Nominal Size &
Threads / Inch &
Series Designation |
Allow-
ance |
Minor
Diameter |
Pitch
Diameter |
Major
Diameter |
|
|
|
Max. |
Min. |
Max. |
Min. |
Toleran-
ce |
Min. |
0-80
1-64
1-72
2-56
2-64 |
UNF
UNC
UNF
UNC
UNF |
0.0005
0.0006
0.0006
0.0006
0.0006 |
0.0465
0.0561
0.0580
0.0667
0.0691 |
0.0514
0.0623
0.0635
0.0737
0.0753 |
0.0519
0.0629
0.0640
0.0744
0.0759 |
0.0542
0.0655
0.0665
0.0772
0.0786 |
0.0023
0.0026
0.0025
0.0028
0.0027 |
0.0600
0.0730
0.0730
0.0860
0.0860 |
3-48
3-56
4-40
4-48
5-40
|
UNC
UNF
UNC
UNF
UNC |
0.0007
0.0007
0.0008
0.0007
0.0008 |
0.0764
0.0797
0.0849
0.0894
0.0979 |
0.0845
0.0865
0.0939
0.0968
0.1062 |
0.0855
0.0874
0.0958
0.0985
0.1088 |
0.0885
0.0902
0.0991
0.1016
0.1121 |
0.0030
0.0028
0.0033
0.0031
0.0033 |
0.0990
0.0990
0.1120
0.1120
0.1250 |
5-44
6-32
6-40
8-32
8-36 |
UNF
UNC
UNF
UNC
UNF |
0.0007
0.0008
0.0008
0.0009
0.0008 |
0.1004
0.104
0.111
0.130
0.134 |
0.1079
0.114
0.119
0.139
0.142 |
0.1102
0.1177
0.1218
0.1437
0.1460 |
0.1134
0.1214
0.1252
0.1475
0.1496 |
0.0032
0.0037
0.0034
0.0038
0.0036 |
0.1250
0.1380
0.1380
0.1640
0.1640 |
10-24
10-32
12-24
12-28
1/4-20 |
UNC
UNF
UNC
UNF
UNC |
0.0010
0.0009
0.0010
0.0010
0.0011 |
0.145
0.156
0.171
0.177
0.196 |
0.156
0.164
0.181
0.186
0.207 |
0.1629
0.1697
0.1889
0.1928
0.2175 |
0.1672
0.1736
0.1933
0.1970
0.2224 |
0.0043
0.0039
0.0044
0.0042
0.0049 |
0.1900
0.1900
0.2160
0.2160
0.2500 |
1/4-28
5/16-18
5/16-24
3/8-16
3/8-24 |
UNF
UNC
UNF
UNC
UNF |
0.0010
0.0012
0.0011
0.0013
0.0011 |
0.211
0.252
0.267
0.307
0.330 |
0.220
0.265
0.277
0.321
0.034 |
0.2268
0.2764
0.2854
0.3344
0.3479 |
0.2311
0.2817
0.2902
0.3401
0.3528 |
0.0043
0.0053
0.0048
0.0057
0.0049 |
0.2500
0.3125
0.3125
0.3750
0.3750 |
7/16-14
7/16-20
1/2-13
1/2-20
9/16-12 |
UNC
UNF
UNC
UNF
UNC |
0.0014
0.0013
0.0015
0.0013
0.0016 |
0.360
0.383
0.417
0.446
0.472 |
0.376
0.395
0.434
0.457
0.490 |
0.3911
0.4050
0.4500
0.4675
0.5084 |
0.3972
0.4104
0.4565
0.4731
0.5152 |
0.0061
0.0054
0.0065
0.0056
0.0068 |
0.4375
0.4375
0.5000
0.5000
0.5625 |
9/16-18
5/8-11
5/8-18
3/4-10
3/4-16 |
UNF
UNC
UNF
UNC
UNF |
0.0014
0.0016
0.0014
0.0018
0.0015 |
0.502
0.527
0.565
0.642
0.682 |
0.515
0.546
0.578
0.663
0.696 |
0.5264
0.5660
0.5889
0.6850
0.7094 |
0.5323
0.5732
0.5949
0.6927
0.7159 |
0.0059
0.0072
0.0060
0.0077
0.0065 |
0.5625
0.6250
0.6250
0.7500
0.7500 |
7/8-9
7/8-14
1-8
1-12
1-14 |
