Jobber Drill, No.78, Normal Helix, High Speed Steel, Black Oxide

These High Speed Steel (HSS) Number Sizes Series J100 of jobber drills are general purpose drills for steels, cast steel, grey cast iron, malleable cast iron, nickel brass, aluminium alloy and graphite. Available in ana array of number sizes, the drills have a black oxide finish, a point angle of 118°, a normal helix angle, a standard web thickness, a relief angle of 8° - 20°, a tolerance of diameter of h8 and a tolerance of shank of f11.

Features and Benefits
• Available in an array of number sizes to suit your needs
• Manufactured from High Speed Steel (HSS) for optimum resilience
• Black oxide finish bolsters durability
• Industrial quality for versatility of use

Typical Applications
• Suited for drilling steels, cast steel, grey cast iron, malleable cast iron, nickel brass, aluminium alloy and graphite

Standards
• ANSI B328
• BS 328
• DIN 338

Notes
Gauge inch mm
80 0.014 0.343
79 0.015 0.368
78 0.016 0.406
77 0.018 0.457
76 0.020 0.508
75 0.021 0.533
74 0.023 0.572
73 0.024 0.610
72 0.025 0.635
71 0.026 0.660
70 0.028 0.711
69 0.029 0.742
68 0.031 0.787
67 0.032 0.813
66 0.033 0.838
65 0.035 0.889
64 0.036 0.914
63 0.037 0.940
62 0.038 0.965
61 0.039 0.991
60 0.040 1.016
59 0.041 1.041
58 0.042 1.067
57 0.043 1.092
56 0.046 1.181
55 0.052 1.321
54 0.055 1.397
53 0.059 1.511
52 0.064 1.613
51 0.067 1.702
50 0.070 1.778
49 0.073 1.854
48 0.076 1.930
47 0.079 1.994
46 0.081 2.057
45 0.082 2.083
44 0.086 2.184
43 0.089 2.261
42 0.094 2.375
41 0.096 2.438
40 0.098 2.489
39 0.099 2.527
38 0.101 2.578
37 0.104 2.642
36 0.106 2.705
35 0.110 2.794
34 0.111 2.819
33 0.113 2.870
32 0.116 2.946
31 0.120 3.048
30 0.129 3.264
29 0.136 3.454
28 0.141 3.569
27 0.144 3.658
26 0.147 3.734
25 0.149 3.797
24 0.152 3.861
23 0.154 3.912
22 0.157 3.988
21 0.159 4.039
20 0.161 4.089
19 0.166 4.216
18 0.169 4.305
17 0.173 4.394
16 0.177 4.496
15 0.180 4.572
14 0.182 4.623
13 0.185 4.699
12 0.189 4.801
11 0.191 4.851
10 0.194 4.915
9 0.196 4.978
8 0.199 5.055
7 0.201 5.105
6 0.204 5.182
5 0.206 5.220
4 0.209 5.309
3 0.213 5.410
2 0.221 5.613
1 0.228 5.791