PRODUCT CATALOG
Socket Head Cap ScrewsFlat Head Socket Cap ScrewsButton Head Socket Cap ScrewsLow Head Socket Cap ScrewsSocket Head Shoulder BoltsSocket Head Set ScrewsSquare Head Set ScrewsStainless Socket Head FastenersMetric Socket Head FastenersHi Collar Lock WashersDowel PinsSocket Pressure PlugsSocket Hex Keys Standard & Metric
INFORMATION
YOUR CART
External Thread Dimensions for Screws
| External Threads for Machine Screws and SEMS & ASME B 1.1 | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Nominal Size & Threads per Inch |
Series Designation |
Allowance | Major Diameter | Pitch Diameter | Stress Area in2 |
Tensile Strength*, lb., min |
|||
| Max | Min | Max | Min | Tolerance | |||||
| 0-80 0.060 | UNF | .0005 | .0595 | .0563 | .0514 | .0496 | .0018 | - | |
| 1-64 0.073 | UNC | .0006 | .0724 | .0686 | .0623 | .0603 | .0020 | - | |
| 2-56 0.086 | UNC | .0006 | .0854 | .0813 | .0738 | .0717 | .0021 | - | |
| 3-48 0.099 | UNC | .0007 | .0983 | .0938 | .0848 | .0825 | .0023 | - | |
| 4-40 0.112 | UNC | .0008 | .1112 | .1061 | .0950 | .0925 | .0025 | 0.00604 | |
| 5-40 0.125 | UNC | .0008 | .1242 | .1191 | .1080 | .1054 | .0026 | 0.00796 | |
| 6-32 0.138 | UNC | .0008 | .1372 | .1312 | .1169 | .1141 | .0028 | .00909 | |
| 8-32 0.164 | UNC | .0009 | .1631 | .1571 | .1428 | .1399 | .0029 | 0.0140 | |
| 10-24 0.190 | UNC | .0010 | .1890 | .1818 | .1619 | .1586 | .0033 | 0.0175 | |
| 10-32 0.190 | UNF | .0009 | .1891 | .183 | .1688 | .1658 | .0030 | 0.0100 | |
| 12-24 0.216 | UNC | .0010 | .2150 | .2078 | .1879 | .1845 | .0034 | 0.0242 | |
| 1/4-20 0.250 | UNC | .0011 | .2489 | .2408 | .2164 | .2127 | .0037 | 0.0318 | |
| 1/4-28 .250 | UNF | .0010 | .2490 | .2425 | .2258 | .2225 | .0033 | 0.0364 | |
| 5/16-18 0.312 | UNC | .0012 | .3113 | .3026 | .2752 | .2712 | .0040 | .0524 | |
| 3/8-16 0.375 | UNC | .0013 | .3737 | .3643 | .3331 | .3287 | .0044 | .0775 | |
| 1/2-13 0.500 | UNC | .0015 | .4985 | .4876 | .4485 | .4435 | .0050 | .1419 | |
| Tolerance on Length L |
Nominal Screw Size |
Nominal Screw Length | |||
| Up to 1/2 in, incl. | Over 1/2 to 1 in, incl. | Over 1 to 2 in., incl. | Over 2 in. | ||
| 0 thru 12 | -0.02 | -0.03 | -0.06 | -0.09 | |
| 1/4 thru 3/4 | -0.03 | -0.03 | -0.06 | -0.09 | |