{
 "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": "compression-springs",
 "name": "Compression springs, wire Ø0.5–1.6, OD 6–16",
 "kind": "hardware",
 "category": "Hardware",
 "group": "Motion",
 "year": null,
 "question": "How do I calculate the rate of a compression spring?",
 "tags": [
  "compression spring",
  "spring",
  "rate",
  "coil spring",
  "stirling",
  "long earth society"
 ],
 "aliases": [
  "compression spring rate formula",
  "compression spring dimensions",
  "spring index",
  "compression spring step file",
  "spring solid height"
 ],
 "overall_mm": {
  "length": null,
  "width": null,
  "height": null
 },
 "official_cad": false,
 "xem_status": "free-files",
 "les": true,
 "free_files": 5,
 "url": "https://xemstudio.com/objects/compression-springs/",
 "sheet_txt": "https://xemstudio.com/objects/compression-springs/sheet.txt",
 "sheet": {
  "basis": "Helical compression spring with closed ends; rate k = G d⁴ / (8 D³ n), D = OD − d",
  "overall_mm": {
   "length": null,
   "width": null,
   "height": null
  },
  "notes": [
   "Envelopes at exact wire Ø, OD, ID (OD − 2 × wire) and free length, with closed (flat-ring) ends.",
   "Rate k = G d⁴ / (8 D³ n): G the shear modulus of the wire, d the wire Ø, D the mean coil Ø (OD − d), n the active coils. Halving the coils doubles the rate.",
   "Spring index D/d between 4 and 12 is makeable, 6–9 comfortable; these are 9 except the 0.5 × 6 at 11.",
   "Solid height is about (n + 2) × d; usable deflection about 0.8 × (free length − solid height). A pocket for one is drawn at the OD and a guide rod at the ID (see Mating features)."
  ],
  "table": {
   "columns": [
    "file",
    "wire Ø",
    "OD",
    "ID",
    "free length",
    "coils",
    "index D/d"
   ],
   "rows": [
    [
     "compression-d0.5-od6-l20",
     0.5,
     6,
     5,
     20,
     8,
     11
    ],
    [
     "compression-d0.8-od8-l25",
     0.8,
     8,
     6.4,
     25,
     10,
     9
    ],
    [
     "compression-d1-od10-l30",
     1,
     10,
     8,
     30,
     10,
     9
    ],
    [
     "compression-d1.2-od12-l40",
     1.2,
     12,
     9.6,
     40,
     12,
     9
    ],
    [
     "compression-d1.6-od16-l50",
     1.6,
     16,
     12.8,
     50,
     10,
     9
    ]
   ]
  }
 },
 "sheet_text": "Compression springs, wire Ø0.5–1.6, OD 6–16 — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/compression-springs/  (CC BY 4.0)\nBasis: Helical compression spring with closed ends; rate k = G d⁴ / (8 D³ n), D = OD − d\nCatalog version: 2026-10-20\n\nSizes: see table below\n- Envelopes at exact wire Ø, OD, ID (OD − 2 × wire) and free length, with closed (flat-ring) ends.\n- Rate k = G d⁴ / (8 D³ n): G the shear modulus of the wire, d the wire Ø, D the mean coil Ø (OD − d), n the active coils. Halving the coils doubles the rate.\n- Spring index D/d between 4 and 12 is makeable, 6–9 comfortable; these are 9 except the 0.5 × 6 at 11.\n- Solid height is about (n + 2) × d; usable deflection about 0.8 × (free length − solid height). A pocket for one is drawn at the OD and a guide rod at the ID (see Mating features).\n\nfile  wire Ø  OD  ID  free length  coils  index D/d\ncompression-d0.5-od6-l20  0.5  6  5.0  20  8  11.0\ncompression-d0.8-od8-l25  0.8  8  6.4  25  10  9.0\ncompression-d1-od10-l30  1.0  10  8.0  30  10  9.0\ncompression-d1.2-od12-l40  1.2  12  9.6  40  12  9.0\ncompression-d1.6-od16-l50  1.6  16  12.8  50  10  9.0\n\nFiles elsewhere (not hosted by Xem Studio; license as stated by the publisher):\n- Wikipedia: Spring (device) — web — CC BY-SA 4.0 (text) — https://en.wikipedia.org/wiki/Spring_(device)\n- McMaster-Carr: Compression springs (free STEP per part, for your own design use; no redistribution) — STEP, PDF — McMaster-Carr site terms [verify license at link] — https://www.mcmaster.com/products/compression-springs/\n- Lee Spring: Spring design formulas — web — Lee Spring site [verify license at link] — https://www.leespring.com/learn-about-springs\n- Long Earth Society: Engine and rig builds — web, video — LES site — https://longearthsociety.com/engineering/\n\nFree files (CC BY 4.0, Xem Studio; STEP + STL, 5 parts): https://xemstudio.com/files/hardware/compression-springs/index.json\nAPI: https://xemstudio.com/api/geometry?object=compression-springs\n",
