| Preference Class |
Pitch |
Drill Size
for
Tapping
M Coarse |
Drill Size
for
Tapping
M Fine |
| 1(1) |
2(2) |
Coarse |
Fine |
1
1.2
|
1.4
|
.25
.25
.3 |
|
.75
.95
1.1 |
|
1.6
2
|
1.8 |
.35
.35
.4 |
|
1.25
1.4
1.6
|
|
2.5
3
|
2.2
|
.45
.45
.5
|
|
1.7
2.0
2.5
|
|
4
5
|
3.5
|
.6
.7
.8
|
|
2.9
3.3
4.2
|
|
6
8 |
|
1
1.25 |
1 |
5.0
6.8 |
7 |
10
12 |
|
1.5
1.75 |
1.25
1.25 (1.5) |
8.5
10.2 |
8.8 (9.0)
10.8 (10.5) |
14
16
|
14
|
2
2
|
1.5
1.5 |
12.0
14.0 |
12.5
14.5 |
20
|
18
22 |
2.5
2.5
2.5
|
1.5
1.5
1.5 |
15.5
17.5
19.5
|
16.5
18.5
20.5
|
24
|
|
3
|
2 |
21.0 |
22.0 |
30 |
27
|
3
3.5 |
2
2 |
24.0
26.5 |
25.0
28.0 |
36
|
33
|
3.5
4 |
2
3 |
29.5
32.0 |
31.0
33.0 |
42
48
|
45
|
4.5
4.5
5
|
3
3
3 |
37.5
40.5
43.0
|
39.0
42.0
45.0
|
56
|
52
60 |
5
5.5
5.5 |
3
4
4 |
47.0
50.5
54.5 |
49.0
52.0
56.0 |
64
72
|
68
|
6
6
|
4
4
6
|
58.0
62.0
|
60.0
64.0
66.0 |
80
|
76
85 |
|
6
6
6 |
|
70.0
74.0
79.0 |
90
100
|
95
|
|
6
6
6 |
|
84.0
89.0
94.0
|
*All
dimensions listed in millimeters
(1) The fastener sizes in preference class 1 are
suggested to be used in all designs. The sizes in this category
are generally readily available.
(2) Fasteners in preference class 2 should
be chosen only if a size in preference class 1 is not feasible. For
preference class 2 sizes, longer
lead times should be expected.
|
