inch thread (unc)

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Pitch DiameterClass

Pitch DiameterMax.(3) Min. Min.(5) Max.(3) Min. Tolarence Min. Max. Min. Max. TolareMin.

1-64 or 0.073-64 UNC 1.854 0.397 2A 0.016 1.838 1.743 - 1.582 1.532 0.050 1.367 2B 1.425 1.582 1.598 1.663 0.065 1.8553A 0.000 1.854 1.758 - 1.597 1.560 0.037 1.382 3B 1.425 1.582 1.598 1.645 0.047 1.855

2-56 or 0.086-56 UNC 2.184 0.454 2A 0.016 2.169 2.066 - 1.874 1.822 0.052 1.631 2B 1.695 1.871 1.890 1.960 0.070 2.1853A 0.000 2.184 2.081 - 1.889 1.850 0.039 1.646 3B 1.695 1.871 1.890 1.943 0.053 2.185

3-48 or 0.099-48 UNC 2.514 0.529 2A 0.019 2.496 2.383 - 2.153 2.096 0.057 1.864 2B 1.941 2.146 2.172 2.247 0.075 2.5153A 0.000 2.514 2.401 - 2.171 2.129 0.042 1.882 3B 1.941 2.146 2.172 2.227 0.055 2.515

4-40 or 0.112-40 UNC 2.844 0.635 2A 0.021 2.824 2.695 - 2.413 2.350 0.063 2.068 2B 2.157 2.385 2.434 2.517 0.083 2.8453A 0.000 2.844 2.716 - 2.433 2.386 0.047 2.088 3B 2.157 2.385 2.434 2.494 0.060 2.845

5-40 or 0.125-40 UNC 3.175 0.635 2A 0.021 3.154 3.026 - 2.743 2.678 0.065 2.398 2B 2.487 2.697 2.764 2.847 0.083 3.1753A 0.000 3.175 3.046 - 2.763 2.716 0.047 2.418 3B 2.487 2.697 2.764 2.827 0.063 3.175

66-32 or 0.138-32 UNC 3.505 0.794 2A 0.021 3.484 3.333 - 2.969 2.899 0.070 2.540 2B 2.642 2.895 2.990 3.083 0.093 3.5063A 0.000 3.505 3.353 - 2.989 2.937 0.052 2.560 3B 2.642 2.895 2.990 3.058 0.068 3.506

8-32 or 0.164-32 UNC 4.165 0.794 2A 0.023 4.142 3.991 - 3.627 3.554 0.073 3.198 2B 3.302 3.530 3.650 3.746 0.096 4.1663A 0.000 4.165 4.014 - 3.649 3.595 0.054 3.221 3B 3.302 3.528 3.650 3.721 0.071 4.166

10-24 or 0.190-24 UNC 4.826 1.058 2A 0.026 4.800 4.618 - 4.112 4.029 0.083 3.541 2B 3.683 3.962 4.138 4.246 0.108 4.8263A 0.000 4.826 4.644 - 4.137 4.075 0.062 3.566 3B 3.683 3.949 4.138 4.218 0.080 4.826

12-24 or 0.216-24 UNC 5.486 1.058 2A 0.027 5.461 5.279 - 4.772 4.687 0.085 4.201 2B 4.344 4.597 4.799 4.909 0.110 5.4873A 0.000 5.486 5.304 - 4.798 4.733 0.065 4.227 3B 4.344 4.589 4.799 4.881 0.082 5.487

1/4-20 or 0.250-20 UNC 6.350 16.270 1A 0.029 6.322 6.013 - 5.496 5.355 0.141 4.811 1B 4.979 5.257 5.525 5.709 0.184 6.3502A 0.030 6.322 6.117 6.013 5.496 5.403 0.093 4.811 2B 4.979 5.257 5.525 5.648 0.123 6.3503A 6.000 6.350 6.145 - 5.524 5.454 0.070 4.839 3B 4.979 5.250 5.525 5.615 0.090 6.350

