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Dimensions of Go and No go Gages for Hexagon Sockets per. ASME B18.3
Hexagon sockets in screws shall allow the GO member of the gage to enter freely to the minimum key engagement depths specified in the dimensional tables for the respective screw types.
For hexagon sockets that are not chamfered, the NO GO gage member shall not enter any of the three across flat dimensions of the socket for nominal socket sizes of 1⁄8 in. and larger, and the hexagonal NO GO gage member shall not enter the socket for nominal socket sizes smaller than 1⁄8 in.
For chamfered hexagon sockets, the NO GO gage member shall be permitted to enter only to a depth equivalent to 10% of the nominal socket size for nominal socket sizes up to and including 1⁄16 in., and to 7.5% of the nominal socket sizes for larger sockets.
Dimension units in inches.
Related:
Socket Head Cap Head Screws Size Table
Nom. Socket Size | Go Gage Across Flats A | Go Gage AcrossWidth Corners B | Min. GO Gage Length C | Minimum Usable Gage Length D | No Go Gage Width E | No Go Gage Thichness F | No Go Gage Width Across Corners G | ||||||
Max. | Min. | Max. | Min. | Max. | Min. | Max. | Min. | Max. | Min. | ||||
- | 0.028 | 0.0281 | 0.0280 | 0.0316 | 0.0314 | 0.062 | 0.062 | 0.0285 | 0.0284 | - | - | 0.0308 | 0.0303 |
- | 0.035 | 0.0351 | 0.0350 | 0.0395 | 0.0393 | 0.093 | 0.093 | 0.0355 | 0.0354 | - | - | 0.0386 | 0.0381 |
- | 0.050 | 0.0501 | 0.0500 | 0.0562 | 0.0560 | 0.187 | 0.187 | 0.0510 | 0.0509 | - | - | 0.0550 | 0.0545 |
1⁄16 | 0.062 | 0.0626 | 0.0625 | 0.0703 | 0.0701 | 0.187 | 0.187 | 0.0635 | 0.0634 | - | - | 0.0688 | 0.0683 |
5⁄64 | 0.078 | 0.0782 | 0.0781 | 0.0882 | 0.0880 | 0.187 | 0.187 | 0.0791 | 0.0790 | - | - | 0.0862 | 0.0857 |
3⁄32 | 0.094 | 0.0939 | 0.0937 | 0.1060 | 0.1058 | 0.250 | 0.250 | 0.0952 | 0.0950 | - | - | 0.1036 | 0.1031 |
7⁄64 | 0.109 | 0.1096 | 0.1094 | 0.1240 | 0.1238 | 0.250 | 0.250 | 0.1111 | 0.1109 | - | - | 0.1212 | 0.1207 |
1⁄8 | 0.125 | 0.1252 | 0.1250 | 0.1420 | 0.1418 | 0.250 | 0.250 | 0.1270 | 0.1268 | 0.057 | 0.055 | - | - |
9⁄64 | 0.141 | 0.1408 | 0.1406 | 0.1595 | 0.1593 | 0.250 | 0.250 | 0.1426 | 0.1424 | 0.064 | 0.062 | - | - |
5⁄32 | 0.156 | 0.1564 | 0.1562 | 0.1776 | 0.1774 | 0.250 | 0.250 | 0.1587 | 0.1585 | 0.071 | 0.069 | - | - |
3⁄16 | 0.188 | 0.1877 | 0.1875 | 0.2137 | 0.2135 | 0.250 | 0.375 | 0.1900 | 0.1898 | 0.088 | 0.086 | - | - |
7⁄32 | 0.219 | 0.2189 | 0.2187 | 0.2492 | 0.2490 | 0.250 | 0.437 | 0.2217 | 0.2215 | 0.102 | 0.100 | - | - |
1⁄4 | 0.250 | 0.2502 | 0.2500 | 0.2848 | 0.2845 | 0.312 | 0.500 | 0.2530 | 0.2528 | 0.117 | 0.115 | - | - |
5⁄16 | 0.312 | 0.3127 | 0.3125 | 0.3573 | 0.3570 | 0.312 | 0.625 | 0.3160 | 0.3158 | 0.150 | 0.148 | - | - |
3⁄8 | 0.375 | 0.3752 | 0.3750 | 0.4288 | 0.4285 | 0.500 | 0.750 | 0.3790 | 0.3788 | 0.180 | 0.178 | - | - |
7⁄16 | 0.438 | 0.4377 | 0.4375 | 0.5008 | 0.5005 | 0.500 | 0.875 | 0.4420 | 0.4418 | 0.211 | 0.209 | - | - |
1⁄2 | 0.500 | 0.5002 | 0.5000 | 0.5718 | 0.5715 | 0.500 | 1.000 | 0.5050 | 0.5048 | 0.241 | 0.239 | - | - |
9⁄16 | 0.562 | 0.5627 | 0.5625 | 0.6424 | 0.6420 | 0.750 | 1.125 | 0.5680 | 0.5678 | 0.269 | 0.267 | . . . | . . . |
5⁄8 | 0.625 | 0.6252 | 0.6250 | 0.7150 | 0.7146 | 0.750 | 1.250 | 0.6310 | 0.6308 | 0.302 | 0.300 | . . . | . . . |
3⁄4 | 0.750 | 0.7502 | 0.7500 | 0.8585 | 0.8580 | 0.750 | 1.500 | 0.7570 | 0.7568 | 0.364 | 0.362 | . . . | . . . |
7⁄8 | 0.875 | 0.8752 | 0.8750 | 1.0025 | 1.0020 | 0.875 | 1.750 | 0.8850 | 0.8848 | 0.423 | 0.421 | . . . | . . . |
1 | 1.000 | 1.0002 | 1.0000 | 1.1475 | 1.1470 | 1.000 | 2.000 | 1.0200 | 1.0198 | 0.489 | 0.487 | . . . | . . . |
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