{
 "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": "4040-aluminum-extrusion",
 "name": "4040 aluminum extrusion, 10 mm slot (40-series)",
 "kind": "hardware",
 "category": "Hardware",
 "group": "Framing",
 "year": null,
 "question": "What are the exact dimensions of 4040 aluminum extrusion?",
 "tags": [
  "extrusion",
  "t-slot",
  "aluminum extrusion",
  "frame",
  "4040",
  "40-series"
 ],
 "aliases": [
  "4040 extrusion step",
  "4040 extrusion dxf",
  "4040 extrusion dimensions",
  "4040 aluminum extrusion cad",
  "40x40 extrusion profile",
  "4040 t slot profile",
  "4040 profile 10 mm slot",
  "4040 b-type extrusion"
 ],
 "overall_mm": {
  "length": null,
  "width": 40,
  "height": 40
 },
 "official_cad": false,
 "xem_status": "free-files",
 "les": false,
 "free_files": 2,
 "url": "https://xemstudio.com/objects/4040-aluminum-extrusion/",
 "sheet_txt": "https://xemstudio.com/objects/4040-aluminum-extrusion/sheet.txt",
 "sheet": {
  "basis": "Misumi 8 series, 10 mm slot, from Misumi's dimensioned drawing of this profile; every slot, lip, cavity, bore and outline number is the drawing's",
  "overall_mm": {
   "length": null,
   "width": 40,
   "height": 40
  },
  "notes": [
   "4040 aluminum extrusion, 10 mm slot (40-series): 40 × 40 mm, 4 slots on a 40 mm pitch (Misumi 8 series, 10 mm slot). Source: Misumi's dimensioned drawing of this profile. Files: STEP and STL at 100, 1000 mm with square ends, and a DXF of the exact cross-section (mm), the master to extrude to any length. The section is centred on the origin and extruded along +Z from z = 0.",
   "Slot: opening 10 mm, lip 5.5 mm thick at the opening, cavity 20 mm wide under the lips, 12.5 mm from the face to the cavity floor. Centre bore Ø10.5 mm per cell (the largest thread whose tap drill fits inside: M12, 10.2 mm).",
   "Cavity side walls: the drawing gives the cavity width (20 mm) and depths but not the web thickness, so the side walls run at 45° from the corner under each lip straight to the floor: the smallest cavity those numbers allow. The bar has at least the real metal there, and a part that fits this cavity fits the real one.",
   "Outer corners R3 (stated). Also drawn: 6 × 6 mm closed corner pockets 2 mm in from both faces (stated; their corner radii are not given, drawn square).",
   "Wrapping it: to make a part that fits around the bar, subtract the 1000 mm file (or extrude the DXF) from your solid; the outline is the drawing's 40 × 40 mm with no allowance, so open the pocket by your process's socket fit (see Mating features).",
   "Attachments: the 40-series (10 mm slot) T-nuts, end caps, feet, brackets, gussets, plates and slot covers are cut from these same numbers; the fit check (tools/asm_extrusion_fit.py) placed each one on this profile with zero overlap."
  ],
  "table": {
   "columns": [
    "feature",
    "size",
    "from"
   ],
   "rows": [
    [
     "outline",
     "40 × 40 mm, R3 corners",
     "drawing"
    ],
    [
     "slot pitch",
     "40 mm",
     "drawing"
    ],
    [
     "slot opening",
     "10 mm",
     "drawing"
    ],
    [
     "lip thickness at the opening",
     "5.5 mm",
     "drawing"
    ],
    [
     "cavity width under the lips",
     "20 mm",
     "drawing"
    ],
    [
     "face to cavity floor",
     "12.5 mm",
     "drawing"
    ],
    [
     "cavity depth under the lip (at the cavity wall)",
     "7 mm",
     "drawing"
    ],
    [
     "core between opposite floors",
     "15 mm",
     "pitch − 2 × face-to-floor"
    ],
    [
     "diagonal web",
     "not given (45° walls from the cavity corner)",
     "assumed minimum cavity"
    ],
    [
     "centre bore",
     "Ø10.5 mm × 1",
     "drawing"
    ],
    [
     "corner pockets",
     "6 × 6, 2 in from the faces",
     "drawing"
    ],
    [
     "cross-section area",
     "640 mm²",
     "maker's page"
    ],
    [
     "mass",
     "1.73 kg/m",
     "maker's page"
    ],
    [
     "Ix / Iy",
     "10.4 × 10⁴ / 10.4 × 10⁴ mm⁴",
     "maker's page"
    ],
    [
     "area of this model's section",
     "777.7 mm²",
     "computed from the DXF"
    ]
   ]
  }
 },
