Self Tapping Screws - thread geometry

 

All dimensions in mm unless otherwise stated.

 

 

Metric

d1 - Minor thread diameter male

d2 - Minor thread diameter female

p - Pitch
 
Nominal size Pitch Major diameter Minor diameter
max min max min
2.2 0.8 2.24 2.1 1.63 1.52
2.9 1.1 2.9 2.76 2.18 2.08
3.5 1.3 3.53 3.35 2.64 2.51
3.9 1.4 3.91 3.73 2.92 2.77
4.2 1.4 4.22 4.04 3.1 2.95
4.8 1.6 4.8 4.62 3.58 3.43
5.5 1.8 5.46 5.28 4.17 3.99
6.3 1.8 6.25 6.03 4.88 4.7
 

 

Inch

d1 - Minor thread diameter male

d2 - Minor thread diameter female
 
Screw Threads per inch Major diameter Minor diameter
max min max min
No. 2 32 0.088 0.083 0.064 0.06
No. 4 24 0.114 0.109 0.086 0.082
No. 6 20 0.139 0.132 0.104 0.099
No. 7 19 0.154 0.147 0.115 0.109
No. 8 18 0.166 0.159 0.122 0.116
No. 10 16 0.189 0.182 0.141 0.135
No. 12 14 0.215 0.208 0.164 0.157
No. 14 14 0.246 0.237 0.192 0.185