{
 "digest": null,
 "links": {
  "fits": [],
  "members": [],
  "cases": [],
  "assemblies": []
 },
 "prints": [],
 "part": {
  "id": "28byj48-stepper",
  "name": "28BYJ-48 5V Geared Stepper (+ ULN2003 driver board)",
  "kind": "",
  "method": "",
  "vendor": "generic",
  "sku": "",
  "model": "",
  "buy": [
   "https://www.amazon.com/s?k=28byj-48+uln2003"
  ],
  "url": "",
  "category": "motor",
  "owned_qty": 0
 },
 "facts": {
  "id": "28byj48-stepper",
  "name": "28BYJ-48 5V Geared Stepper (+ ULN2003 driver board)",
  "vendor": "amazon",
  "url": null,
  "qty_owned": 5,
  "category": "motor",
  "hw_tags": [
   "28byj-48",
   "uln2003"
  ],
  "frame": "origin plan bottom-left of flange bbox (42 x 28), Z=0 body rear, shaft +Z at (21, 22) = body center +8 in Y",
  "pic": "PXL_20260723_143630906.jpg",
  "body": {
   "size_mm": [
    42.0,
    28.0,
    30.0
   ],
   "outline": "irregular",
   "notes": "radial wire exit (5-wire JST-XH lead) on the -Y side near the base - NOT modeled, leave ~15 clearance"
  },
  "mounting": {
   "holes": [
    {
     "xy": [
      3.5,
      14.0
     ],
     "dia": 4.2,
     "thread": null,
     "notes": "ear tab"
    },
    {
     "xy": [
      38.5,
      14.0
     ],
     "dia": 4.2,
     "thread": null
    }
   ],
   "pattern": "35.0 hole-to-hole (fits M4 or M3+washer)",
   "shaft": {
    "dia": 5.0,
    "len": 10.0,
    "flat": "double-D flats ~3 across - NOT modeled",
    "notes": "axis (21, 22); collar boss dia 9 x 1.5 under shaft"
   },
   "notes": "flange is on the SHAFT face - motor hangs from the panel it bolts to"
  },
  "electrical": {
   "vin": "5V",
   "protocols": [
    "gpio-4phase"
   ],
   "notes": "unipolar 5-wire; 1:64 gearbox, 5.625/64 deg step; pairs with ULN2003 board (approx 35 x 32 PCB, 4x dia 3 holes - not measured, model if needed)"
  },
  "cad": {
   "file": "amz-28byj48-stepper.step",
   "fidelity": "envelope",
   "source": "amz-28byj48-stepper.py",
   "verified": true
  },
  "sources": [
   {
    "facts": "body dia 28, shaft dia 5 x 10",
    "ref": "https://www.utmel.com/components/28byj-48-5v-stepper-motor-28byj-48-datasheet-pinout-wiring",
    "date": "2026-07-23"
   },
   {
    "facts": "holes 35/dia 4.2, body h 19, shaft offset 8, flange/boss",
    "ref": "Kiatronics-style 28BYJ-48 datasheet drawing (community standard, typ.)",
    "date": "2026-07-23"
   }
  ],
  "confidence": "hole spacing/offset/body height are typ. datasheet-family values - caliper-verify before fit-critical use; ULN2003 board not modeled"
 },
 "models": [
  {
   "handle": "sarg",
   "fidelity": "envelope",
   "verified": true,
   "visibility": "public",
   "url": "/m/sarg/28byj48-stepper",
   "files": [
    "amz-28byj48-stepper.py",
    "amz-28byj48-stepper.step",
    "part.yaml"
   ]
  }
 ],
 "related": {
  "notes": {
   "exact": [],
   "chip": [
    {
     "handle": "sarg",
     "id": "28byj48-stalls-from-standstill-above-15rpm-ramp-and-burst",
     "title": "28BYJ-48 stepper stalls when commanded ~24 RPM from a standstill on a Pico \u2014 ~15 RPM (2 ms full-step) is the reliable ceiling; use an acceleration ramp and burst-stepping to go higher",
     "status": "provisional",
     "visibility": "public",
     "url": "/n/sarg/28byj48-stalls-from-standstill-above-15rpm-ramp-and-burst"
    }
   ],
   "addr": []
  },
  "parts": {
   "variants": [],
   "interface": [],
   "mounting": [],
   "cooccur": [],
   "owners": [],
   "addr": []
  }
 }
}