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Spur gears, module 2.5: 10 to 80 teeth (20° involute)

What is the pitch diameter of a module 2.5 spur gear? · Hardware · basis: ISO 53 basic rack: 20° pressure angle, addendum m, dedendum 1.25 m; pitch Ø = m × teeth, tip Ø = m × (teeth + 2), root Ø = m × (teeth − 2.5)

Exact dimensions. True size, with no printing tolerance added.

sizes
26 in table

Notes

  • Centre distance of two module 2.5 gears = m × (N1 + N2) / 2. Face width 20 mm, plain bore (add a hub, key or set screw to suit). Teeth below 17 are drawn without profile shift, so they undercut as real unshifted gears do.

Sizes

teethpitch_dia_mmtip_dia_mmroot_dia_mmface_mmbore_mm
1025.030.018.7520.07
1230.035.023.7520.08
1435.040.028.7520.010
1537.542.531.2520.011
1640.045.033.7520.012
1845.050.038.7520.014
2050.055.043.7520.015
2255.060.048.7520.017
2460.065.053.7520.019
2562.567.556.2520.020
2870.075.063.7520.022
3075.080.068.7520.024
3280.085.073.7520.025
3587.592.581.2520.025
3690.095.083.7520.025
40100.0105.093.7520.025
42105.0110.098.7520.025
45112.5117.5106.2520.025
48120.0125.0113.7520.025
50125.0130.0118.7520.025
56140.0145.0133.7520.025
60150.0155.0143.7520.025
64160.0165.0153.7520.025
70175.0180.0168.7520.025
72180.0185.0173.7520.025
80200.0205.0193.7520.025

Where the files are

Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.

ISOISO 53 standard basic rack (20° pressure angle, addendum 1 m, dedendum 1.25 m) and ISO 54 modulesstandardISO; dimensions are facts verify

Free files

★ Free files 26 parts. Generated by Xem Studio from the standard; threads are plain cylinders at major diameter. CC BY 4.0. index.json

