{
 "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": "print-in-place-captive-wheel-axle",
 "name": "Print-in-place: captive wheel on a printed axle (Ø40 × 12)",
 "kind": "hardware",
 "category": "3D printing",
 "group": "Print-in-place mechanisms",
 "year": null,
 "question": "How do you 3D print a wheel already on its axle?",
 "tags": [
  "3d printable",
  "print in place",
  "no assembly",
  "no supports",
  "mechanism",
  "stl",
  "step",
  "wheel",
  "axle"
 ],
 "aliases": [
  "print in place wheel",
  "print in place axle",
  "captive wheel 3d print",
  "wheel on axle stl",
  "print in place caster wheel"
 ],
 "overall_mm": {
  "length": 40,
  "width": 40,
  "height": 20
 },
 "official_cad": false,
 "xem_status": "free-files",
 "les": false,
 "free_files": 3,
 "url": "https://xemstudio.com/objects/print-in-place-captive-wheel-axle/",
 "sheet_txt": "https://xemstudio.com/objects/print-in-place-captive-wheel-axle/sheet.txt",
 "sheet": {
  "basis": "Xem Studio design: revolved profiles, axle and wheel coaxial, one designed running gap of 0.40 mm",
  "overall_mm": {
   "length": 40,
   "width": 40,
   "height": 20
  },
  "notes": [
   "3D print in place — prints already assembled, moving, in one job. Drawn at true size with no printer tolerance added; the 0.40 mm running gaps are part of the design.",
   "Running gap 0.40 mm per side, 0.80 mm on diameter — part of the design, drawn as is. On the 45° faces the same 0.40 mm is measured square to the face (0.57 mm along the axis).",
   "Bed: the wheel lies flat, axle vertical. Both bodies start on the bed: the wheel on its full face, the axle on its 45° base cone inside the wheel's lower counterbore.",
   "Support while printing: the wheel's lower counterbore narrows upward at 45° over the axle's base cone; the axle's head widens upward at 45° inside the wheel's upper counterbore; nothing in either body overhangs more than 45°.",
   "Captured by the two cones: the axle's base cone (Ø12) cannot pass up through the Ø8.8 bore and its head (Ø13) cannot pass down through it, so the wheel cannot leave the axle.",
   "Freeing it: hold the axle stem and turn the wheel a full turn each way; push the axle up and down once to break the first layer apart.",
   "Motion: continuous rotation about the axle; free end play 0.57 mm each way and 0.40 mm radial, both from the geometry. No stops.",
   "Mount: an M3 screw through the axle's Ø3.4 hole, or press the stem into a Ø13 socket."
  ],
  "table": {
   "columns": [
    "key",
    "value",
    "what"
   ],
   "rows": [
    [
     "gap_mm",
     0.4,
     "running gap per side on every moving interface (radial, axial, under captured parts) — part of the design, not a tolerance"
    ],
    [
     "wheel_d_mm",
     40,
     "wheel diameter"
    ],
    [
     "wheel_w_mm",
     12,
     "wheel thickness"
    ],
    [
     "pin_d_mm",
     8,
     "axle journal diameter"
    ],
    [
     "bore_d_mm",
     8.8,
     "wheel bore (journal + 2 × 0.40)"
    ],
    [
     "head_d_mm",
     13,
     "axle head diameter (45° cone from the journal)"
    ],
    [
     "base_d_mm",
     12,
     "axle base-cone diameter on the bed"
    ],
    [
     "axial_play_mm",
     0.57,
     "free end play each way from the drawn position (0.40 square to the 45° cones)"
    ],
    [
     "radial_play_mm",
     0.4,
     "free radial play"
    ],
    [
     "rotation_deg",
     "360 continuous",
     "wheel about the axle"
    ],
    [
     "stem_h_mm",
     8,
     "axle stem above the wheel"
    ],
    [
     "screw_hole_d_mm",
     3.4,
     "through hole along the axle (M3)"
    ]
   ]
  }
 },
 "sheet_text": "Print-in-place: captive wheel on a printed axle (Ø40 × 12) — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/print-in-place-captive-wheel-axle/  (sheet CC BY 4.0; files Xem Studio Design License, https://xemstudio.com/license/)\nBasis: Xem Studio design: revolved profiles, axle and wheel coaxial, one designed running gap of 0.40 mm\nCatalog version: 2026-10-20\n\nOverall (mm): length 40.0, width 40.0, height 20.0\n- 3D print in place — prints already assembled, moving, in one job. Drawn at true size with no printer tolerance added; the 0.40 mm running gaps are part of the design.\n- Running gap 0.40 mm per side, 0.80 mm on diameter — part of the design, drawn as is. On the 45° faces the same 0.40 mm is measured square to the face (0.57 mm along the axis).\n- Bed: the wheel lies flat, axle vertical. Both bodies start on the bed: the wheel on its full face, the axle on its 45° base cone inside the wheel's lower counterbore.\n- Support while printing: the wheel's lower counterbore narrows upward at 45° over the axle's base cone; the axle's head widens upward at 45° inside the wheel's upper counterbore; nothing in either body overhangs more than 45°.