|
Recommended tapping and clearance drill sizes
 |
| UNF Unified Fine Thread |
| d1 |
TPI |
d2 mm |
d3 mm |
|
d1 |
TPI |
d2 mm |
d3 mm |
| No 0 |
80 |
1.25 |
1.60 |
|
1/4 |
28 |
5.50 |
6.50 |
| No 1 |
72 |
1.55 |
1.95 |
|
5/16 |
24 |
6.90 |
8.10 |
| No 2 |
64 |
1.90 |
2.30 |
|
3/8 |
24 |
8.50 |
9.70 |
| No 3 |
56 |
2.15 |
2.65 |
|
7/16 |
20 |
9.90 |
11.30 |
| No 4 |
48 |
2.40 |
2.95 |
|
1/2 |
20 |
11.50 |
13.00 |
| No 5 |
44 |
2.70 |
3.30 |
|
9/16 |
18 |
12.90 |
14.50 |
| No 6 |
40 |
2.95 |
3.60 |
|
5/8 |
18/td>
| 14.50 |
16.25 |
| No 8 |
36 |
3.50 |
4.30 |
|
3/4 |
16 |
17.50 |
19.25 |
| No 10 |
32 |
4.10 |
4.90 |
|
7/8 |
14 |
20.40 |
22.50 |
| No 12 |
28 |
4.70 |
5.60 |
|
1 |
12 |
23.25 |
25.75 |
|
|
|
|
|
1 1/8 |
12 |
26.50 |
29.00 |
|
|
|
|
|
1 1/4 |
12 |
29.50 |
32.00 |
|
|
|
|
|
1 3/8 |
12 |
32.75 |
35.50 |
|
|
|
|
|
1 1/2 |
12 |
36.00 |
38.50 |
The above information is for guidence only and should not be used when working to stringent specifications.
|
