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Acorn (domed cap) nuts, DIN 1587 high type: M4–M24 dome diameter, overall height, across flats, thread depth

What are the dimensions of a DIN 1587 acorn nut, and how tall is an M8 domed cap nut? · Standard part · basis: fasten.it's DIN 1587 table (07/2014) cross-checked against Westfield Fasteners' DIN 1587 table (same dk, h, s, t, e on M4 to M24; m differs, see notes); numbers only

Also called: din 1587 acorn nut dimensions, m8 acorn nut height, m6 cap nut size, m10 dome nut dimensions, acorn nut m5 across flats, din 1587 m12, m4 acorn nut size, acorn nut dome diameter m8, cap nut thread depth m6

Exact dimensions. True size, with no tolerance added.

sizes
12 in table

Notes

  • Columns (mm): P pitch; dk max, read as the dome diameter; h overall height (nominal = max); m max, read as the thread / body height; s width across flats (nominal = max; values in brackets are the alternative wrench widths the page prints for M10, M12, M14 and M22); e across corners (min); t min / max; x or g2 as printed on the right (x max for M4 to M10, g2 max for M12 and larger). The letters are the ones the pages print; fasten.it does not define them. Westfield's table (da, dk, dw, e, x, g2, h, m, r, s, t, w) agrees with fasten.it on dk, h, s, t and e (grade A minimum) for every size M4 to M24. The two disagree on m: fasten.it's coarse-thread m max is 10 for M10 (11.7 M12), Westfield prints m min 8.00 / max 7.64 for M10 (10.00 / 9.64 for M12), which equal fasten.it's fine-thread m (8.0, 10.0); the coarse values shown are fasten.it's and m is uncertain.
  • fasten.it also has a fine-thread table (M8x1 to M24x2) with the same dk, h and s but smaller m (e.g. M10x1.25: m 8.0 against 10.0 coarse); it is not reproduced here. fasten.it's M22x1.5 row prints t min 25.58 against 28.58 for M22x2, and the M27 and M30 coarse rows print fewer values than the columns, so they are left out. Grade A and B minimum figures are in Westfield's table (e.g. M8 e min 14.38 for grade A, 14.20 max for grade B).
  • No file: the dome profile (the radius r is only an auxiliary dimension) and the thread depth do not define a full solid in the sources read. McMaster-Carr sells acorn and cap nuts with per-part STEP; its metric acorn and cap-nut categories are linked, not copied. Nylon-insert nuts (domed or hex): nylon-insert-lock-nuts-iso-7040-din-985.

Acorn (domed cap) nuts, DIN 1587 high type: M4–M24 dome diameter… size chart

threadP (mm)dk maxh (nom = max)m maxs (nom = max)e mint min / maxx or g2 max
M40.76.584.177.665.26 / 5.74x 1.4
M50.87.5105.488.797.21 / 7.79x 1.6
M619.51261011.057.71 / 8.29x 2
M81.2512.5158.51314.3810.7 / 11.4x 2.5
M101.515181016 (17)17.7712.7 / 13.4x 3
M121.75172211.718 (19)20.0315.7 / 16.4g 6.4
M14220251321 (22)23.3517.7 / 18.4g 7.3
M1622328162426.7520.6 / 21.4g 7.3
M182.5263218.72729.5624.6 / 25.4g 9.3
M202.5283419.73032.9525.6 / 26.4g 9.3
M222.5333922.732 (34)37.2928.6 / 29.4g 9.3
M243344223.53639.5530.5 / 31.5g 10.7

Where the files are

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

fasten.itDIN 1587 hexagon domed cap nuts, high type (07/2014): d, P, da, dk, dw, e, x, g2, h, m, r, s, t, w; coarse M4 to M30 and fine threadwebReference page; numbers only. The page does not define the column letters
Westfield FastenersDIN 1587 dome nuts M4 to M24: da, dk, dw, e, h, m, r, s, t, w (Table 1)webPublisher's page; dimensions are facts
McMaster-CarrMetric acorn nuts (free STEP/IGES per part, for your own design use; no redistribution)STEP, IGES, PDFMcMaster-Carr site terms: personal design use, no redistribution verify
McMaster-CarrMetric cap nuts (free STEP/IGES per part, for your own design use; no redistribution)STEP, IGES, PDFMcMaster-Carr site terms: personal design use, no redistribution verify

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Plain text: sheet.txt · JSON: /api/geometry?object=acorn-cap-nuts-din-1587

Schematic, not to scale.

Fits with

Hex nuts, M2–M8 (ISO 4032), isometric render of a generated part
Hex nuts, M2–M8 (ISO 4032)7 sizes★ 7 files
Hex nuts, M10 to M24 (ISO 4032 / DIN 934), isometric render of a generated part
Hex nuts, M10 to M24 (ISO 4032 / DIN 934)6 sizes★ 6 files
Nylon-insert lock nuts (nyloc), ISO 7040 and DIN 985, M3–M36: width across flats, height, bearing diameter + M10–M30 envelope files, isometric render of a generated part
Nylon-insert lock nuts (nyloc), ISO 7040 and DIN 985, M3–M36: width across flats, height, bearing diameter + M10–M30 envelope files30.0×26.0×22.8 mm★ 6 files
Hex flange nuts, DIN 6923: M3–M20 across flats, flange diameter, height, flange thickness + M5–M16 envelope files, isometric render of a generated part
Hex flange nuts, DIN 6923: M3–M20 across flats, flange diameter, height, flange thickness + M5–M16 envelope files34.5×34.5×16.0 mm★ 6 files
Square nuts, DIN 557: M5–M20 width across flats, thickness, corner distance + 8 envelope files, isometric render of a generated part
Square nuts, DIN 557: M5–M20 width across flats, thickness, corner distance + 8 envelope files24.0×24.0×13.0 mm★ 8 files

Questions

How tall is an M8 acorn nut?

15 mm overall (DIN 1587 high type), 13 mm across flats, dome diameter 12.5 mm max (fasten.it; Westfield agrees).

What wrench size is an M10 acorn nut?

16 mm, with 17 mm printed as an alternative on fasten.it (the s = 17 column in brackets).