{
 "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": "screw-jack-screw-tr16x4",
 "name": "Screw-jack screw Tr16×4, 90 mm thread, Ø28 head with tommy-bar holes",
 "kind": "modern",
 "category": "Hardware",
 "group": "Mechanism parts",
 "year": null,
 "question": "What thread does a screw jack use?",
 "tags": [
  "mechanism part",
  "507 mechanical movements"
 ],
 "aliases": [
  "jack screw",
  "lifting screw",
  "trapezoidal screw tr16",
  "husillo de gato",
  "Hubspindel"
 ],
 "overall_mm": {
  "length": 28,
  "width": 28,
  "height": 106
 },
 "official_cad": false,
 "xem_status": "free-files",
 "les": false,
 "free_files": 1,
 "url": "https://xemstudio.com/objects/screw-jack-screw-tr16x4/",
 "sheet_txt": "https://xemstudio.com/objects/screw-jack-screw-tr16x4/sheet.txt",
 "sheet": {
  "basis": "Xem Studio design following Brown's figure (1868); true size, no printing allowance",
  "overall_mm": {
   "length": 28,
   "width": 28,
   "height": 106
  },
  "notes": [
   "Tr16×4 trapezoidal (ISO 2904 basic profile, 30°) screw, 90 mm of thread, with a Ø28 × 16 head cross-drilled Ø6 both ways for a tommy bar.",
   "Lift per turn = pitch = 4 mm; with friction coefficient 0.15 a 30° Tr thread at this lead angle (4.5°) is self-locking, so the load stays up.",
   "Xem Studio design following Brown's figure; true size, no printing allowance (apply your own to the mating features)."
  ],
  "table": {
   "columns": [
    "dimension",
    "value"
   ],
   "rows": [
    [
     "thread",
     "Tr16×4, single start, right hand"
    ],
    [
     "thread length",
     "90 mm"
    ],
    [
     "minor Ø (basic)",
     "12 mm"
    ],
    [
     "head",
     "Ø28 × 16, 2 × Ø6 cross holes"
    ]
   ]
  }
 },
 "sheet_text": "Screw-jack screw Tr16×4, 90 mm thread, Ø28 head with tommy-bar holes — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/screw-jack-screw-tr16x4/  (CC BY 4.0)\nBasis: Xem Studio design following Brown's figure (1868); true size, no printing allowance\nCatalog version: 2026-10-20\n\nOverall (mm): length 28.0, width 28.0, height 106.0\n- Tr16×4 trapezoidal (ISO 2904 basic profile, 30°) screw, 90 mm of thread, with a Ø28 × 16 head cross-drilled Ø6 both ways for a tommy bar.\n- Lift per turn = pitch = 4 mm; with friction coefficient 0.15 a 30° Tr thread at this lead angle (4.5°) is self-locking, so the load stays up.\n- Xem Studio design following Brown's figure; true size, no printing allowance (apply your own to the mating features).\n\ndimension  value\nthread  Tr16×4, single start, right hand\nthread length  90 mm\nminor Ø (basic)  12 mm\nhead  Ø28 × 16, 2 × Ø6 cross holes\n\nFiles elsewhere (not hosted by Xem Studio; license as stated by the publisher):\n- Henry T. Brown (1868, public domain): Five Hundred and Seven Mechanical Movements — scan on archive.org — web — Publisher's page; dimensions are facts — https://archive.org/details/fivehundredseven00browiala\n- 507movements.com: Brown's movement No. 389: figure, his text and an animation — web — Publisher's page; dimensions are facts — https://507movements.com/mm_389.html\n- Xem Studio: drawing — web — Publisher's page; dimensions are facts — https://xemstudio.com/objects/screw-jack-mechanism/\n\nFree files (CC BY 4.0, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/screw-jack-screw-tr16x4/index.json\nAPI: https://xemstudio.com/api/geometry?object=screw-jack-screw-tr16x4\n",
 "sources": [
  {
   "publisher": "Henry T. Brown (1868, public domain)",
   "title": "Five Hundred and Seven Mechanical Movements — scan on archive.org",
   "url": "https://archive.org/details/fivehundredseven00browiala",
   "formats": [
    "web"
   ],
   "license": "Publisher's page; dimensions are facts",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "507movements.com",
   "title": "Brown's movement No. 389: figure, his text and an animation",
   "url": "https://507movements.com/mm_389.html",
   "formats": [
    "web"
   ],
   "license": "Publisher's page; dimensions are facts",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "Xem Studio",
   "title": "drawing",
   "url": "https://xemstudio.com/objects/screw-jack-mechanism/",
   "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": [
  "screw-jack-mechanism"
 ],
 "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": "What thread does a screw jack use?",
   "a": "Tr16×4 trapezoidal (ISO 2904 basic profile, 30°) screw, 90 mm of thread, with a Ø28 × 16 head cross-drilled Ø6 both ways for a tommy bar."
  }
 ],
 "files_license": null,
 "offers": [
  {
   "file": "screw-jack-screw-tr16x4",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/screw-jack-screw-tr16x4/screw-jack-screw-tr16x4.step",
   "stl": "https://xemstudio.com/files/hardware/screw-jack-screw-tr16x4/screw-jack-screw-tr16x4.stl",
   "note": "screw, axis Z, thread z 0..90, head z 90..106"
  }
 ],
 "markdown": "https://xemstudio.com/objects/screw-jack-screw-tr16x4/index.md"
}