{
 "version": "2026-10-20",
 "license": "Dimension sheets: CC BY 4.0. Standard and published-size files: CC BY 4.0. Xem Studio's own designs (files_license = Xem Studio Design License): free to use and sell things from, not to redistribute as files — https://xemstudio.com/license/. Other publishers' files: their own license, linked beside them.",
 "slug": "cross-dowels-barrel-nuts-m4-m10",
 "name": "Cross dowels / barrel nuts M4–M10 (furniture bolt nuts): barrel diameter and length by thread",
 "kind": "standard",
 "category": "Hardware",
 "group": "Fasteners",
 "year": null,
 "question": "What are the diameter and length of an M6 cross dowel (barrel nut) for a bed or table bolt?",
 "tags": [
  "cross dowel",
  "barrel nut",
  "cross-dowel nut",
  "furniture barrel nut",
  "bed bolt nut",
  "ikea barrel nut",
  "dowel nut",
  "m6 barrel nut",
  "cross dowel nut",
  "furniture connector bolt",
  "tool"
 ],
 "aliases": [
  "m6 cross dowel dimensions",
  "m6 barrel nut size",
  "cross dowel 10 mm diameter",
  "m8 barrel nut dimensions",
  "cross dowel nut sizes",
  "barrel nut 10 x 16",
  "m6 cross dowel 15 mm",
  "m4 barrel nut cross dowel",
  "ikea cross dowel size",
  "furniture barrel nut hole size",
  "m10 cross dowel nut size",
  "cross dowel l1 l2"
 ],
 "overall_mm": {
  "length": null,
  "width": null,
  "height": null
 },
 "official_cad": false,
 "xem_status": "not-scanned",
 "les": false,
 "free_files": 0,
 "url": "https://xemstudio.com/objects/cross-dowels-barrel-nuts-m4-m10/",
 "sheet_txt": "https://xemstudio.com/objects/cross-dowels-barrel-nuts-m4-m10/sheet.txt",
 "sheet": {
  "basis": "Essentra Components' cross dowel page (four items) and Fastenright's cross dowel table (52 rows, M4 to M10); numbers only",
  "overall_mm": {
   "length": null,
   "width": null,
   "height": null
  },
  "notes": [
   "Millimetres. A cross dowel (barrel nut, cross-dowel nut) is a cylinder with a threaded hole across its diameter, set in a bored hole in the wood so a bolt in the end of the board threads into it. Essentra lists M6 at Ø10 × 13, 16 and 20 mm (zinc alloy, crossed drive) and M8 at Ø12 × 18 mm (steel, slotted): thread size, outside diameter (barrel diameter), overall length, material and drive; no hole sizes.",
   "Fastenright's table has four columns: thread diameter, barrel diameter, L1 and L2, all mm. It does not define L1 and L2. Fastenright's L1 values include every Essentra overall length (M6 × Ø10: 13, 16, 20; M8 × Ø12: 18), so L1 reads as the overall length; L2 is usually half of L1 (for example 16 / 8, 20 / 10, 30 / 15) but not always (M6 × 10 × 16 has L2 5, 6 and 8; M6 × 10 × 12.5 has 5; M6 × 10 × 25 has 12.5 and 10), so it is not defined here and may be the cross-hole position from one end. The existing page cross-dowel-m6 carries one retailer's M6 × Ø10 × 30 barrel nut, which Fastenright lists with L2 15 and 10.",
   "The standard drill-hole sizes for the bore the barrel sits in and the bolt hole are not printed on either page; furniture makers publish those in their drilling jigs, and none was read here. No file: the cross-hole position and thread depth are not defined in the sheets, so no model is drawn.",
   "Tee nuts for wood: tee-nuts-for-wood-3-4-prong. Flat-pack bolts are usually M6 with a hex or Allen head; see hex-head-screws-metric and socket-head-cap-screws-metric."
