|
FRACTIONAL SIZE MACHINE SCREWS
TAP DRILL AND CLEARANCE DRILL SIZES
|
SCREW SIZE |
THREADS PER INCH |
DRILL SIZES |
|
No. |
O.D. |
N.C. |
N.F. |
TAP |
CLEAR |
|
1/4 |
.250 |
20 |
|
#7 |
17/64 |
|
1/4 |
.250 |
|
28 |
#3 |
17/64 |
|
5/16 |
.312 |
18 |
|
F |
21/64 |
|
5/16 |
.312 |
|
24 |
I |
21/64 |
|
3/8 |
.375 |
16 |
|
5/16 |
25/64 |
|
3/8 |
.375 |
|
24 |
Q |
25/64 |
|
7/16 |
.437 |
14 |
|
U |
29/64 |
|
7/16 |
.437 |
|
20 |
25/64 |
29/64 |
|
1/2 |
.500 |
13 |
|
27/64 |
33/64 |
|
1/2 |
.500 |
|
20 |
29/64 |
33/64 |
|
9/16 |
.562 |
12 |
|
31/64 |
37/64 |
|
9/16 |
.562 |
|
18 |
33/64 |
37/64 |
|
5/8 |
.625 |
11 |
|
17/32 |
41/64 |
|
5/8 |
.625 |
|
18 |
37/64 |
41/64 |
|
3/4 |
.750 |
10 |
|
21/32 |
49/64 |
|
3/4 |
.750 |
|
16 |
11/16 |
49/64 |
|
7/8 |
.875 |
9 |
|
49/64 |
57/64 |
|
7/8 |
.875 |
|
14 |
13/16 |
57/64 |
|
1 |
1.000 |
8 |
|
7/8 |
1 1/4 |
|
1 |
1.000 |
|
14 |
15/16 |
1 1/4 |
Note:
Tap Drill Sizes shown give approximately 75% depth of
thread.
|