gear-m2-5-10tmodule 2.5, 10 teeth: pitch Ø25, tip Ø30, root Ø18.75, face 20, bore Ø7STEP · STL
gear-m2-5-12tmodule 2.5, 12 teeth: pitch Ø30, tip Ø35, root Ø23.75, face 20, bore Ø8STEP · STL
gear-m2-5-14tmodule 2.5, 14 teeth: pitch Ø35, tip Ø40, root Ø28.75, face 20, bore Ø10STEP · STL
gear-m2-5-15tmodule 2.5, 15 teeth: pitch Ø37.5, tip Ø42.5, root Ø31.25, face 20, bore Ø11STEP · STL
gear-m2-5-16tmodule 2.5, 16 teeth: pitch Ø40, tip Ø45, root Ø33.75, face 20, bore Ø12STEP · STL
gear-m2-5-18tmodule 2.5, 18 teeth: pitch Ø45, tip Ø50, root Ø38.75, face 20, bore Ø14STEP · STL
gear-m2-5-20tmodule 2.5, 20 teeth: pitch Ø50, tip Ø55, root Ø43.75, face 20, bore Ø15STEP · STL
gear-m2-5-22tmodule 2.5, 22 teeth: pitch Ø55, tip Ø60, root Ø48.75, face 20, bore Ø17STEP · STL
gear-m2-5-24tmodule 2.5, 24 teeth: pitch Ø60, tip Ø65, root Ø53.75, face 20, bore Ø19STEP · STL
gear-m2-5-25tmodule 2.5, 25 teeth: pitch Ø62.5, tip Ø67.5, root Ø56.25, face 20, bore Ø20STEP · STL
gear-m2-5-28tmodule 2.5, 28 teeth: pitch Ø70, tip Ø75, root Ø63.75, face 20, bore Ø22STEP · STL
gear-m2-5-30tmodule 2.5, 30 teeth: pitch Ø75, tip Ø80, root Ø68.75, face 20, bore Ø24STEP · STL
gear-m2-5-32tmodule 2.5, 32 teeth: pitch Ø80, tip Ø85, root Ø73.75, face 20, bore Ø25STEP · STL
gear-m2-5-35tmodule 2.5, 35 teeth: pitch Ø87.5, tip Ø92.5, root Ø81.25, face 20, bore Ø25STEP · STL
gear-m2-5-36tmodule 2.5, 36 teeth: pitch Ø90, tip Ø95, root Ø83.75, face 20, bore Ø25STEP · STL
gear-m2-5-40tmodule 2.5, 40 teeth: pitch Ø100, tip Ø105, root Ø93.75, face 20, bore Ø25STEP · STL
gear-m2-5-42tmodule 2.5, 42 teeth: pitch Ø105, tip Ø110, root Ø98.75, face 20, bore Ø25STEP · STL
gear-m2-5-45tmodule 2.5, 45 teeth: pitch Ø112.5, tip Ø117.5, root Ø106.25, face 20, bore Ø25STEP · STL
gear-m2-5-48tmodule 2.5, 48 teeth: pitch Ø120, tip Ø125, root Ø113.75, face 20, bore Ø25STEP · STL
gear-m2-5-50tmodule 2.5, 50 teeth: pitch Ø125, tip Ø130, root Ø118.75, face 20, bore Ø25STEP · STL
gear-m2-5-56tmodule 2.5, 56 teeth: pitch Ø140, tip Ø145, root Ø133.75, face 20, bore Ø25STEP · STL
gear-m2-5-60tmodule 2.5, 60 teeth: pitch Ø150, tip Ø155, root Ø143.75, face 20, bore Ø25STEP · STL
gear-m2-5-64tmodule 2.5, 64 teeth: pitch Ø160, tip Ø165, root Ø153.75, face 20, bore Ø25STEP · STL
gear-m2-5-70tmodule 2.5, 70 teeth: pitch Ø175, tip Ø180, root Ø168.75, face 20, bore Ø25STEP · STL
gear-m2-5-72tmodule 2.5, 72 teeth: pitch Ø180, tip Ø185, root Ø173.75, face 20, bore Ø25STEP · STL
gear-m2-5-80tmodule 2.5, 80 teeth: pitch Ø200, tip Ø205, root Ø193.75, face 20, bore Ø25STEP · STL
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Plain text: sheet.txt · JSON: /api/geometry?object=spur-gears-module-2-5

Spur gears, module 2.5: 10 to 80 teeth (20° involute), isometric render of a generated part
Render of gear-m2-5-35t from the free STEP; not to scale.

Fits with

Spur gears, module 0.5: 10 to 80 teeth (20° involute), isometric render of a generated part
Spur gears, module 0.5: 10 to 80 teeth (20° involute)26 sizes★ 26 files
Spur gears, module 0.8: 10 to 80 teeth (20° involute), isometric render of a generated part
Spur gears, module 0.8: 10 to 80 teeth (20° involute)26 sizes★ 26 files
Spur gears, module 1: 10 to 80 teeth (20° involute), isometric render of a generated part
Spur gears, module 1: 10 to 80 teeth (20° involute)26 sizes★ 26 files
Spur gears, module 1.25: 10 to 80 teeth (20° involute), isometric render of a generated part
Spur gears, module 1.25: 10 to 80 teeth (20° involute)26 sizes★ 26 files
Spur gears, module 1.5: 10 to 80 teeth (20° involute), isometric render of a generated part
Spur gears, module 1.5: 10 to 80 teeth (20° involute)26 sizes★ 26 files
Spur gears, involute 20°: module 0.5, 1 and 2, 12–60 teeth, isometric render of a generated part
Spur gears, involute 20°: module 0.5, 1 and 2, 12–60 teeth21 sizes★ 21 files

Questions

Pitch diameter of a module 2.5, 20-tooth gear?

50 mm; tip 55 mm.

Centre distance?

m × (N1 + N2) / 2: a 20 and a 40 tooth module 2.5 pair sit 75 mm apart.