BS1083 Castle Nuts


 Across Flat Overall
Thickness		 Unslotted
Thickness		 Slot
Width		 Washer
Diameter

s m w n b

max min max min max min max min max min
1/4 0.445 0.438 0.290 0.280 0.200 0.190 0.100 0.090 0.428 0.418
5/16 0.525 0.518 0.340 0.330 0.250 0.240 0.100 0.090 0.508 0.498
3/8 0.600 0.592 0.402 0.392 0.312 0.302 0.100 0.090 0.582 0.572
7/16 0.710 0.702 0.515 0.505 0.375 0.365 0.135 0.125 0.690 0.680
1/2 0.820 0.812 0.577 0.567 0.437 0.427 0.135 0.125 0.800 0.790
9/16 0.920 0.912 0.687 0.677 0.500 0.490 0.175 0.165 0.900 0.890
5/8 1.010 1.000 0.749 0.739 0.562 0.552 0.175 0.165 0.985 0.975
3/4 1.200 1.190 0.921 0.911 0.687 0.677 0.218 0.208 1.175 1.165
7/8 1.300 1.288 0.984 0.974 0.750 0.740 0.218 0.208 1.273 1.263
1 1.480 1.468 1.155 1.145 0.875 0.865 0.260 0.250 1.453 1.443
1.1/8 1.670 1.640 1.280 1.270 1.000 0.990 0.260 0.250 1.620 1.610
1.1/4 1.860 1.815 1.453 1.433 1.125 1.105 0.300 0.290 1.795 1.785
1.3/8 2.050 2.005 1.578 1.558 1.250 1.230 0.300 0.290 1.985 1.975
1.1/2 2.220 2.175 1.703 1.683 1.375 1.355 0.300 0.290 2.155 2.145
1.3/4 2.580 2.520 2.000 1.980 1.625 1.605 0.343 0.333 2.495 2.485
2 2.760 2.700 2.218 2.198 1.750 1.730 0.426 0.416 2.675 2.665

It is at our discretion if the bottom of the slots are rounded or flat.

Washer faced nuts typical washer thickness = 0.015"