{
 "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-multi-knuckle-hinge",
 "name": "Print-in-place: seven-knuckle hinge on a captive through-pin (58.4 mm)",
 "kind": "hardware",
 "category": "3D printing",
 "group": "Print-in-place mechanisms",
 "year": null,
 "question": "How do you 3D print a piano-style hinge with the pin already in?",
 "tags": [
  "3d printable",
  "print in place",
  "no assembly",
  "no supports",
  "mechanism",
  "stl",
  "step",
  "hinge"
 ],
 "aliases": [
  "print in place piano hinge",
  "print in place hinge with pin",
  "multi knuckle hinge stl",
  "captive pin hinge"
 ],
 "overall_mm": {
  "length": 58.4,
  "width": 60,
  "height": 9
 },
 "official_cad": false,
 "xem_status": "free-files",
 "les": false,
 "free_files": 3,
 "url": "https://xemstudio.com/objects/print-in-place-multi-knuckle-hinge/",
 "sheet_txt": "https://xemstudio.com/objects/print-in-place-multi-knuckle-hinge/sheet.txt",
 "sheet": {
  "basis": "Xem Studio design: horizontal through-pin, teardrop bores; one designed running gap of 0.40 mm",
  "overall_mm": {
   "length": 58.4,
   "width": 60,
   "height": 9
  },
  "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: opened flat, both leaves on the bed, axis horizontal 4.5 mm up; every knuckle stands on its 45° foot.",
   "Support while printing: the Ø3.6 pin belongs to leaf A and runs straight through all seven knuckles; across each leaf-B knuckle it is a 8.8 mm bridge between two leaf-A knuckles. The leaf-B bores have a 45° peaked roof (teardrop), so no ceiling is flat.",
   "Captured: the pin passes through every leaf-B knuckle and leaf A's knuckles close both ends, so leaf B cannot come off the pin or slide along it.",
   "Freeing it: hold leaf A and swing leaf B through its range a few times; the bridge layers under the pin may need one firm first turn.",
   "Motion: leaf B folds 183.3° up from flat (past 180°, face to face) and 98.9° down; stops are leaf on leaf (computed)."
  ],
  "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"
    ],
    [
     "hinge_l_mm",
     58.4,
     "length along the axis"
    ],
    [
     "knuckles",
     "7 × 8 mm",
     "4 on leaf A (both ends), 3 on leaf B"
    ],
    [
     "knuckle_d_mm",
     9,
     ""
    ],
    [
     "pin_d_mm",
     3.6,
     "through-pin, part of leaf A, runs the whole length"
    ],
    [
     "bore_d_mm",
     4.4,
     "leaf B knuckle bore, with a 45° peaked roof"
    ],
    [
     "leaf_w_mm",
     30,
     "each leaf, from the axis"
    ],
    [
     "leaf_t_mm",
     3.6,
     ""
    ],
    [
     "axis_h_mm",
     4.5,
     ""
    ],
    [
     "bridge_mm",
     8.8,
     "pin span between leaf A knuckles (printed as a bridge)"
    ],
    [
     "fold_up_deg",
     183.3,
     "leaf B from flat to the stop"
    ],
    [
     "fold_down_deg",
     98.9,
     "the other way"
    ],
    [
     "mount_holes",
     "3 × Ø3.4 per leaf",
     ""
    ]
   ]
  }
 },
 "sheet_text": "Print-in-place: seven-knuckle hinge on a captive through-pin (58.4 mm) — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/print-in-place-multi-knuckle-hinge/  (sheet CC BY 4.0; files Xem Studio Design License, https://xemstudio.com/license/)\nBasis: Xem Studio design: horizontal through-pin, teardrop bores; one designed running gap of 0.40 mm\nCatalog version: 2026-10-20\n\nOverall (mm): length 58.4, width 60.0, height 9.0\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: opened flat, both leaves on the bed, axis horizontal 4.5 mm up; every knuckle stands on its 45° foot.\n- Support while printing: the Ø3.6 pin belongs to leaf A and runs straight through all seven knuckles; across each leaf-B knuckle it is a 8.8 mm bridge between two leaf-A knuckles. The leaf-B bores have a 45° peaked roof (teardrop), so no ceiling is flat.\n- Captured: the pin passes through every leaf-B knuckle and leaf A's knuckles close both ends, so leaf B cannot come off the pin or slide along it.\n- Freeing it: hold leaf A and swing leaf B through its range a few times; the bridge layers under the pin may need one firm first turn.\n- Motion: leaf B folds 183.3° up from flat (past 180°, face to face) and 98.9° down; stops are leaf on leaf (computed).\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\nhinge_l_mm  58.4  length along the axis\nknuckles  7 × 8 mm  4 on leaf A (both ends), 3 on leaf B\nknuckle_d_mm  9.0  \npin_d_mm  3.6  through-pin, part of leaf A, runs the whole length\nbore_d_mm  4.4  leaf B knuckle bore, with a 45° peaked roof\nleaf_w_mm  30.0  each leaf, from the axis\nleaf_t_mm  3.6  \naxis_h_mm  4.5  \nbridge_mm  8.8  pin span between leaf A knuckles (printed as a bridge)\nfold_up_deg  183.3  leaf B from flat to the stop\nfold_down_deg  98.9  the other way\nmount_holes  3 × Ø3.4 per leaf  \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-multi-knuckle-hinge/index.json\nAPI: https://xemstudio.com/api/geometry?object=print-in-place-multi-knuckle-hinge\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-captive-wheel-axle",
  "print-in-place-barrel-hinge-180",
  "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": "Is the pin a separate part?",
   "a": "No — it is part of leaf A and prints with it; leaf B's knuckles print around it with 0.40 mm all round (bore Ø4.4 on a Ø3.6 pin)."
  },
  {
   "q": "Why are the bores pointed at the top?",
   "a": "A round horizontal hole has a flat ceiling at the top; the 45° peak lets it print without support. The pin never reaches the peak."
  }
 ],
 "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-multi-knuckle-hinge-assembly",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "Xem Studio Design License",
   "step": "https://xemstudio.com/files/hardware/print-in-place-multi-knuckle-hinge/print-in-place-multi-knuckle-hinge-assembly.step",
   "stl": "https://xemstudio.com/files/hardware/print-in-place-multi-knuckle-hinge/print-in-place-multi-knuckle-hinge-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-multi-knuckle-hinge-leaf-a",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "Xem Studio Design License",
   "step": "https://xemstudio.com/files/hardware/print-in-place-multi-knuckle-hinge/print-in-place-multi-knuckle-hinge-leaf-a.step",
   "stl": "https://xemstudio.com/files/hardware/print-in-place-multi-knuckle-hinge/print-in-place-multi-knuckle-hinge-leaf-a.stl",
   "note": "Leaf A: four knuckles and the Ø3.6 through-pin"
  },
  {
   "file": "print-in-place-multi-knuckle-hinge-leaf-b",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "Xem Studio Design License",
   "step": "https://xemstudio.com/files/hardware/print-in-place-multi-knuckle-hinge/print-in-place-multi-knuckle-hinge-leaf-b.step",
   "stl": "https://xemstudio.com/files/hardware/print-in-place-multi-knuckle-hinge/print-in-place-multi-knuckle-hinge-leaf-b.stl",
   "note": "Leaf B: three knuckles with teardrop bores"
  }
 ],
 "markdown": "https://xemstudio.com/objects/print-in-place-multi-knuckle-hinge/index.md"
}