{
 "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": "trip-hammer-mechanism",
 "name": "Trip hammer: wiper cam pressing the tail of a first-order helve",
 "kind": "hardware",
 "category": "Mechanisms",
 "group": "Cams",
 "year": null,
 "question": "How does a trip hammer work?",
 "tags": [
  "mechanism",
  "cams",
  "kinematics",
  "507 mechanical movements"
 ],
 "aliases": [
  "trip hammer",
  "tilt hammer",
  "helve hammer",
  "cam hammer",
  "martinete de cola",
  "Schwanzhammer"
 ],
 "overall_mm": {
  "length": null,
  "width": null,
  "height": null
 },
 "official_cad": false,
 "xem_status": "free-files",
 "les": false,
 "free_files": 1,
 "url": "https://xemstudio.com/objects/trip-hammer-mechanism/",
 "sheet_txt": "https://xemstudio.com/objects/trip-hammer-mechanism/sheet.txt",
 "sheet": {
  "basis": "Xem Studio design following Brown No. 353 (1868)",
  "overall_mm": {
   "length": null,
   "width": null,
   "height": null
  },
  "notes": [
   "A shaft carrying wiper cams turns above the tail of the hammer helve: each lobe presses the tail down, the head at the other end of the lever rises, and when the lobe slips off the tail the head falls on the anvil. Two lobes give two blows per turn.",
   "First-order lever (fulcrum between cam and head): tail 80 mm, head 120 mm, so the head rises 1.5 × the cam's lift. Drawn with the helve at rest on the anvil and a lobe tip just touching the tail (contact only), ready to press.",
   "Brown's No. 353 (tilt hammer with the helve as a first-order lever, modified from No. 72, where it is a third-order lever).",
   "Parts (each has its own page): wiper-cam-2-lobe-r12-r24-b8, trip-hammer-helve-200x12, hammer-head-24x24x40, anvil-block-30x30x20, pivot-post-16x20x30-fork, linear-shafts-h6, dowel-pins-metric.",
   "Brown's movement No. 353 (1868) shows it; this model is a Xem Studio design following his figure, every part at true size."
  ],
  "table": {
   "columns": [
    "parameter",
    "value"
   ],
   "rows": [
    [
     "helve",
     "200 mm, pivot at 80 from the tail"
    ],
    [
     "cam",
     "2 lobes, lift 12 mm"
    ],
    [
     "head lift",
     "18 mm per blow"
    ],
    [
     "blows per turn",
     "2"
    ]
   ]
  }
 },
 "sheet_text": "Trip hammer: wiper cam pressing the tail of a first-order helve — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/trip-hammer-mechanism/  (sheet CC BY 4.0; files Xem Studio Design License, https://xemstudio.com/license/)\nBasis: Xem Studio design following Brown No. 353 (1868)\nCatalog version: 2026-10-20\n\nSizes: see table below\n- A shaft carrying wiper cams turns above the tail of the hammer helve: each lobe presses the tail down, the head at the other end of the lever rises, and when the lobe slips off the tail the head falls on the anvil. Two lobes give two blows per turn.\n- First-order lever (fulcrum between cam and head): tail 80 mm, head 120 mm, so the head rises 1.5 × the cam's lift. Drawn with the helve at rest on the anvil and a lobe tip just touching the tail (contact only), ready to press.\n- Brown's No. 353 (tilt hammer with the helve as a first-order lever, modified from No. 72, where it is a third-order lever).\n- Parts (each has its own page): wiper-cam-2-lobe-r12-r24-b8, trip-hammer-helve-200x12, hammer-head-24x24x40, anvil-block-30x30x20, pivot-post-16x20x30-fork, linear-shafts-h6, dowel-pins-metric.\n- Brown's movement No. 353 (1868) shows it; this model is a Xem Studio design following his figure, every part at true size.\n\nparameter  value\nhelve  200 mm, pivot at 80 from the tail\ncam  2 lobes, lift 12 mm\nhead lift  18 mm per blow\nblows per turn  2\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. 353: figure, his text and an animation — web — Publisher's page; dimensions are facts — https://507movements.com/mm_353.html\n\nFree files (Xem Studio Design License, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/trip-hammer-mechanism/index.json\nAPI: https://xemstudio.com/api/geometry?object=trip-hammer-mechanism\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. 353: figure, his text and an animation",
   "url": "https://507movements.com/mm_353.html",
   "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": [
  "wiper-cam-2-lobe-r12-r24-b8",
  "trip-hammer-helve-200x12",
  "hammer-head-24x24x40",
  "anvil-block-30x30x20",
  "pivot-post-16x20x30-fork",
  "linear-shafts-h6",
  "dowel-pins-metric"
 ],
 "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": "How does a trip hammer work?",
   "a": "A shaft carrying wiper cams turns above the tail of the hammer helve: each lobe presses the tail down, the head at the other end of the lever rises, and when the lobe slips off the tail the head falls on the anvil. Two lobes give two blows per turn."
  }
 ],
 "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": "trip-hammer-mechanism-assembly",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "Xem Studio Design License",
   "step": "https://xemstudio.com/files/hardware/trip-hammer-mechanism/trip-hammer-mechanism-assembly.step",
   "stl": "https://xemstudio.com/files/hardware/trip-hammer-mechanism/trip-hammer-mechanism-assembly.stl",
   "note": "Assembled mechanism, all parts placed at one pose (STEP keeps each part separate)"
  }
 ],
 "markdown": "https://xemstudio.com/objects/trip-hammer-mechanism/index.md"
}