  ],
  "table": {
   "columns": [
    "source",
    "thread",
    "barrel diameter (mm)",
    "length / L1 (mm)",
    "L2 (mm, as printed)",
    "note"
   ],
   "rows": [
    [
     "Essentra",
     "M6",
     "10",
     "13",
     "—",
     "zinc alloy, crossed (Pozidriv-type)"
    ],
    [
     "Essentra",
     "M6",
     "10",
     "16",
     "—",
     "zinc alloy, crossed"
    ],
    [
     "Essentra",
     "M6",
     "10",
     "20",
     "—",
     "zinc alloy, crossed"
    ],
    [
     "Essentra",
     "M8",
     "12",
     "18",
     "—",
     "steel, slotted"
    ],
    [
     "Fastenright",
     "M4",
     "8",
     "12",
     "6",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M4",
     "8",
     "16",
     "8",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M4",
     "8",
     "20",
     "10",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M5",
     "8",
     "12",
     "6",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M5",
     "8",
     "16",
     "8",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M5",
     "8",
     "20",
     "10",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M6",
     "10",
     "12",
     "6",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M6",
     "10",
     "12.5",
     "5",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M6",
     "10",
     "13",
     "5",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M6",
     "10",
     "14",
     "5",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M6",
     "10",
     "14",
     "6",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M6",
     "10",
     "14",
     "7",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M6",
     "10",
     "15",
     "6",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M6",
     "10",
     "15",
     "7.5",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M6",
     "10",
     "16",
     "5",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M6",
     "10",
     "16",
     "6",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M6",
     "10",
     "16",
     "8",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M6",
     "10",
     "17",
     "6",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M6",
     "10",
     "18",
     "6",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M6",
     "10",
     "18",
     "9",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M6",
     "10",
     "19",
     "9.5",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M6",
     "10",
     "20",
     "10",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M6",
     "10",
     "22",
     "11",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M6",
     "10",
     "25",
     "12.5",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M6",
     "10",
     "25",
     "10",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M6",
     "10",
     "30",
     "15",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M6",
     "10",
     "30",
     "10",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M6",
     "10",
     "35",
     "17.5",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M6",
     "10",
     "35",
     "10",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M6",
     "10",
     "40",
     "20",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M6",
     "12",
     "12",
     "5",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M6",
     "12",
     "16",
     "6",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M6",
     "12",
     "16",
     "8",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M6",
     "16",
     "12",
     "5",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M8",
     "12",
     "12",
     "6",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M8",
     "12",
     "14",
     "7",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M8",
     "12",
     "16",
     "8",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M8",
     "12",
     "18",
     "9",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M8",
     "12",
     "20",
     "10",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M8",
     "12",
     "20",
     "8",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M8",
     "12",
     "25",
     "12.5",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M8",
     "12",
     "30",
     "15",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M8",
     "12",
     "35",
     "17.5",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M8",
     "12",
     "40",
     "20",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M8",
     "12",
     "45",
     "22.5",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M8",
     "12",
     "50",
     "25",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M8",
     "12",
     "60",