 "sources": [
  {
   "publisher": "Wikipedia",
   "title": "Spring (device)",
   "url": "https://en.wikipedia.org/wiki/Spring_(device)",
   "formats": [
    "web"
   ],
   "license": "CC BY-SA 4.0 (text)",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "McMaster-Carr",
   "title": "Compression springs (free STEP per part, for your own design use; no redistribution)",
   "url": "https://www.mcmaster.com/products/compression-springs/",
   "formats": [
    "STEP",
    "PDF"
   ],
   "license": "McMaster-Carr site terms",
   "license_verified": false,
   "hosted": false
  },
  {
   "publisher": "Lee Spring",
   "title": "Spring design formulas",
   "url": "https://www.leespring.com/learn-about-springs",
   "formats": [
    "web"
   ],
   "license": "Lee Spring site",
   "license_verified": false,
   "hosted": false
  },
  {
   "publisher": "Long Earth Society",
   "title": "Engine and rig builds",
   "url": "https://longearthsociety.com/engineering/",
   "formats": [
    "web",
    "video"
   ],
   "license": "LES site",
   "license_verified": true,
   "hosted": false
  }
 ],
 "xem": {
  "status": "free-files",
  "sheet_free": true,
  "mesh_price_usd": null,
  "step_price_usd": null,
  "tolerance_mm": null
 },
 "related": [
  "extension-springs",
  "torsion-spring",
  "ratchet-pawl"
 ],
 "fits": [
  {
   "role": "Goes in or on",
   "items": [
    {
     "slug": "metric-shafts",
     "why": "guide rod at the spring ID"
    }
   ]
  },
  {
   "role": "Alternatives",
   "items": [
    {
     "slug": "extension-springs",
     "why": "pulls instead of pushes"
    }
   ]
  }
 ],
 "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": "spring OD",
   "exact": "OD (6–16)",
   "mates": "pocket of the same Ø",
   "fit": "socket",
   "files": "all"
  },
  {
   "feature": "spring ID",
   "exact": "OD − 2 × wire",
   "mates": "guide rod or arbor of the same Ø",
   "fit": "socket",
   "files": "all"
  }
 ],
 "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": "How do I calculate a compression spring rate?",
   "a": "k = G·d⁴ / (8·D³·n), with d wire Ø, D = OD − d, n active coils, G the wire's shear modulus."
  },
  {
   "q": "What is the solid height?",
   "a": "About (coils + 2) × wire Ø: the 10-coil, 1.0 wire, 30 long spring is about 12 mm solid."
  }
 ],
 "files_license": null,
 "offers": [
  {
   "file": "compression-d0.5-od6-l20",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/springs/compression-d0.5-od6-l20.step",
   "stl": "https://xemstudio.com/files/hardware/springs/compression-d0.5-od6-l20.stl",
   "note": "compression spring envelope: wire Ø0.5, OD 6, ID 5, 20 mm free length, closed ends, 8 coils"
  },
  {
   "file": "compression-d0.8-od8-l25",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/springs/compression-d0.8-od8-l25.step",
   "stl": "https://xemstudio.com/files/hardware/springs/compression-d0.8-od8-l25.stl",
   "note": "compression spring envelope: wire Ø0.8, OD 8, ID 6.4, 25 mm free length, closed ends, 10 coils"
  },
  {
   "file": "compression-d1-od10-l30",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/springs/compression-d1-od10-l30.step",
   "stl": "https://xemstudio.com/files/hardware/springs/compression-d1-od10-l30.stl",
   "note": "compression spring envelope: wire Ø1.0, OD 10, ID 8, 30 mm free length, closed ends, 10 coils"
  },
  {
   "file": "compression-d1.2-od12-l40",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/springs/compression-d1.2-od12-l40.step",
   "stl": "https://xemstudio.com/files/hardware/springs/compression-d1.2-od12-l40.stl",
   "note": "compression spring envelope: wire Ø1.2, OD 12, ID 9.6, 40 mm free length, closed ends, 12 coils"
  },
  {
   "file": "compression-d1.6-od16-l50",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "CC BY 4.0 (Xem Studio)",
   "step": "https://xemstudio.com/files/hardware/springs/compression-d1.6-od16-l50.step",
   "stl": "https://xemstudio.com/files/hardware/springs/compression-d1.6-od16-l50.stl",
   "note": "compression spring envelope: wire Ø1.6, OD 16, ID 12.8, 50 mm free length, closed ends, 10 coils"
  }
 ],
 "markdown": "https://xemstudio.com/objects/compression-springs/index.md"
}