\n- Captured by the two cones: the axle's base cone (Ø12) cannot pass up through the Ø8.8 bore and its head (Ø13) cannot pass down through it, so the wheel cannot leave the axle.\n- Freeing it: hold the axle stem and turn the wheel a full turn each way; push the axle up and down once to break the first layer apart.\n- Motion: continuous rotation about the axle; free end play 0.57 mm each way and 0.40 mm radial, both from the geometry. No stops.\n- Mount: an M3 screw through the axle's Ø3.4 hole, or press the stem into a Ø13 socket.\n\nkey  value  what\ngap_mm  0.4  running gap per side on every moving interface (radial, axial, under captured parts) — part of the design, not a tolerance\nwheel_d_mm  40.0  wheel diameter\nwheel_w_mm  12.0  wheel thickness\npin_d_mm  8.0  axle journal diameter\nbore_d_mm  8.8  wheel bore (journal + 2 × 0.40)\nhead_d_mm  13.0  axle head diameter (45° cone from the journal)\nbase_d_mm  12.0  axle base-cone diameter on the bed\naxial_play_mm  0.57  free end play each way from the drawn position (0.40 square to the 45° cones)\nradial_play_mm  0.4  free radial play\nrotation_deg  360 continuous  wheel about the axle\nstem_h_mm  8.0  axle stem above the wheel\nscrew_hole_d_mm  3.4  through hole along the axle (M3)\n\nFiles elsewhere (not hosted by Xem Studio; license as stated by the publisher):\n- Xem Studio: Print-in-place mechanism design (geometry computed in the generator) — web — Xem Studio design — https://xemstudio.com/\n\nFree files (Xem Studio Design License, Xem Studio; STEP + STL, 3 parts): https://xemstudio.com/files/hardware/print-in-place-captive-wheel-axle/index.json\nAPI: https://xemstudio.com/api/geometry?object=print-in-place-captive-wheel-axle\n",
 "sources": [
  {
   "publisher": "Xem Studio",
   "title": "Print-in-place mechanism design (geometry computed in the generator)",
   "url": "https://xemstudio.com/",
   "formats": [
    "web"
   ],
   "license": "Xem Studio design",
   "license_verified": true,
   "hosted": false
  }
 ],
 "xem": {
  "status": "free-files",
  "sheet_free": true,
  "mesh_price_usd": null,
  "step_price_usd": null,
  "tolerance_mm": null
 },
 "related": [
  "print-in-place-barrel-hinge-180",
  "print-in-place-multi-knuckle-hinge",
  "print-in-place-captive-turntable",
  "print-in-place-dovetail-slider",
  "print-in-place-articulated-chain",
  "print-in-place-ball-joint",
  "print-in-place-push-button-flexure"
 ],
 "fits": [],
 "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": [],
 "faq": [
  {
   "q": "How is the wheel held on the axle?",
   "a": "By two 45° cones on the axle — a base cone Ø12 below the wheel's Ø8.8 bore and a head Ø13 above it — each 0.40 mm (square to the cone) from a matching counterbore in the wheel."
  },
  {
   "q": "How much end play does it have?",
   "a": "0.57 mm each way: the 0.40 mm gap measured square to a 45° face is 0.40 / sin 45° along the axle."
  }
 ],
 "files_license": {
  "name": "Xem Studio Design License",
  "holder": "Xem Studio",
  "url": "https://xemstudio.com/license/",
  "note": "Xem Studio's own design: free to use, print, modify and sell things made from it; not to be republished or redistributed as files."
 },
 "offers": [
  {
   "file": "print-in-place-captive-wheel-axle-assembly",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "Xem Studio Design License",
   "step": "https://xemstudio.com/files/hardware/print-in-place-captive-wheel-axle/print-in-place-captive-wheel-axle-assembly.step",
   "stl": "https://xemstudio.com/files/hardware/print-in-place-captive-wheel-axle/print-in-place-captive-wheel-axle-assembly.stl",
   "note": "The whole print as laid on the bed (2 bodies, already assembled); STEP keeps each moving body a separate solid"
  },
  {
   "file": "print-in-place-captive-wheel-axle-wheel",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "Xem Studio Design License",
   "step": "https://xemstudio.com/files/hardware/print-in-place-captive-wheel-axle/print-in-place-captive-wheel-axle-wheel.step",
   "stl": "https://xemstudio.com/files/hardware/print-in-place-captive-wheel-axle/print-in-place-captive-wheel-axle-wheel.stl",
   "note": "Wheel Ø40 × 12 with a 45° V tyre groove and six Ø7 windows; bore Ø8.8 with 45° counterbores top and bottom"
  },
  {
   "file": "print-in-place-captive-wheel-axle-axle",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "Xem Studio Design License",
   "step": "https://xemstudio.com/files/hardware/print-in-place-captive-wheel-axle/print-in-place-captive-wheel-axle-axle.step",
   "stl": "https://xemstudio.com/files/hardware/print-in-place-captive-wheel-axle/print-in-place-captive-wheel-axle-axle.stl",
   "note": "Printed axle: Ø8 journal, 45° base cone Ø12 on the bed, 45° head Ø13, stem to z 20, Ø3.4 through hole"
  }
 ],
 "markdown": "https://xemstudio.com/objects/print-in-place-captive-wheel-axle/index.md"
}