This table contains dimensions of round headed machine screws ranging in thread size from 0 to 3/4 inch nominal diameter.
This table includes maximum and minimum screw head diameter and height, slot width and depth as well as maximum screw shaft diameter information.
NOTES: All dimensions are in inches. Head dimensions for sizes 7/16 in and larger are in agreement with round-head cap screw dimensions except the minimum values have been decreased to provide tolerances in proportion to balance of table. The diameter of the unthreaded portion of machine screws shall not be less than the minimum pitch diameter nor more than the maximum major diameter of the thread. The radius of the fillet at the base of the head shall not exceed one- half the pitch of the screw thread.
D A H J T
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Max Head Diameter Height of head Width of slot Depth of slot
Nominal diameter ------------- -------------- ------------- -------------
size of screw Max Min Max Min Max Min Max Min
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0 0.060 0.113 0.099 0.053 0.043 0.023 0.016 0.039 0.029
1 0.073 0.138 0.122 0.061 0.051 0.026 0.019 0.044 0.033
2 0.086 0.162 0.146 0.069 0.059 0.031 0.023 0.048 0.037
3 0.099 0.187 0.169 0.078 0.067 0.035 0.027 0.053 0.040
4 0.112 0.211 0.193 0.086 0.075 0.039 0.031 0.058 0.044
5 0.125 0.236 0.217 0.095 0.083 0.043 0.035 0.063 0.047
6 0.138 0.260 0.240 0.103 0.091 0.048 0.039 0.068 0.051
8 0.164 0.309 0.287 0.120 0.107 0.054 0.045 0.077 0.058
10 0.190 0.359 0.334 0.137 0.123 0.060 0.050 0.087 0.065
12 0.216 0.408 0.382 0.153 0.139 0.067 0.056 0.096 0.072
1/4 0.250 0.472 0.443 0.175 0.160 0.075 0.064 0.109 0.082
5/16 0.3125 0.590 0.557 0.216 0.198 0.084 0.072 0.132 0.099
3/8 0.375 0.708 0.670 0.256 0.237 0.094 0.081 0.155 0.117
7/16 0.4375 0.750 0.707 0.328 0.307 0.094 0.081 0.196 0.148
1/2 0.500 0.813 0.766 0.355 0.332 0.106 0.091 0.211 0.159
9/16 0.5625 0.938 0.887 0.410 0.385 0.118 0.102 0.242 0.183
5/8 0.625 1.000 0.944 0.438 0.411 0.133 0.116 0.258 0.195
3/4 0.750 1.250 1.185 0.547 0.516 0.149 0.131 0.320 0.242
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