     "30",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M10",
     "16",
     "20",
     "10",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M10",
     "16",
     "25",
     "12.5",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M10",
     "16",
     "30",
     "15",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M10",
     "16",
     "40",
     "20",
     "L1 and L2 as printed (not defined on the page)"
    ],
    [
     "Fastenright",
     "M10",
     "16",
     "50",
     "25",
     "L1 and L2 as printed (not defined on the page)"
    ]
   ]
  }
 },
 "sheet_text": "Cross dowels / barrel nuts M4–M10 (furniture bolt nuts): barrel diameter and length by thread — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/cross-dowels-barrel-nuts-m4-m10/  (sheet CC BY 4.0)\nBasis: Essentra Components' cross dowel page (four items) and Fastenright's cross dowel table (52 rows, M4 to M10); numbers only\nCatalog version: 2026-10-20\n\nSizes: see table below\n- Millimetres. A cross dowel (barrel nut, cross-dowel nut) is a cylinder with a threaded hole across its diameter, set in a bored hole in the wood so a bolt in the end of the board threads into it. Essentra lists M6 at Ø10 × 13, 16 and 20 mm (zinc alloy, crossed drive) and M8 at Ø12 × 18 mm (steel, slotted): thread size, outside diameter (barrel diameter), overall length, material and drive; no hole sizes.\n- Fastenright's table has four columns: thread diameter, barrel diameter, L1 and L2, all mm. It does not define L1 and L2. Fastenright's L1 values include every Essentra overall length (M6 × Ø10: 13, 16, 20; M8 × Ø12: 18), so L1 reads as the overall length; L2 is usually half of L1 (for example 16 / 8, 20 / 10, 30 / 15) but not always (M6 × 10 × 16 has L2 5, 6 and 8; M6 × 10 × 12.5 has 5; M6 × 10 × 25 has 12.5 and 10), so it is not defined here and may be the cross-hole position from one end. The existing page cross-dowel-m6 carries one retailer's M6 × Ø10 × 30 barrel nut, which Fastenright lists with L2 15 and 10.\n- The standard drill-hole sizes for the bore the barrel sits in and the bolt hole are not printed on either page; furniture makers publish those in their drilling jigs, and none was read here. No file: the cross-hole position and thread depth are not defined in the sheets, so no model is drawn.\n- Tee nuts for wood: tee-nuts-for-wood-3-4-prong. Flat-pack bolts are usually M6 with a hex or Allen head; see hex-head-screws-metric and socket-head-cap-screws-metric.\n\nsource  thread  barrel diameter (mm)  length / L1 (mm)  L2 (mm, as printed)  note\nEssentra  M6  10  13  —  zinc alloy, crossed (Pozidriv-type)\nEssentra  M6  10  16  —  zinc alloy, crossed\nEssentra  M6  10  20  —  zinc alloy, crossed\nEssentra  M8  12  18  —  steel, slotted\nFastenright  M4  8  12  6  L1 and L2 as printed (not defined on the page)\nFastenright  M4  8  16  8  L1 and L2 as printed (not defined on the page)\nFastenright  M4  8  20  10  L1 and L2 as printed (not defined on the page)\nFastenright  M5  8  12  6  L1 and L2 as printed (not defined on the page)\nFastenright  M5  8  16  8  L1 and L2 as printed (not defined on the page)\nFastenright  M5  8  20  10  L1 and L2 as printed (not defined on the page)\nFastenright  M6  10  12  6  L1 and L2 as printed (not defined on the page)\nFastenright  M6  10  12.5  5  L1 and L2 as printed (not defined on the page)\nFastenright  M6  10  13  5  L1 and L2 as printed (not defined on the page)\nFastenright  M6  10  14  5  L1 and L2 as printed (not defined on the page)\nFastenright  M6  10  14  6  L1 and L2 as printed (not defined on the page)\nFastenright  M6  10  14  7  L1 and L2 as printed (not defined on the page)\nFastenright  M6  10  15  6  L1 and L2 as printed (not defined on the page)\nFastenright  M6  10  15  7.5  L1 and L2 as printed (not defined on the page)\nFastenright  M6  10  16  5  L1 and L2 as printed (not defined on the page)\nFastenright  M6  10  16  6  L1 and L2 as printed (not defined on the page)\nFastenright  M6  10  16  8  L1 and L2 as printed (not defined on the page)\nFastenright  M6  10  17  6  L1 and L2 as printed (not defined on the page)\nFastenright  M6  10  18  6  L1 and L2 as printed (not defined on the page)\nFastenright  M6  10  18  9  L1 and L2 as printed (not defined on the page)\nFastenright  M6  10  19  9.5  L1 and L2 as printed (not defined on the page)\nFastenright  M6  10  20  10  L1 and L2 as printed (not defined on the page)\nFastenright  M6  10  22  11  L1 and L2 as printed (not defined on the page)\nFastenright  M6  10  25  12.5  L1 and L2 as printed (not defined on the page)\nFastenright  M6  10  25  10  L1 and L2 as printed (not defined on the page)\nFastenright  M6  10  30  15  L1 and L2 as printed (not defined on the page)\nFastenright  M6  10  30  10  L1 and L2 