{
 "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": "t-slot-end-caps",
 "name": "End caps for 20, 30, 40 and 10-series extrusion (1, 2 and 4 cells)",
 "kind": "hardware",
 "category": "Hardware",
 "group": "Framing",
 "year": null,
 "question": "What size end cap for 2020 extrusion?",
 "tags": [
  "end cap",
  "extrusion",
  "2020",
  "t-slot",
  "stirling",
  "long earth society"
 ],
 "aliases": [
  "2020 end cap stl",
  "extrusion end cap",
  "2040 end cap",
  "t slot end cover",
  "8020 end cap"
 ],
 "overall_mm": {
  "length": null,
  "width": null,
  "height": null
 },
 "official_cad": false,
 "xem_status": "free-files",
 "les": true,
 "free_files": 6,
 "url": "https://xemstudio.com/objects/t-slot-end-caps/",
 "sheet_txt": "https://xemstudio.com/objects/t-slot-end-caps/sheet.txt",
 "sheet": {
  "basis": "Cap = profile outline (exact), 3 thick; pins = profile centre bore (exact) × 8 long, one per cell",
  "overall_mm": {
   "length": null,
   "width": null,
   "height": null
  },
  "notes": [
   "Each cap is a 3 mm plate at the exact profile outline with R1.5 corners and one pin per cell, the profile's centre-bore diameter by 8 mm long with a 0.8 mm chamfer; 11 mm overall.",
   "Pins: Ø4.2 on 20-series, Ø6.8 on 30 and 40, Ø5.1 on 10-series.",
   "Sizes: 20-series 1 × 1 (20 × 20), 2 × 1 (40 × 20), 4 × 1 (80 × 20); 30-series 30 × 30; 40-series 40 × 40; 10-series 25.4 × 25.4.",
   "The pins press into the centre bores (press, see Mating features)."
  ],
  "table": {
   "columns": [
    "file",
    "outline_mm",
    "pins",
    "pin_dia_mm"
   ],
   "rows": [
    [
     "end-cap-20-1x1",
     "20 × 20",
     1,
     4.2
    ],
    [
     "end-cap-20-2x1",
     "40 × 20",
     2,
     4.2
    ],
    [
     "end-cap-20-4x1",
     "80 × 20",
     4,
     4.2
    ],
    [
     "end-cap-30-1x1",
     "30 × 30",
     1,
     6.8
    ],
    [
     "end-cap-40-1x1",
     "40 × 40",
     1,
     6.8
    ],
    [
     "end-cap-10in-1x1",
     "25.4 × 25.4",
     1,
     5.1
    ]
   ]
  }
 },
 "sheet_text": "End caps for 20, 30, 40 and 10-series extrusion (1, 2 and 4 cells) — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/t-slot-end-caps/  (CC BY 4.0)\nBasis: Cap = profile outline (exact), 3 thick; pins = profile centre bore (exact) × 8 long, one per cell\nCatalog version: 2026-10-20\n\nSizes: see table below\n- Each cap is a 3 mm plate at the exact profile outline with R1.5 corners and one pin per cell, the profile's centre-bore diameter by 8 mm long with a 0.8 mm chamfer; 11 mm overall.\n- Pins: Ø4.2 on 20-series, Ø6.8 on 30 and 40, Ø5.1 on 10-series.\n- Sizes: 20-series 1 × 1 (20 × 20), 2 × 1 (40 × 20), 4 × 1 (80 × 20); 30-series 30 × 30; 40-series 40 × 40; 10-series 25.4 × 25.4.\n- The pins press into the centre bores (press, see Mating features).\n\nfile  outline_mm  pins  pin_dia_mm\nend-cap-20-1x1  20 × 20  1  4.2\nend-cap-20-2x1  40 × 20  2  4.2\nend-cap-20-4x1  80 × 20  4  4.2\nend-cap-30-1x1  30 × 30  1  6.8\nend-cap-40-1x1  40 × 40  1  6.8\nend-cap-10in-1x1  25.4 × 25.4  1  5.1\n\nFiles elsewhere (not hosted by Xem Studio; license as stated by the publisher):\n- Wikipedia: T-slot nut — web — CC BY-SA 4.0 (text) — https://en.wikipedia.org/wiki/T-slot_nut\n- OpenBuilds: Tee nuts and brackets for V-slot — web, STEP — OpenBuilds site [verify license at link] — https://openbuildspartstore.com/\n- Long Earth Society: Engine and rig builds on extrusion frames — web, video — LES site — https://longearthsociety.com/engineering/\n\nFree files (CC BY 4.0, Xem Studio; STEP + STL, 6 parts): https://xemstudio.com/files/hardware/t-slot-end-caps/index.json\nAPI: https://xemstudio.com/api/geometry?object=t-slot-end-caps\n",
 "sources": [
  {
   "publisher": "Wikipedia",
   "title": "T-slot nut",
   "url": "https://en.wikipedia.org/wiki/T-slot_nut",
   "formats": [
    "web"
   ],