 "sheet_text": "4040 aluminum extrusion, 10 mm slot (40-series) — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/4040-aluminum-extrusion/  (CC BY 4.0)\nBasis: Misumi 8 series, 10 mm slot, from Misumi's dimensioned drawing of this profile; every slot, lip, cavity, bore and outline number is the drawing's\nCatalog version: 2026-10-20\n\nOverall (mm): width 40.0, height 40.0\n- 4040 aluminum extrusion, 10 mm slot (40-series): 40 × 40 mm, 4 slots on a 40 mm pitch (Misumi 8 series, 10 mm slot). Source: Misumi's dimensioned drawing of this profile. Files: STEP and STL at 100, 1000 mm with square ends, and a DXF of the exact cross-section (mm), the master to extrude to any length. The section is centred on the origin and extruded along +Z from z = 0.\n- Slot: opening 10 mm, lip 5.5 mm thick at the opening, cavity 20 mm wide under the lips, 12.5 mm from the face to the cavity floor. Centre bore Ø10.5 mm per cell (the largest thread whose tap drill fits inside: M12, 10.2 mm).\n- Cavity side walls: the drawing gives the cavity width (20 mm) and depths but not the web thickness, so the side walls run at 45° from the corner under each lip straight to the floor: the smallest cavity those numbers allow. The bar has at least the real metal there, and a part that fits this cavity fits the real one.\n- Outer corners R3 (stated). Also drawn: 6 × 6 mm closed corner pockets 2 mm in from both faces (stated; their corner radii are not given, drawn square).\n- Wrapping it: to make a part that fits around the bar, subtract the 1000 mm file (or extrude the DXF) from your solid; the outline is the drawing's 40 × 40 mm with no allowance, so open the pocket by your process's socket fit (see Mating features).\n- Attachments: the 40-series (10 mm slot) T-nuts, end caps, feet, brackets, gussets, plates and slot covers are cut from these same numbers; the fit check (tools/asm_extrusion_fit.py) placed each one on this profile with zero overlap.\n\nfeature  size  from\noutline  40 × 40 mm, R3 corners  drawing\nslot pitch  40 mm  drawing\nslot opening  10 mm  drawing\nlip thickness at the opening  5.5 mm  drawing\ncavity width under the lips  20 mm  drawing\nface to cavity floor  12.5 mm  drawing\ncavity depth under the lip (at the cavity wall)  7 mm  drawing\ncore between opposite floors  15 mm  pitch − 2 × face-to-floor\ndiagonal web  not given (45° walls from the cavity corner)  assumed minimum cavity\ncentre bore  Ø10.5 mm × 1  drawing\ncorner pockets  6 × 6, 2 in from the faces  drawing\ncross-section area  640 mm²  maker's page\nmass  1.73 kg/m  maker's page\nIx / Iy  10.4 × 10⁴ / 10.4 × 10⁴ mm⁴  maker's page\narea of this model's section  777.7 mm²  computed from the DXF\n\nFiles elsewhere (not hosted by Xem Studio; license as stated by the publisher):\n- Misumi: 40x40 Aluminum Extrusion - 8 Series, Base 40: product page with the cross-section drawing and section properties — web — Misumi site terms [verify license at link] — https://us.misumi-ec.com/vona2/detail/110302689860/\n- Misumi: 4040 dimensioned cross-section drawing — image — Misumi site terms [verify license at link] — https://us.misumi-ec.com/linked/item/10302689860/img/drw_01_004.gif\n\nFree files (CC BY 4.0, Xem Studio; STEP + STL, 2 parts): https://xemstudio.com/files/hardware/4040-aluminum-extrusion/index.json\nAPI: https://xemstudio.com/api/geometry?object=4040-aluminum-extrusion\n",
 "sources": [
  {
   "publisher": "Misumi",
   "title": "40x40 Aluminum Extrusion - 8 Series, Base 40: product page with the cross-section drawing and section properties",
   "url": "https://us.misumi-ec.com/vona2/detail/110302689860/",
   "formats": [
    "web"
   ],
   "license": "Misumi site terms",
   "license_verified": false,
   "hosted": false
  },
  {
   "publisher": "Misumi",
   "title": "4040 dimensioned cross-section drawing",
   "url": "https://us.misumi-ec.com/linked/item/10302689860/img/drw_01_004.gif",
   "formats": [
    "image"
   ],
   "license": "Misumi site terms",
   "license_verified": false,
   "hosted": false
  }
 ],
 "xem": {
  "status": "free-files",
  "sheet_free": true,
  "mesh_price_usd": null,
  "step_price_usd": null,
  "tolerance_mm": null
 },
 "related": [
  "4080-aluminum-extrusion",
  "8080-aluminum-extrusion",
  "slide-in-t-nuts",
  "drop-in-t-nuts",
  "t-slot-end-caps",
  "t-slot-corner-brackets",
  "button-head-screws-metric"
 ],
 "fits": [
  {
   "role": "Parts that fit it",