5/16-18 or 0.315-18 UNC 7.937 1.411 1A 0.031 7.907 7.575 - 6.990 6.836 0.154 6.228 1B 6.401 6.731 7.021 7.221 0.200 7.9382A 0.031 7.907 7.687 7.575 6.990 6.889 0.101 6.228 2B 6.401 6.731 7.021 7.155 0.134 7.9383A 0.000 7.937 7.717 - 7.020 6.945 0.075 6.259 3B 6.401 6.680 7.021 7.119 0.098 7.938

3/8-16 or 0.375-16 UNC 9.525 1.588 1A 0.034 9.491 9.132 - 8.460 8.296 0.164 7.600 1B 7.798 8.153 8.494 8.709 0.215 9.5252A 0.034 9.491 9.254 9.132 8.460 8.349 0.111 7.600 2B 7.798 8.153 8.494 8.638 0.144 9.5253A 0.000 9.525 9.287 - 8.493 8.410 0.083 7.633 3B 7.798 8.082 8.494 8.602 0.108 9.525

7/16-14 or 0.4375-14UNC 11.112 1.814 1A 0.036 11.076 10.684 - 9.898 9.719 0.179 8.918 1B 9.144 9.550 9.934 10.167 0.233 11.1132A 0.036 11.076 10.816 10.684 9.898 9.779 0.119 8.918 2B 9.144 9.550 9.934 10.088 0.154 11.1133A 0.000 11.112 10.851 - 9.933 9.846 0.087 8.954 3B 9.144 9.441 9.934 10.050 0.116 11.113

1/2-3 or 0.500-13 UNC 12.700 1.954 1A 0.038 12.661 12.248 - 11.392 11.204 0.188 8.430 1B 10.592 11.023 11.430 11.676 0.246 12.700

Nominal SizeT P I

External Minor Diameter UNRMax

Internal

Minor Diameter

MajorDia

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Pitch DiameterClass


Nominal SizeT P I


Internal

Minor Diameter

MajorDia

2A 0.038 12.661 12.386 12.248 11.392 11.265 0.127 8.430 2B 10.592 11.023 11.430 11.595 0.165 12.7003A 0.000 12.700 12.424 - 11.430 11.336 0.094 8.468 3B 10.592 10.881 11.430 11.551 0.121 12.700

9/16-12 or 0.5625-12UNC 14.287 2.117 1A 0.041 14.246 13.810 - 12.873 12.675 0.198 11.727 1B 11.989 12.446 12.914 13.172 0.258 14.2882A 0.041 14.246 13.958 13.810 12.873 12.741 0.132 11.727 2B 11.989 12.446 12.914 13.086 0.173 14.2883A 0.000 14.287 13.998 - 12.913 12.814 0.099 11.768 3B 11.989 12.301 12.914 13.042 0.128 14.288

5/8-11 or 0.625-11 UNC 15.875 2.309 1A 0.042 15.834 15.375 - 14.335 14.125 0.218 13.086 1B 13.386 13.868 14.377 14.648 0.271 15.8752A 0.042 15.834 15.528 125.373 14.335 14.197 0.138 13.086 2B 13.386 13.868 14.377 14.559 0.182 15.8753A 0.000 15.875 15.568 - 14.376 14.273 0.103 13.127 3B 13.386 13.693 14.377 14.513 0.136 15.875

3/4-10 or .0750-10 UNC 19.050 2.540 1A 0.046 19.004 18.512 - 17.353 17.130 0.223 15.979 1B 16.307 16.840 17.399 17.691 0.292 19.0502A 0.046 19.004 18.677 18.512 17.353 17.204 0.149 15.979 2B 16.307 16.840 17.399 17.594 0.195 19.0503A 0.000 19.050 18.273 - 17.399 17.288 0.111 16.025 3B 16.307 16.624 17.399 17.543 0.144 19.050

7/8-9 or 0.875-9 UNC 22.225 2.822 1A 0.050 22.176 21.649 - 20.342 20.102 0.240 18.816 1B 19.177 19.761 20.392 20.703 0.311 22.2252A 0.050 22.176 21.824 21.649 20.342 20.183 0.159 18.816 2B 19.177 19.761 20.392 20.599 0.207 22.2253A 0.000 22.225 21.872 - 20.390 20.272 0.119 18.865 3B 19.177 19.509 20.392 20.546 0.154 22.225

