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BA threads: tapping and clearance drills table

BA
no.
Tapping size drill
Clearance size
drill
mm
Number or
fraction size
mm
Number, letter
or fraction size
0
5.10
8
6.10
D
1
4.50
16
5.50
2
2
4.00
22
4.85
10
3
3.40
29
4.25
18
4
3.00
32
3.75
24
5
2.65
37
3.30
29
6
2.30
43
2.90
32
7
2.05
45/46
2.60
36
8
1.80
50
2.25
41
9
1.55
53
1.95
45
10
1.40
54
1.75
49
11
1.20
56
1.60
52
12
1.05
59
1.40
54
13
0.98
62
1.30
55
14
0.78
68
1.10
57
15
0.70
70
0.98
60
16
0.60
73
0.88
65