/files/hardware/mgn-linear-rails/mgn12-rail-400.stl",
   "note": "MGN12 rail 400 mm, 25 mm hole pitch"
  },
  {
   "file": "mgn15-rail-150",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/mgn-linear-rails/mgn15-rail-150.step",
   "stl": "https://xemstudio.com/files/hardware/mgn-linear-rails/mgn15-rail-150.stl",
   "note": "MGN15 rail 150 mm, 40 mm hole pitch"
  },
  {
   "file": "mgn15-rail-200",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/mgn-linear-rails/mgn15-rail-200.step",
   "stl": "https://xemstudio.com/files/hardware/mgn-linear-rails/mgn15-rail-200.stl",
   "note": "MGN15 rail 200 mm, 40 mm hole pitch"
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  {
   "file": "mgn15-rail-300",
   "formats": [
    "step",
    "stl"
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   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/mgn-linear-rails/mgn15-rail-300.step",
   "stl": "https://xemstudio.com/files/hardware/mgn-linear-rails/mgn15-rail-300.stl",
   "note": "MGN15 rail 300 mm, 40 mm hole pitch"
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  {
   "file": "mgn15-rail-400",
   "formats": [
    "step",
    "stl"
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   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/mgn-linear-rails/mgn15-rail-400.step",
   "stl": "https://xemstudio.com/files/hardware/mgn-linear-rails/mgn15-rail-400.stl",
   "note": "MGN15 rail 400 mm, 40 mm hole pitch"
  }
 ],
 "markdown": "https://xemstudio.com/objects/mgn-rails/index.md"
}