1-8 or 1.000-8 UNC 25.400 3.175 1A 0.052 25.349 24.778 - 23.286 23.031 0.255 21.570 1B 21.971 22.606 23.338 23.672 0.334 25.4002A 0.052 25.349 24.969 24.778 23.286 23.114 0.172 21.570 2B 21.971 22.606 23.338 23.561 0.223 25.4003A 0.000 25.400 25.019 - 23.337 23.208 0.129 21.620 3B 21.971 22.344 23.338 23.505 0.167 25.400

1-1/8 - 7 or 1.125-8 UNC 28.575 3.629 1A 0.056 28.519 27.895 - 26.162 25.886 0.276 24.199 1B 24.638 25.349 26.218 26.576 0.358 28.5752A 0.056 28.519 28.103 27.895 26.162 25.980 0.182 24.199 2B 24.638 25.349 26.218 26.456 0.238 28.5753A 0.000 25.575 28.159 - 26.217 26.081 0.136 24.254 3B 24.638 25.082 26.218 26.398 0.180 28.575

1-1/4 -7 or 1.250-7 UNC 31.750 3.629 1A 0.056 31.694 31.070 - 29.337 29.056 0.281 27.374 1B 27.813 28.524 29.393 29.758 0.365 31.7502A 0.056 31.694 31.278 31.070 29.337 29.150 0.187 27.374 2B 27.813 28.524 29.393 29.636 0.243 31.7503A 0.000 31.750 31.334 - 29.392 29.254 0.138 27.429 3B 27.813 28.257 29.393 29.575 0.182 31.750

1-3/8 -6 or 1.375-6 UNC 34.925 4.233 1A 0.062 34.864 34.171 - 32.113 31.809 0.304 29.825 1B 30.353 31.115 32.175 32.567 0.392 34.9252A 0.062 34.864 34.402 34.171 32.113 31.911 0.202 29.825 2B 30.353 31.115 32.175 32.438 0.263 34.9253A 0.000 34.925 34.463 - 32.174 31.022 0.152 29.886 3B 30.353 30.850 32.175 32.372 0.197 34.925

1-1/2 -6 or 1.500-6 UNC 38.100 4.233 1A 0.062 38.039 37.346 - 35.288 34.981 0.307 33.000 1B 33.528 34.290 35.350 35.750 0.400 38.1002A 0.062 38.039 37.577 37.346 35.288 35.083 0.205 33.000 2B 33.528 34.290 35.350 35.615 0.265 38.1003A 0.000 38.100 37.638 - 35.349 35.195 0.154 33.061 3B 33.528 34.025 35.350 35.549 0.199 38.100

1-3/4 -5 or 1.750-5 UNC 44.450 5.080 1A 0.070 44.381 43.600 - 41.081 40.742 0.339 38.334 1B 38.964 39.827 41.151 41.592 0.441 44.4502A 0.070 44.381 43.861 43.600 41.081 40.856 0.225 38.334 2B 38.964 39.827 41.151 41.445 0.294 44.450

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Pitch DiameterClass


Nominal SizeT P I


Internal

Minor Diameter

MajorDia

3A 0.000 44.450 43.930 - 41.150 40.981 0.169 38.403 3B 38.964 39.560 41.151 41.371 0.220 44.4502- 4-1/2 or 2.000-4.5 UNC 50.800 5.644 1A 0.074 50.726 49.889 - 47.061 46.698 0.363 44.003 1B 44.679 45.593 47.135 32.607 0.472 50.800

2A 0.074 50.726 50.168 49.889 47.061 46.820 0.241 44.003 2B 44.679 45.593 47.135 47.449 0.314 50.8003A 0.000 50.800 50.242 - 47.134 46.955 0.179 44.077 3B 44.679 45.366 47.135 47.371 0.236 50.800

