{
 "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": "t8-lead-screw",
 "name": "T8 lead screw Tr8×8 envelope, 100 to 400 mm",
 "kind": "hardware",
 "category": "Hardware",
 "group": "Motion",
 "year": null,
 "question": "What are the dimensions of a T8 lead screw?",
 "tags": [
  "lead screw",
  "t8",
  "tr8x8",
  "trapezoidal",
  "z axis"
 ],
 "aliases": [
  "t8 lead screw",
  "tr8x8 dimensions",
  "t8 lead screw step",
  "8mm lead screw",
  "trapezoidal screw 8mm"
 ],
 "overall_mm": {
  "length": null,
  "width": null,
  "height": null
 },
 "official_cad": false,
 "xem_status": "free-files",
 "les": false,
 "free_files": 6,
 "url": "https://xemstudio.com/objects/t8-lead-screw/",
 "sheet_txt": "https://xemstudio.com/objects/t8-lead-screw/sheet.txt",
 "sheet": {
  "basis": "Tr8×8(P2) trapezoidal lead screw, 4-start: Ø8 major, 2 mm pitch, 8 mm lead; envelope only",
  "overall_mm": {
   "length": null,
   "width": null,
   "height": null
  },
  "notes": [
   "Ø8 envelope, 100, 150, 200, 250, 300 and 400 long; the thread is not drawn.",
   "Tr8×8(P2): 2 mm pitch, four starts, 8 mm of travel per turn. Tr8×2 (single start, 2 mm per turn) has the same envelope; four thread ends visible on the screw's end face mean 8 mm lead.",
   "The end goes into a 5 → 8 mm coupler on a NEMA 17 or a bearing of 8 mm bore."
  ],
  "table": {
   "columns": [
    "file",
    "Ø",
    "length"
   ],
   "rows": [
    [
     "t8-screw-100",
     8,
     100
    ],
    [
     "t8-screw-150",
     8,
     150
    ],
    [
     "t8-screw-200",
     8,
     200
    ],
    [
     "t8-screw-250",
     8,
     250
    ],
    [
     "t8-screw-300",
     8,
     300
    ],
    [
     "t8-screw-400",
     8,
     400
    ]
   ]
  }
 },
 "sheet_text": "T8 lead screw Tr8×8 envelope, 100 to 400 mm — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/t8-lead-screw/  (CC BY 4.0)\nBasis: Tr8×8(P2) trapezoidal lead screw, 4-start: Ø8 major, 2 mm pitch, 8 mm lead; envelope only\nCatalog version: 2026-10-20\n\nSizes: see table below\n- Ø8 envelope, 100, 150, 200, 250, 300 and 400 long; the thread is not drawn.\n- Tr8×8(P2): 2 mm pitch, four starts, 8 mm of travel per turn. Tr8×2 (single start, 2 mm per turn) has the same envelope; four thread ends visible on the screw's end face mean 8 mm lead.\n- The end goes into a 5 → 8 mm coupler on a NEMA 17 or a bearing of 8 mm bore.\n\nfile  Ø  length\nt8-screw-100  8  100\nt8-screw-150  8  150\nt8-screw-200  8  200\nt8-screw-250  8  250\nt8-screw-300  8  300\nt8-screw-400  8  400\n\nFiles elsewhere (not hosted by Xem Studio; license as stated by the publisher):\n- Wikipedia: Leadscrew — web — CC BY-SA 4.0 (text) — https://en.wikipedia.org/wiki/Leadscrew\n- McMaster-Carr: Lead screws and nuts (free STEP/IGES/STL per part, for your own design use; no redistribution) — STEP, IGES, STL, PDF — McMaster-Carr site terms: personal design use, no redistribution [verify license at link] — https://www.mcmaster.com/products/lead-screws/\n\nFree files (CC BY 4.0, Xem Studio; STEP + STL, 6 parts): https://xemstudio.com/files/hardware/t8-lead-screw/index.json\nAPI: https://xemstudio.com/api/geometry?object=t8-lead-screw\n",
 "sources": [
  {
   "publisher": "Wikipedia",
   "title": "Leadscrew",
   "url": "https://en.wikipedia.org/wiki/Leadscrew",
   "formats": [
    "web"
   ],
