Finished Hex Nuts

Finished hex nuts are the most common type of nut. Finished refers to the dimensional standard. Except for some smaller sizes, the width across the flats of the hex is one-and-a-half times the nominal diameter. Thickness of finished hex nuts is approximately 90% of the nominal diameter. In modern terminology, these parts are usually referred to as regular nuts or simply hex nuts. However, as we at Nickel Systems are old-timers in the fastener business, we still refer to these parts as finished hex nuts.

Dimensions


Nominal Size	Basic Major Diameter of Thread	F		G		H		Maximum Runout of Bearing Surface to Thread Axis, FIM (Specified Proof Load)
		Width Across Flats		Width Across Corners		Thickness Hex Nuts
		Min	Max	Min	Max	Min	Max	Up to 150,000 psi	150,000 psi and Greater
1/4	0.2500	0.428	0.438	0.488	0.505	0.212	0.226	0.015	0.010
5/16	0.3125	0.489	0.500	0.557	0.577	0.258	0.273	0.016	0.011
3/8	0.3750	0.551	0.563	0.628	0.650	0.320	0.337	0.017	00.012
7/16	0.4375	0.675	0.688	0.768	0.794	0.365	0.385	0.018	0.013
1/2	0.5000	0.736	0.750	0.840	0.866	0.427	0.448	0.019	0.014
9/16	0.5625	0.861	0.875	0.982	1.010	0.473	0.496	0.020	0.015
5/8	0.6250	0.922	0.938	1.051	1.083	0.535	0.559	0.021	0.016
3/4	0.7500	1.088	1.125	1.240	1.299	0.617	0.665	0.023	0.018
7/8	0.8750	1.269	1.312	1.447	1.516	0.724	0.776	0.025	0.020
1	1.0000	1.450	1.500	1.653	1.732	0.831	0.887	0.027	0.022
1-1/8	1.1250	1.631	1.688	1.859	1.949	0.939	0.999	0.030	0.025
1-1/4	1.2500	1.812	1.875	2.066	2.165	1.030	1.094	0.033	0.028
1-3/8	1.3750	1.994	2.062	2.273	2.382	1.138	1.206	0.036	0.031
1-1/2	1.5000	2.175	2.250	2.480	2.598	1.245	1.317	0.039	0.034
1-5/8	1.6250	2.35	2.43	2.679	2.805	1.364	1.416	0.044	0.038
1-3/4	1.7500	2.538	2.625	2.893	3.031	1.460	1.540	0.048	0.041
1-7/8	1.8750	2.722	2.813	3.103	3.247	1.567	1.651	0.051	0.044
2	2.0000	2.900	3.0000	3.306	3.464	1.675	1.763	0.055	0.047
2-1/4	2.2500	3.263	3.375	3.719	3.897	1.890	1.986	0.061	0.052
2-1/2	2.500	3.625	3.750	4.133	4.330	2.105	2.209	0.068	0.058
2-3/4	2.7500	3.988	4.125	4.546	4.763	2.319	2.431	0.074	0.064
3	3.000	4.350	4.500	4.959	5.196	2.534	2.654	0.081	0.070
3-1/4	3.2500	4.713	4.875	5.373	5.629	2.749	2.877	0.087	0.075
3-1/2	3.500	5.075	5.250	5.786	6.062	2.964	3.100	0.094	0.081
3-3/4	3.7500	5.438	5.625	6.199	6.495	3.178	3.322	0.100	0.087
4	4.0000	5.800	6.000	6.612	6.928	3.393	3.545	0.107	0.093