   "items": [
    {
     "slug": "slide-in-t-nuts",
     "why": "tongue in the opening, body in the cavity (slide)"
    },
    {
     "slug": "drop-in-t-nuts",
     "why": "drops through the opening, turns 90° in the cavity"
    },
    {
     "slug": "t-slot-corner-brackets",
     "why": "legs flat on two profile faces at 90°"
    },
    {
     "slug": "t-slot-gussets",
     "why": "legs on two profile faces in the inside corner"
    },
    {
     "slug": "t-slot-covers",
     "why": "stem in the slot opening, barb behind the lips"
    },
    {
     "slug": "t-slot-feet",
     "why": "profile end in the socket (socket fit)"
    },
    {
     "slug": "t-slot-joining-plates",
     "why": "holes over the slot centrelines on the profile pitch"
    },
    {
     "slug": "t-slot-end-caps",
     "why": "end-cap-40-1x1: pins in the centre bores (press)"
    }
   ]
  },
  {
   "role": "Alternatives",
   "items": [
    {
     "slug": "4080-aluminum-extrusion",
     "why": "same 40-series (10 mm slot) slot, 40 × 80 mm"
    },
    {
     "slug": "8080-aluminum-extrusion",
     "why": "same 40-series (10 mm slot) slot, 80 × 80 mm"
    }
   ]
  },
  {
   "role": "Also needed",
   "items": [
    {
     "slug": "button-head-screws-metric",
     "why": "M8 screws through brackets into the T-nuts"
    }
   ]
  }
 ],
 "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": "slot opening",
   "exact": "10",
   "mates": "T-nut tongue, slot-cover stem (40-series (10 mm slot))",
   "fit": "slide",
   "files": "all"
  },
  {
   "feature": "slot cavity",
   "exact": "20 wide under the lips, face to floor 12.5, lip 5.5",
   "mates": "T-nut body (slide-in, drop-in)",
   "fit": "slide",
   "files": "all"
  },
  {
   "feature": "centre bore",
   "exact": "Ø10.5",
   "mates": "M12 thread (tap drill 10.2); end-cap pin",
   "fit": "designed",
   "files": "all"
  },
  {
   "feature": "outline",
   "exact": "40 × 40, R3",
   "mates": "end-cap outline, foot socket, a pocket that wraps the bar",
   "fit": "socket",
   "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 slot size of 4040 extrusion?",
   "a": "Opening 10 mm, lip 5.5 mm, cavity 20 mm wide under the lips and 12.5 mm deep from the face to the floor, per Misumi 8 series, 10 mm slot's drawing."
  },
  {
   "q": "What T-nuts fit 4040 extrusion?",
   "a": "The 40-series (10 mm slot) nuts: slide-in (tnut-slide-40-m6, tnut-slide-40-m8) and drop-in versions, threaded M6, M8 as tap-drill holes, cut to this slot's exact space."
  },
  {
   "q": "Can I subtract this file to make a part that fits the extrusion exactly?",
   "a": "Yes: the outline is exactly 40 × 40 mm with R3 corners; extrude the DXF or subtract the 1000 mm STEP, then open the pocket by your fit."
  },
  {
   "q": "How heavy is 4040 extrusion?",
   "a": "1.73 kg/m, 640 mm² section, as Misumi states. This model's section is larger because closed hollows / cavity details the drawing leaves undimensioned are drawn filled; use the stated weight, not the model's volume."
  },
  {
   "q": "What in this model is not taken straight from the drawing?",
   "a": "Cavity side walls: the drawing gives the cavity width (20 mm) and depths but not the web thickness, so the side walls run at 45° from the corner under each lip straight to the floor: the smallest cavity those numbers allow. The bar has at least the real metal there, and a part that fits this cavity fits the real one."
  }
 ],
 "files_license": null,
 "offers": [
  {
   "file": "4040-100",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/4040-aluminum-extrusion/4040-100.step",
   "stl": "https://xemstudio.com/files/hardware/4040-aluminum-extrusion/4040-100.stl",
   "note": "4040 aluminum extrusion, 10 mm slot (40-series): 40 × 40 mm section, 100 mm long, square ends; DXF = the exact cross-section in mm"
  },
  {
   "file": "4040-1000",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/4040-aluminum-extrusion/4040-1000.step",
   "stl": "https://xemstudio.com/files/hardware/4040-aluminum-extrusion/4040-1000.stl",
   "note": "4040 aluminum extrusion, 10 mm slot (40-series): 40 × 40 mm section, 1000 mm long, square ends; DXF = the exact cross-section in mm"
  }
 ],
 "markdown": "https://xemstudio.com/objects/4040-aluminum-extrusion/index.md"
}