|Table of Contents |Section Contents|
(By permission from Vallory H. Laughner and Augustus D. Hargan, "Handbook of Fastening and Joining of Metal Parts," McGraw-Hill Company, New York, 1956.)
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
------ ------------- -------------- ------------- -------------
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
------- -------- ----- ----- ----- ----- ----- ----- ----- -----
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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