Threads and Points For Type F Thread Cutting Screws ANSI/ASME B18.6.4 1981 Nominal Size Threads Per Inch Major Dia.(D) Point Dia.(P) Point Taper Length(S) Determinant Length For Point Taper(L) Minimum
Practical Nominal Screw Lengths(L) Short Screws Long Screws 90° Heads Csk Heads 90° Heads Csk Heads 2 56 .0860 .0813 .068 .061 .062 .045 .080 .062 5/32 3/16 5/32 3/16 4 40 .1120 .1061 .087 .078 .088 .062 .112 .088 7/32 1/4 3/16 1/4 6 32 .1380 .1312 .107 .096 .109 .078 .141 .109 1/4 5/16 1/4 5/16 8 32 .1640 .1571 .132 .122 .109 .078 .141 .109 1/4 11/32 1/4 5/16 10 24 .1900 .1818 .148 .135 .146 .104 .188 .146 11/32 7/16 5/16 13/32 10 32 .1900 .1831 .158 .148 .109 .078 .141 .109 1/4 11/32 1/4 5/16 12 24 .2160 .2078 .174 .161 .146 .104 .188 .146 11/32 7/16 5/16 13/32 1/4 20 .2500 .2408 .200 .184 .175 .125 .225 .175 13/32 17/32 3/8 1/2 5/16 18 .3125 .3026 .257 .239 .194 .139 .250 .194 15/32 19/32 7/16 9/16 3/8 16 .3750 .3643 .312 .293 .219 .156 .281 .219 1/2 11/16 15/32 5/8
Max
Min
Max
Min
Max
Min
Max
Min
Suggest
Test Plate Thickness & Hole Sizes for Types 1, 23 & F | |||||
Nominal Size |
Thickness |
Hole Size | |||
Gage |
Max |
Min |
Drill Size |
Hole Dia. | |
2-56 |
18 |
.0800 |
.0760 |
49 |
.0730 |
4-40 |
18 |
.1110 |
.1070 |
41 |
.0960 |
5-40 |
18 |
.1110 |
.1070 |
37 |
.1010 |
6-32 |
14 |
.1425 |
.1385 |
31 |
.1200 |
8-32 |
14 |
.1905 |
.1845 |
26 |
.1470 |
10-24 |
1/8 |
.1905 |
.1845 |
17 |
.1730 |
10-32 |
1/8 |
.1905 |
.1845 |
16 |
.1770 |
12-24 |
1/8 |
.1905 |
.1845 |
8 |
.1990 |
¼-20 |
3/16 |
.2530 |
.2470 |
1 |
.2280 |
5/16-18 |
3/16 |
.3155 |
.3095 |
L |
.2900 |
3/8-16 |
3/16 |
.3780 |
.3720 |
T |
.3580 |
½-13 |
3/16 |
.4710 |
.4430 |
29/64 |
.4531 |