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Acme threads 1/4-16 to 2-4 (ASME B1.5): 1/2-10, 5/8-8, 3/4-6, 1-5, 1-1/2-4, 2-4: major, pitch and minor diameter, pitch

What are the major, pitch and minor diameters and the pitch of 1/2-10, 5/8-8, 3/4-6, 1-5 and 2-4 Acme lead screw threads? · Standard part · basis: Bornemann Gewindetechnik ASME B1.5 nominal-dimension table with formula checks on every row and MachiningDoctor pages for 5/16-14 and 2-4; numbers only

Also called: 1/4-16 Acme dimensions, 5/16-14 Acme dimensions, 3/8-12 Acme dimensions, 1/2-10 Acme dimensions, 5/8-8 Acme dimensions, 3/4-6 Acme dimensions, 7/8-6 Acme dimensions, 1-5 Acme dimensions, 1-1/4-5 Acme dimensions, 1-1/2-4 Acme dimensions, 2-4 Acme dimensions, Acme thread chart, Acme thread pitch diameter, Acme thread minor diameter, ACME lead screw TPI, 1/2-10 acme pitch diameter, 3/4-6 acme minor d

Exact dimensions. True size, with no tolerance added.

sizes
15 in table

Notes

  • General-purpose Acme (ASME B1.5, 29 degree flank angle) is the inch lead-screw thread: 1/2-10 Acme is a 1/2 in screw with 10 threads per inch, so the pitch (and, single-start, the lead) is 0.100 in. The basic formulas are d2 = d - P/2 and d1 = d - P; the generator checks both, and P = 1/TPI, on every row.
  • Numbers: Bornemann Gewindetechnik's ASME B1.5 nominal-dimension table (inches as printed), with MachiningDoctor's 5/16-14 and 2-4 pages as the independent check (5/16-14: major 0.3125, pitch 0.2768, minor 0.2411, pitch 0.07143; 2-4: pitch diameter 1.875, minor 1.75, pitch 0.25). The mm columns are the printed inch values times 25.4 (rounded to 0.01 mm). Bornemann's table runs on to 5-2 Acme; only 1/4 to 2 in are shown here.
  • Numbers only, no files: lead, start count and length are the user's choices and the helical form is not a published envelope. The Class 2G / 3G / 4G tolerance bands (MachiningDoctor prints them, e.g. 2-4 external pitch diameter 1.8402 to 1.8637 in) are left out.
  • Left out: stub Acme, centralizing Acme, Class 2G / 3G / 4G limits, multi-start leads, sizes above 2 in, the metric Tr thread (separate page).

Acme threads 1/4-16 to 2-4 (ASME B1.5): 1/2-10, 5/8-8, 3/4-6, 1-5… size chart

threadTPImajor Ø d, inpitch P, inpitch Ø d2, inminor Ø d1, ind, mmP, mmd2, mmd1, mm
1/4-16 Acme160.25000.06250.21880.18756.351.595.564.76
5/16-14 Acme140.31250.07140.27680.24117.941.817.036.12
3/8-12 Acme120.37500.08330.33330.29179.532.128.477.41
7/16-12 Acme120.43750.08330.39580.354211.112.1210.059.00
1/2-10 Acme100.50000.10000.45000.400012.702.5411.4310.16
5/8-8 Acme80.62500.12500.56250.500015.883.1814.2912.70
3/4-6 Acme60.75000.16670.66670.583319.054.2316.9314.82
7/8-6 Acme60.87500.16670.79170.708322.234.2320.1117.99
1-5 Acme51.00000.20000.90000.800025.405.0822.8620.32
1-1/8-5 Acme51.12500.20001.02500.925028.585.0826.0423.50
1-1/4-5 Acme51.25000.20001.15001.050031.755.0829.2126.67
1-3/8-4 Acme41.37500.25001.25001.125034.936.3531.7528.58
1-1/2-4 Acme41.50000.25001.37501.250038.106.3534.9331.75
1-3/4-4 Acme41.75000.25001.62501.500044.456.3541.2838.10
2-4 Acme42.00000.25001.87501.750050.806.3547.6344.45

Where the files are

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

Bornemann GewindetechnikACME thread according to ANSI / ASME B1.5-1977, nominal dimensions: d, d2 = D2, P, d1, 1/4-16 to 5-2 (with 3D model links)webPublisher's page; dimensions are facts
MachiningDoctorAcme thread basic dimensions (ASME B1.5): 5/16-14 and 2-4 pages (TPI, pitch, major, pitch, minor diameter)webPublisher's page; dimensions are facts

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Plain text: sheet.txt · JSON: /api/geometry?object=acme-threads-asme-b1-5-1-4-to-2-in

Schematic, not to scale.

Fits with

length
Trapezoidal lead screw threads Tr10 to Tr40 (ISO 2904 / DIN 103): Tr10x2, Tr12x3, Tr16x4, Tr20x4, Tr24x5, Tr30x6, Tr40x7: pitch, d2, D4, d3, D144 sizes★ sheet
T8 lead screw Tr8×8 envelope, 100 to 400 mm, isometric render of a generated part
T8 lead screw Tr8×8 envelope, 100 to 400 mm6 sizes★ 6 files
Lead screw Tr10×2, 80 mm thread, Ø6 journals, Ø20 head with Ø6 cross hole, isometric render of a generated part
Lead screw Tr10×2, 80 mm thread, Ø6 journals, Ø20 head with Ø6 cross hole20.0×20.0×118.0 mm★ 1 file
Lead screw and nut-slide (rotation to straight travel), Tr10×2, isometric render of a generated part
Lead screw and nut-slide (rotation to straight travel), Tr10×24 sizes★ 1 file
Thrust ball bearings 51100 series (51100 to 51130): bore, outside diameter, height, housing washer bore + STEP/STL envelopes, isometric render of a generated part
Thrust ball bearings 51100 series (51100 to 51130): bore, outside diameter, height, housing washer bore + STEP/STL envelopes25 sizes★ 11 files

Questions

What are the dimensions of a 1/2-10 Acme thread?

Major diameter 0.5000 in (12.70 mm), 10 TPI (pitch 0.1000 in = 2.54 mm), pitch diameter 0.4500 in, minor diameter 0.4000 in (Bornemann, ASME B1.5).

What are the dimensions of a 3/4-6 Acme thread?

Major 0.7500 in, 6 TPI (pitch 0.1667 in), pitch diameter 0.6667 in, minor diameter 0.5833 in.

What are the dimensions of a 1-5 Acme thread?

Major 1.0000 in, 5 TPI (pitch 0.2000 in), pitch diameter 0.9000 in, minor 0.8000 in.

What are the dimensions of a 2-4 Acme thread?

Major 2.0000 in, 4 TPI (pitch 0.2500 in), pitch diameter 1.8750 in, minor 1.7500 in; MachiningDoctor gives the same.

How do I get the pitch diameter of an Acme thread?

d2 = d - P/2 and the minor diameter d1 = d - P, with P = 1/TPI.