   "license": "CC BY-SA 4.0 (text)",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "OpenBuilds",
   "title": "Tee nuts and brackets for V-slot",
   "url": "https://openbuildspartstore.com/",
   "formats": [
    "web",
    "STEP"
   ],
   "license": "OpenBuilds site",
   "license_verified": false,
   "hosted": false
  },
  {
   "publisher": "Long Earth Society",
   "title": "Engine and rig builds on extrusion frames",
   "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": [
  "t-slot-feet",
  "t-slot-covers",
  "t-slot-extrusions",
  "2020-extrusion",
  "button-head-screws-metric"
 ],
 "fits": [
  {
   "role": "Goes in or on",
   "items": [
    {
     "slug": "t-slot-extrusions",
     "why": "pins in the profile centre bores (press)"
    }
   ]
  },
  {
   "role": "Alternatives",
   "items": [
    {
     "slug": "t-slot-feet",
     "why": "a foot instead of a flat cap"
    }
   ]
  }
 ],
 "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": "bracket / gusset / plate screw holes",
   "exact": "Ø5.5 / 6.6 / 9.0 / 7.14",
   "mates": "M5 / M6 / M8 / 1/4-20 clearance",
   "fit": "designed",
   "files": "all"
  },
  {
   "feature": "end-cap pins",
   "exact": "centre bore (4.2 / 6.8 / 5.1)",
   "mates": "profile centre bore",
   "fit": "press",
   "files": "end-cap-"
  },
  {
   "feature": "end-cap outline",
   "exact": "profile outline",
   "mates": "profile end face",
   "fit": "designed",
   "files": "end-cap-"
  }
 ],
 "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 size pin for a 2020 end cap?",
   "a": "Ø4.2, the profile's centre bore, 8 mm long."
  },
  {
   "q": "Is there a cap for 2040 and 2080?",
   "a": "Yes: end-cap-20-2x1 (40 × 20) and end-cap-20-4x1 (80 × 20)."
  }
 ],
 "files_license": null,
 "offers": [
  {
   "file": "end-cap-20-1x1",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/t-slot-brackets-and-nuts/end-cap-20-1x1.step",
   "stl": "https://xemstudio.com/files/hardware/t-slot-brackets-and-nuts/end-cap-20-1x1.stl",
   "note": "20-series end cap, 1 × 1 cells, pins Ø4.2 (the centre bore, exact) press into the bores"
  },
  {
   "file": "end-cap-20-2x1",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/t-slot-brackets-and-nuts/end-cap-20-2x1.step",
   "stl": "https://xemstudio.com/files/hardware/t-slot-brackets-and-nuts/end-cap-20-2x1.stl",
   "note": "20-series end cap, 2 × 1 cells, pins Ø4.2 (the centre bore, exact) press into the bores"
  },
  {
   "file": "end-cap-20-4x1",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/t-slot-brackets-and-nuts/end-cap-20-4x1.step",
   "stl": "https://xemstudio.com/files/hardware/t-slot-brackets-and-nuts/end-cap-20-4x1.stl",
   "note": "20-series end cap, 4 × 1 cells, pins Ø4.2 (the centre bore, exact) press into the bores"
  },
  {
   "file": "end-cap-30-1x1",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/t-slot-brackets-and-nuts/end-cap-30-1x1.step",
   "stl": "https://xemstudio.com/files/hardware/t-slot-brackets-and-nuts/end-cap-30-1x1.stl",
   "note": "30-series end cap, 1 × 1 cells, pins Ø6.8 (the centre bore, exact) press into the bores"
  },
  {
   "file": "end-cap-40-1x1",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/t-slot-brackets-and-nuts/end-cap-40-1x1.step",
   "stl": "https://xemstudio.com/files/hardware/t-slot-brackets-and-nuts/end-cap-40-1x1.stl",
   "note": "40-series end cap, 1 × 1 cells, pins Ø6.8 (the centre bore, exact) press into the bores"
  },
  {
   "file": "end-cap-10in-1x1",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/t-slot-brackets-and-nuts/end-cap-10in-1x1.step",
   "stl": "https://xemstudio.com/files/hardware/t-slot-brackets-and-nuts/end-cap-10in-1x1.stl",
   "note": "10in-series end cap, 1 × 1 cells, pins Ø5.1 (the centre bore, exact) press into the bores"
  }
 ],
 "markdown": "https://xemstudio.com/objects/t-slot-end-caps/index.md"
}