{
 "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": "pololu-20d-metal-gearmotor-100-1-6v",
 "name": "Pololu 20D 100:1 metal gearmotor 6 V (#3454): body, Ø4 shaft and M2.5 face-plate holes",
 "kind": "modern",
 "category": "Electronic components",
 "group": "Motors",
 "year": null,
 "question": "What are the Pololu 20D 100:1 6 V gearmotor dimensions and face-plate mounting holes?",
 "tags": [
  "pololu 20d gearmotor",
  "20d metal gearmotor",
  "100:1 gearmotor",
  "6v gearmotor",
  "gearmotor mounting holes",
  "robot drive motor"
 ],
 "aliases": [
  "Pololu 3454",
  "Pololu #3454",
  "20Dx44L mm gearmotor",
  "pololu 20d metal gearmotor",
  "Pololu 100:1 Metal Gearmotor 20Dx44L mm 6V",
  "Pololu 20D dimensions",
  "20D gearmotor face plate holes"
 ],
 "overall_mm": {
  "length": 62.1,
  "width": 20,
  "height": 20
 },
 "official_cad": false,
 "xem_status": "free-files",
 "les": false,
 "free_files": 1,
 "url": "https://xemstudio.com/objects/pololu-20d-metal-gearmotor-100-1-6v/",
 "sheet_txt": "https://xemstudio.com/objects/pololu-20d-metal-gearmotor-100-1-6v/sheet.txt",
 "sheet": {
  "basis": "Pololu product page #3454 and the Pololu '20D mm Metal Gearmotors' dimension drawing; hole spacing cross-checked with the Pololu 20D bracket #1138 drawing.",
  "overall_mm": {
   "length": 62.1,
   "width": 20,
   "height": 20
  },
  "notes": [
   "Datum: motor axis along z, rear of the motor can at 0, output shaft toward +z.",
   "Motor can Ø20.0 × 25.1; gearbox Ø20.0 × 19.0 (L for 100:1), face plate at 44.1 from the rear.",
   "Output shaft Ø4.0 D-shaft extending 18.0 from the face plate (the D-flat is not dimensioned; drawn round).",
   "Two M2.5 threaded holes in the face plate, 15.0 apart on a line through the shaft (±7.5); maximum screw engagement 3.5 (modelled Ø2.5 × 3.5 deep).",
   "Gearbox length by ratio: 16.0 (25:1, 31:1), 17.5 (63:1, 78:1), 19.0 (100:1 to 195:1), 20.5 (250:1 to 488:1); 12 V, CB and extended-shaft versions share the face plate and shaft. Not modelled: rear motor terminals.",
   "Dimensions are exact nominal (true size), no tolerance added."
  ],
  "table": {
   "columns": [
    "feature",
    "x (mm)",
    "y (mm)",
    "size"
   ],
   "rows": [
    [
     "face-plate hole 1",
     "−7.5",
     "0",
     "M2.5, 3.5 max engagement"
    ],
    [
     "face-plate hole 2",
     "+7.5",
     "0",
     "M2.5, 3.5 max engagement"
    ],
    [
     "output shaft",
     "0",
     "0",
     "Ø4.0 D, 18.0 long"
    ]
   ]
  }
 },
 "sheet_text": "Pololu 20D 100:1 metal gearmotor 6 V (#3454): body, Ø4 shaft and M2.5 face-plate holes — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/pololu-20d-metal-gearmotor-100-1-6v/  (sheet CC BY 4.0)\nBasis: Pololu product page #3454 and the Pololu '20D mm Metal Gearmotors' dimension drawing; hole spacing cross-checked with the Pololu 20D bracket #1138 drawing.\nCatalog version: 2026-10-20\n\nOverall (mm): length 62.1, width 20.0, height 20.0\n- Datum: motor axis along z, rear of the motor can at 0, output shaft toward +z.\n- Motor can Ø20.0 × 25.1; gearbox Ø20.0 × 19.0 (L for 100:1), face plate at 44.1 from the rear.\n- Output shaft Ø4.0 D-shaft extending 18.0 from the face plate (the D-flat is not dimensioned; drawn round).\n- Two M2.5 threaded holes in the face plate, 15.0 apart on a line through the shaft (±7.5); maximum screw engagement 3.5 (modelled Ø2.5 × 3.5 deep).\n- Gearbox length by ratio: 16.0 (25:1, 31:1), 17.5 (63:1, 78:1), 19.0 (100:1 to 195:1), 20.5 (250:1 to 488:1); 12 V, CB and extended-shaft versions share the face plate and shaft. Not modelled: rear motor terminals.\n- Dimensions are exact nominal (true size), no tolerance added.