as printed (not defined on the page)\nFastenright  M6  10  35  17.5  L1 and L2 as printed (not defined on the page)\nFastenright  M6  10  35  10  L1 and L2 as printed (not defined on the page)\nFastenright  M6  10  40  20  L1 and L2 as printed (not defined on the page)\nFastenright  M6  12  12  5  L1 and L2 as printed (not defined on the page)\nFastenright  M6  12  16  6  L1 and L2 as printed (not defined on the page)\nFastenright  M6  12  16  8  L1 and L2 as printed (not defined on the page)\nFastenright  M6  16  12  5  L1 and L2 as printed (not defined on the page)\nFastenright  M8  12  12  6  L1 and L2 as printed (not defined on the page)\nFastenright  M8  12  14  7  L1 and L2 as printed (not defined on the page)\nFastenright  M8  12  16  8  L1 and L2 as printed (not defined on the page)\nFastenright  M8  12  18  9  L1 and L2 as printed (not defined on the page)\nFastenright  M8  12  20  10  L1 and L2 as printed (not defined on the page)\nFastenright  M8  12  20  8  L1 and L2 as printed (not defined on the page)\nFastenright  M8  12  25  12.5  L1 and L2 as printed (not defined on the page)\nFastenright  M8  12  30  15  L1 and L2 as printed (not defined on the page)\nFastenright  M8  12  35  17.5  L1 and L2 as printed (not defined on the page)\nFastenright  M8  12  40  20  L1 and L2 as printed (not defined on the page)\nFastenright  M8  12  45  22.5  L1 and L2 as printed (not defined on the page)\nFastenright  M8  12  50  25  L1 and L2 as printed (not defined on the page)\nFastenright  M8  12  60  30  L1 and L2 as printed (not defined on the page)\nFastenright  M10  16  20  10  L1 and L2 as printed (not defined on the page)\nFastenright  M10  16  25  12.5  L1 and L2 as printed (not defined on the page)\nFastenright  M10  16  30  15  L1 and L2 as printed (not defined on the page)\nFastenright  M10  16  40  20  L1 and L2 as printed (not defined on the page)\nFastenright  M10  16  50  25  L1 and L2 as printed (not defined on the page)\n\nFiles elsewhere (not hosted by Xem Studio; license as stated by the publisher):\n- Essentra Components: Cross dowel barrel nuts: M6 13 / 16 / 20 mm and M8 18 mm, outside diameter 10 and 12 mm, overall length, material, drive — web — Maker catalogue page; numbers only — https://www.essentracomponents.com/en-gb/p/cross-dowel-barrel-nuts\n- Fastenright: Cross dowel barrel nuts: thread diameter, barrel diameter, L1 and L2 (not defined on the page), M4 to M10 — web — Maker catalogue page; numbers only — https://www.fastenright.com/general-fixings/cross-dowel-barrel-nut/ff04\n\nNo true-size file yet: the published figures do not fix the whole shape; a measured scan is planned.\nAPI: https://xemstudio.com/api/geometry?object=cross-dowels-barrel-nuts-m4-m10\n",
 "sources": [
  {
   "publisher": "Essentra Components",
   "title": "Cross dowel barrel nuts: M6 13 / 16 / 20 mm and M8 18 mm, outside diameter 10 and 12 mm, overall length, material, drive",
   "url": "https://www.essentracomponents.com/en-gb/p/cross-dowel-barrel-nuts",
   "formats": [
    "web"
   ],
   "license": "Maker catalogue page; numbers only",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "Fastenright",
   "title": "Cross dowel barrel nuts: thread diameter, barrel diameter, L1 and L2 (not defined on the page), M4 to M10",
   "url": "https://www.fastenright.com/general-fixings/cross-dowel-barrel-nut/ff04",
   "formats": [
    "web"
   ],
   "license": "Maker catalogue page; numbers only",
   "license_verified": true,
   "hosted": false
  }
 ],
 "xem": {
  "status": "not-scanned",
  "sheet_free": true,
  "mesh_price_usd": null,
  "step_price_usd": null,
  "tolerance_mm": null
 },
 "related": [
  "cross-dowel-m6",
  "tee-nuts-for-wood-3-4-prong",
  "hex-head-screws-metric",
  "socket-head-cap-screws-metric",
  "rivet-nuts-flat-head"
 ],
 "fits": [],
 "dimensions": "exact (nominal, no tolerance added)",
 "dimension_rule": "All geometry on Xem Studio is exact (nominal, true size) with no tolerance added. 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. Typical accuracy by process and ISO 286 fits: https://xemstudio.com/tolerances/",
 "mating": [],
 "faq": [
  {
   "q": "What size is an M6 cross dowel?",
   "a": "Barrel diameter 10 mm; lengths 12 to 40 mm in Fastenright's table, 13, 16 and 20 mm at Essentra. M6 Ø12 and Ø16 barrels also exist."
  },
  {
   "q": "What is the barrel diameter of an M8 cross dowel?",
   "a": "12 mm (Essentra and Fastenright), in lengths 12 to 60 mm at Fastenright."
  },
  {
   "q": "What is L2 in a cross dowel table?",
   "a": "Fastenright does not define it; it is often half of L1 but not always, so check the maker's drawing."
  }
 ],
 "files_license": null,
 "offers": [],
 "markdown": "https://xemstudio.com/objects/cross-dowels-barrel-nuts-m4-m10/index.md"
}