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Nylon-insert lock nuts, inch (ASME B18.16.6): 1/4 to 1-1/2 width across flats, across corners, height

What are the dimensions of a 1/4-20 or 3/8-16 nylon insert lock nut (nylock), and what wrench size does it take? · Standard part · basis: fasten.it's ASME B18.16.6 (2008) Table 1, inch series; numbers only

Also called: 1/4-20 nylock nut dimensions, 3/8-16 nylon insert lock nut size, nylock nut wrench size, 5/16-18 nyloc nut height, 1/2-13 nylon lock nut width across flats, asme b18.16.6 table, inch nyloc nut dimensions chart, 3/4-10 nylock nut

Exact dimensions. True size, with no tolerance added.

sizes
14 in table

Notes

  • Columns (inches unless stated): threads per inch for coarse (UNC) and fine (UNF) series; B max, C min, D min, E min as the page prints them without defining the letters. B max is the hex width: for 1/4 it is 0.44 in, the 7/16 in (0.4375) across-flats of a 1/4-20 hex nut on hex-nuts-inch, and C min (0.488 for 1/4) is a bit under the across-corners of a 7/16 hex (0.505), so B is read as width across flats and C as across corners. D min (0.298 for 1/4) and E min (0.225) are read as overall height and a lower height of the hex part, but the page does not say so; check the standard before relying on D and E.
  • The mm column is the nominal size. The 'overall height' of a nylon-insert nut (including the collar) is the number a pocket depth needs; check the maker's drawing for the nut you buy. No file: the collar profile is not published as numbers on the page read, and the hex-prism part is the same as hex-nuts-inch.
  • Metric nyloc nuts (ISO 7040, DIN 985): nylon-insert-lock-nuts-iso-7040-din-985 and nyloc-nuts-metric. McMaster-Carr sells thin, regular and heavy nylon-insert locknuts with per-part STEP; its category is linked, not copied.

Nylon-insert lock nuts, inch (ASME B18.16.6): 1/4 to 1-1/2 width… size chart

size (in)nominal (mm)UNC TPIUNF TPIB max (in)B max (mm)C min (in)D min (in)E min (in)
1/46.3520280.44011.180.4880.2980.225
5/167.9418240.50012.700.5570.3290.250
3/89.5316240.56014.220.6280.4380.335
7/1611.1114200.62715.930.6980.4380.324
1/212.713200.75019.050.8400.5790.464
9/1614.2912180.87722.280.9800.6260.469
5/815.8811180.94023.881.0500.7350.593
3/419.0510161.06026.921.1900.8600.742
7/822.239141.25031.751.4000.9690.790
125.48121.44036.581.6191.0160.825
1-1/828.587121.62741.331.8301.1410.930
1-1/431.757121.81546.102.0461.3601.125
1-3/834.936122.00050.802.2591.5471.282
1-1/238.16122.19755.802.4701.5781.313

Where the files are

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

fasten.itASME B18.16.6 nylon insert lock nuts, inch series (2008) Table 1: B max, C min, D min, E min; 1/4 to 1-1/2webReference page; numbers only. The page does not define the column letters
McMaster-CarrLocknuts (nylon-insert, thin and heavy profiles) (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=nylon-insert-lock-nuts-inch-asme-b18-16-6

length
Schematic, not to scale.

Fits with

Hex nuts, inch: #4-40 to 3/4-10 (ASME B18.2.2), isometric render of a generated part
Hex nuts, inch: #4-40 to 3/4-10 (ASME B18.2.2)12 sizes★ 12 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
Nyloc lock nuts, M2.5–M8 (DIN 985), isometric render of a generated part
Nyloc lock nuts, M2.5–M8 (DIN 985)6 sizes★ 6 files
Flat washers, inch: SAE and USS, 1/4 to 3/4 in (ASME B18.21.1 Type A), isometric render of a generated part
Flat washers, inch: SAE and USS, 1/4 to 3/4 in (ASME B18.21.1 Type A)14 sizes★ 14 files
Plain washers, inch Type B (narrow, regular, wide): #0 to 3 in ID, OD, thickness + 12 washer files, isometric render of a generated part
Plain washers, inch Type B (narrow, regular, wide): #0 to 3 in ID, OD, thickness + 12 washer files63.5×63.5×4.1 mm★ 12 files

Questions

What wrench size is a 3/8-16 nylock nut?

B max is 0.56 in (9/16 in) in the ASME B18.16.6 table at fasten.it, matching the 9/16 in hex nut on hex-nuts-inch.

How tall is a 1/4-20 nylon insert lock nut?

The table's D min is 0.298 in and E min 0.225 in; the page does not define the letters, so check the standard.