\n\nfeature  x (mm)  y (mm)  size\nface-plate hole 1  −7.5  0  M2.5, 3.5 max engagement\nface-plate hole 2  +7.5  0  M2.5, 3.5 max engagement\noutput shaft  0  0  Ø4.0 D, 18.0 long\n\nFiles elsewhere (not hosted by Xem Studio; license as stated by the publisher):\n- Pololu: 100:1 Metal Gearmotor 20Dx44L mm 6V (#3454) — web — Publisher's page; dimensions are facts — https://www.pololu.com/product/3454\n- Pololu: 20D mm Metal Gearmotors dimension drawing — web — Publisher's page; dimensions are facts — https://www.pololu.com/file/0J1242/20d-metal-gearmotor-dimension-diagram.pdf\n- Pololu: 20D gearmotor bracket #1138 dimensions — web — Publisher's page; dimensions are facts — https://pololu.com/file/0J724/1138-bracket-dimensions.pdf\n\nFree files (CC BY 4.0, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/pololu-20d-metal-gearmotor-100-1-6v/index.json\nAPI: https://xemstudio.com/api/geometry?object=pololu-20d-metal-gearmotor-100-1-6v\n",
 "sources": [
  {
   "publisher": "Pololu",
   "title": "100:1 Metal Gearmotor 20Dx44L mm 6V (#3454)",
   "url": "https://www.pololu.com/product/3454",
   "formats": [
    "web"
   ],
   "license": "Publisher's page; dimensions are facts",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "Pololu",
   "title": "20D mm Metal Gearmotors dimension drawing",
   "url": "https://www.pololu.com/file/0J1242/20d-metal-gearmotor-dimension-diagram.pdf",
   "formats": [
    "web"
   ],
   "license": "Publisher's page; dimensions are facts",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "Pololu",
   "title": "20D gearmotor bracket #1138 dimensions",
   "url": "https://pololu.com/file/0J724/1138-bracket-dimensions.pdf",
   "formats": [
    "web"
   ],
   "license": "Publisher's page; dimensions are facts",
   "license_verified": true,
   "hosted": false
  }
 ],
 "xem": {
  "status": "free-files",
  "sheet_free": true,
  "mesh_price_usd": null,
  "step_price_usd": null,
  "tolerance_mm": null
 },
 "related": [
  "775-dc-motor",
  "jga25-370-gearmotor",
  "shaft-couplers",
  "metric-shafts",
  "machine-screws-metric-pan-cheese-csk"
 ],
 "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": [
  {
   "feature": "face-plate holes",
   "exact": "2 × M2.5, 15.0 apart, 3.5 max engagement",
   "mates": "Pololu 20D bracket or a custom bracket, M2.5 screws",
   "fit": "designed",
   "files": "all"
  },
  {
   "feature": "output shaft",
   "exact": "Ø4.0 D-shaft, 18.0 long",
   "mates": "wheel hub, coupler or adapter",
   "fit": "slide",
   "files": "all"
  },
  {
   "feature": "gearbox body",
   "exact": "Ø20.0",
   "mates": "clamp-style motor mount",
   "fit": "clamp",
   "files": "all"
  }
 ],
 "fit_classes": {
  "press": "stays put: pin, tube, bearing or magnet held by interference. ISO 286 equivalent: H7/p6 (locational interference) or tighter.",
  "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. ISO 286 equivalent: H7/g6 or H7/h6.",
  "run": "turns or slides in use: pin in a link, rod through a guide. ISO 286 equivalent: H8/f7 (close running).",
  "socket": "large sliding fit: syringe barrel, sleeve, bobbin in a bore. ISO 286 equivalent: H9/d9 (free running) or looser.",
  "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 are the Pololu 20D face-plate holes?",
   "a": "Two M2.5 threaded holes 15.0 mm apart on a line through the shaft; use at most 3.5 mm of screw engagement."
  },
  {
   "q": "How long is the 20D 100:1 gearmotor?",
   "a": "44.1 mm body (25.1 mm motor + 19.0 mm gearbox), Ø20 mm, plus an 18 mm Ø4 mm D-shaft: 62.1 mm overall."
  }
 ],
 "files_license": null,
 "offers": [
  {
   "file": "pololu-20d-metal-gearmotor-100-1-6v",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/pololu-20d-metal-gearmotor-100-1-6v/pololu-20d-metal-gearmotor-100-1-6v.step",
   "stl": "https://xemstudio.com/files/hardware/pololu-20d-metal-gearmotor-100-1-6v/pololu-20d-metal-gearmotor-100-1-6v.stl",
   "note": "Pololu 20D 100:1 metal gearmotor 6 V (#3454): body, Ø4 shaft and M2.5 face-plate holes"
  }
 ],
 "markdown": "https://xemstudio.com/objects/pololu-20d-metal-gearmotor-100-1-6v/index.md"
}