UNC
UNF
UNC
UNF
UNS |
0.0019
0.0016
0.0020
0.0018
0.0017 |
0.755
0.798
0.865
0.910
0.923 |
0.778
0.814
0.890
0.928
0.938 |
0.8028
0.8286
0.9188
0.9459
0.9536 |
0.8110
0.8356
0.9276
0.9535
0.9609 |
0.0082
0.0070
0.0088
0.0076
0.0073 |
0.8750
0.8750
1.0000
1.0000
1.0000 |
11/8-7
11/8-8
11/812
11/4-7
11/4-8 |
UNC
UN
UNF
UNC
UN |
0.0022
0.0021
0.0018
0.022
0.0021 |
0.970
0.990
1.035
1.095
1.115 |
0.998
1.015
1.053
1.123
1.140 |
1.322
1.0438
1.0709
1.1572
1.1688 |
1.0416
0.0528
1.0787
1.668
1.1780 |
0.0094
0.0090
0.0078
0.0096
0.0092 |
1.1250
1.1250
1.1250
1.2500
1.2500 |
11/4-12
1 3/8-6
1 3/8-8
1 3/8-12
11/2-6 |
UNF
UNC
UN
UNF
UNC |
0.0018
0.0024
0.0022
0.0019
0.0024 |
1.160
1.195
1.240
1.285
1.320 |
1.178
1.225
1.265
1.303
1.350 |
1.1959
1.2667
1.2938
1.3209
1.3917 |
1.2039
1.2771
1.3031
1.3291
1.4022 |
0.0080
0.0104
0.0093
0.0082
0.0105 |
1.2500
1.3750
1.3750
1.3750
1.5000 |
11/2-8
11/2-12
1 5/8-8
1 3/4-5
1 3/4-8 |
UN
UNC
UN
UNC
UN |
0.0022
0.0019
0.0022
0.0027
0.0023 |
1.365
1.410
1.490
1.534
1.615 |
1.390
1.428
1.515
1.568
1.640 |
1.4188
1.4459
1.5438
1.6201
1.6688 |
1.4283
1.4542
1.5535
1.6317
1.6786 |
0.0095
0.0083
0.0097
0.0116
0.0098 |
1.5000
1.5000
1.6250
1.7500
1.7500 |
1 7/8-8
2-41/2
2-8
2 1/4-4.5
2 1/4-8 |
UN
UNC
UN
UNC
UN |
0.0023
0.0029
0.0023
0.0029
0.0024 |
1.740
1.759
1.865
2.009
2.115 |
1.765
1.795
1.890
2.045
2.140 |
1.7938
1.8557
1.9188
2.1057
2.1688 |
1.8038
1.8681
1.9289
2.1183
2.1792 |
0.0100
0.0124
0.0101
0.0126
0.0104 |
1.8750
2.0000
2.0000
2.2500
2.2500 |
2 1/2-4
2 1/2-8
2 3/4-4
2 3/4-8
3-4 |
UNC
UN
UNC
UN
UNC |
0.0031
0.0024
0.0032
0.0025
0.0032 |
2.229
2.365
2.479
2.615
2.729 |
2.267
2.390
2.517
2.640
2.767 |
2.3376
2.4188
2.5876
2.6688
2.8376 |
2.3511
2.4294
2.6013
2.6796
2.8515 |
0.0135
0.0106
0.0137
0.0108
0.0139 |
2.5000
2.5000
2.7500
2.7500
3.0000 |
3-8
3 1/4-4
31/4-8
3 1/2-4
31/2-8 |
UN
UNC
UN
UNC
UN |
0.0026
0.0033
0.0026
0.0033
0.0026 |
2.865
2.979
3.115
3.229
3.365 |
2.890
3.017
3.140
3.267
3.390 |
2.9188
3.0876
3.1688
3.3376
3.4188 |
2.9299
3.1017
3.1801
3.3519
3.4303 |
0.0111
0.0141
0.0113
0.0143
0.0115 |
3.0000
3.2500
3.2500
3.5000
3.5000 |
3 3/4-4
3 3/4-8
4-4
4-8 |
UNC
UN
UNC
UN |
0.0034
0.0027
0.0034
0.0027 |
3.479
3.615
3.729
3.865 |
3.517
3.640
3.767
3.890 |
3.5876
3.6688
3.8376
3.9188 |
3.6021
3.6805
3.8523
3.9307 |
0.0145
0.0117
0.0147
0.0119 |
3.7500
3.7500
4.0000
4.0000 |