2-1/4 - 4-1/2 or 2.25 UNC 57.150 5.644 1A 0.074 57.076 56.239 - 53.411 53.041 0.370 50.353 1B 51.029 51.943 53.485 53.967 0.482 57.1502A 0.074 57.076 56.518 56.239 53.411 53.165 0.246 50.353 2B 51.029 51.943 53.485 53.804 0.419 57.1503A 0.000 57.150 56.592 - 53.484 53.300 0.184 50.427 3B 51.029 51.716 53.485 53.726 0.141 57.150

2-1/2-4 or 2.500-4 UNC 63.500 6.350 1A 0.080 63.421 62.515 - 59.296 58.903 0.393 55.860 1B 56.617 57.581 59.376 59.888 0.512 63.5002A 0.080 63.421 62.817 62.515 59.296 59.033 0.263 55.860 2B 56.617 57.581 59.376 59.717 0.341 63.5003A 0.000 63.500 62.896 - 59.375 59.177 0.198 55.930 3B 56.617 57.388 59.376 59.631 0.255 63.500

2-3/2-4 or 2.750-4 UNC 69.850 6.350 1A 0.083 69.768 68.862 - 65.643 65.243 0.400 62.207 1B 62.967 63.931 65.726 66.248 0.522 69.8502A 0.083 69.768 69.165 68.862 65.643 65.378 0.265 62.207 2B 62.967 63.931 65.726 66.073 0.347 69.8503A 0.000 69.850 69.246 65.725 65.525 0.200 62.288 3B 62.967 63.738 65.726 65.986 0.260 69.850

3-4 or 3.000-4 UNC 76.200 6.350 1A 0.083 76.118 75.212 - 71.993 71.585 0.408 68.557 1B 69.317 70.281 72.076 72.605 0.529 76.2002A 0.083 76.118 75.515 75.212 71.993 71.722 0.271 68.557 2B 69.317 70.281 72.076 72.428 0.352 76.2003A 0.000 76.200 75.596 - 72.075 71.872 0.203 68.638 3B 69.317 70.088 72.076 72.339 0.263 76.200

3-1/4 - 4 or 3.250-4 UNC 82.550 6.350 1A 0.085 82.466 81.560 - 78.341 77.928 0.413 74.905 1B 75.667 76.631 78.426 78.963 0.537 82.5502A 0.085 82.466 81.862 81.560 78.341 78.065 0.276 74.905 2B 75.667 76.631 78.426 78.783 0.357 82.5503A 0.000 82.550 81.946 - 78.425 78.217 0.208 74.988 3B 75.667 76.438 78.426 78.694 0.268 82.550

3-1/2 - 4 or 3.500-4 UNC 88.900 6.350 1A 0.085 88.816 87.910 - 84.691 84.270 0.421 81.255 1B 82.017 82.981 84.776 85.321 0.545 88.9002A 0.085 88.816 88.212 87.910 84.691 84.412 0.279 81.255 2B 82.017 82.981 84.776 85.138 0.362 88.9003A 0.000 88.900 88.296 - 84.775 84.565 0.210 81.338 3B 82.017 82.788 84.776 85.049 0.273 88.900

3-3/4 - 4 or 3.750-4 UNC 95.250 6.350 1A 0.088 95.163 94.257 - 91.038 90.612 0.426 87.602 1B 88.367 89.331 91.126 91.678 0.552 95.2502A 0.088 95.163 94.560 94.257 91.038 90.755 0.283 87.602 2B 88.367 89.331 91.126 91.493 0.367 95.2503A 0.000 95.250 94.646 - 91.125 90.912 0.213 87.688 3B 88.367 89.138 91.126 91.401 0.275 95.250

4-4 - 4 or 4.00-4 UNC 101.600 6.350 1A 0.088 101.513 100.607 - 97.388 96.957 0.431 93.952 1B 94.717 95.681 97.476 98.036 0.560 101.6002A 0.088 101.513 100.910 100.607 97.388 97.102 0.286 93.952 2B 94.717 95.681 97.476 97.848 0.372 101.6003A 0.000 101.600 100.996 - 97.475 97.260 0.215 94.038 3B 94.717 95.488 97.476 97.756 0.280 101.600

inch thread (unc)

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