   "license": "CC BY-SA 4.0 (text)",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "McMaster-Carr",
   "title": "Lead screws and nuts (free STEP/IGES/STL per part, for your own design use; no redistribution)",
   "url": "https://www.mcmaster.com/products/lead-screws/",
   "formats": [
    "STEP",
    "IGES",
    "STL",
    "PDF"
   ],
   "license": "McMaster-Carr site terms: personal design use, no redistribution",
   "license_verified": false,
   "hosted": false
  }
 ],
 "xem": {
  "status": "free-files",
  "sheet_free": true,
  "mesh_price_usd": null,
  "step_price_usd": null,
  "tolerance_mm": null
 },
 "related": [
  "t8-nut",
  "nema-17-stepper",
  "shaft-couplers",
  "608-bearing"
 ],
 "fits": [
  {
   "role": "Goes in or on",
   "items": [
    {
     "slug": "608-bearing",
     "why": "Ø8 end in a 608"
    }
   ]
  },
  {
   "role": "Connects to",
   "items": [
    {
     "slug": "t8-nut",
     "why": "Tr8×8 thread through the nut"
    },
    {
     "slug": "shaft-couplers",
     "why": "5 → 8 coupler to the motor"
    },
    {
     "slug": "nema-17-stepper",
     "why": "drives the screw"
    }
   ]
  }
 ],
 "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": "screw",
   "exact": "Ø8",
   "mates": "coupler bore or bearing",
   "fit": "slide",
   "files": "t8-screw-"
  }
 ],
 "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": "Is T8 lead 2 mm or 8 mm?",
   "a": "Both are sold as T8. Tr8×8 (4-start) moves 8 mm per turn; Tr8×2 moves 2 mm. Four thread ends on the screw end = 8 mm lead."
  },
  {
   "q": "What is the T8 pitch?",
   "a": "2 mm between threads; with 4 starts the lead is 8 mm."
  }
 ],
 "files_license": null,
 "offers": [
  {
   "file": "t8-screw-100",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/lead-screw-t8/t8-screw-100.step",
   "stl": "https://xemstudio.com/files/hardware/lead-screw-t8/t8-screw-100.stl",
   "note": "T8 lead screw envelope Ø8 × 100 (thread not modeled)"
  },
  {
   "file": "t8-screw-150",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/lead-screw-t8/t8-screw-150.step",
   "stl": "https://xemstudio.com/files/hardware/lead-screw-t8/t8-screw-150.stl",
   "note": "T8 lead screw envelope Ø8 × 150 (thread not modeled)"
  },
  {
   "file": "t8-screw-200",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/lead-screw-t8/t8-screw-200.step",
   "stl": "https://xemstudio.com/files/hardware/lead-screw-t8/t8-screw-200.stl",
   "note": "T8 lead screw envelope Ø8 × 200 (thread not modeled)"
  },
  {
   "file": "t8-screw-250",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/lead-screw-t8/t8-screw-250.step",
   "stl": "https://xemstudio.com/files/hardware/lead-screw-t8/t8-screw-250.stl",
   "note": "T8 lead screw envelope Ø8 × 250 (thread not modeled)"
  },
  {
   "file": "t8-screw-300",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/lead-screw-t8/t8-screw-300.step",
   "stl": "https://xemstudio.com/files/hardware/lead-screw-t8/t8-screw-300.stl",
   "note": "T8 lead screw envelope Ø8 × 300 (thread not modeled)"
  },
  {
   "file": "t8-screw-400",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/lead-screw-t8/t8-screw-400.step",
   "stl": "https://xemstudio.com/files/hardware/lead-screw-t8/t8-screw-400.stl",
   "note": "T8 lead screw envelope Ø8 × 400 (thread not modeled)"
  }
 ],
 "markdown": "https://xemstudio.com/objects/t8-lead-screw/index.md"
}