The following is summarized from the American National Standard Keys and Keyways for Milling Cutters and Arbors ANSI/ASME B94.19-1997
Shaft and Arbor Class E and F
Nominal Shaft (Arbor) and Keyseat Cutter Hole Diameter |
Nominal Size Square Key |
Shaft (Arbor) & Key |
| E |
E |
F |
F |
| Hole Dia. |
(Square) |
Max. |
Min. |
Max. |
Min. |
| 1/⁄2 |
3⁄32 |
0.0932 |
0.0927 |
0.5468 |
0.5408 |
| 5/⁄8 |
1⁄8 |
0.1245 |
0.1240 |
0.6875 |
0.6815 |
| 3/⁄4 |
1⁄8 |
0.1245 |
0.1240 |
0.8125 |
0.8065 |
| 7⁄/8 |
1⁄8 |
0.1245 |
0.1240 |
0.9375 |
0.9315 |
| 1 |
1⁄4 |
0.2495 |
0.2490 |
1.0940 |
1.0880 |
| 1 1⁄/4 |
5⁄16 |
0.3120 |
0.3115 |
1.3750 |
1.3690 |
| 1 1⁄/2 |
3⁄8 |
0.3745 |
0.3740 |
1.6560 |
1.6500 |
| 1 3/⁄4 |
7⁄16 |
0.4370 |
0.4365 |
1.9380 |
1.9320 |
| 2 |
1⁄2 |
0.4995 |
0.4990 |
2.1880 |
2.1820 |
| 2 1⁄/2 |
5⁄8 |
0.6245 |
0.6240 |
2.7180 |
2.7120 |
| 3 |
3⁄4 |
0.7495 |
0.7490 |
3.2500 |
3.2440 |
| 3 1/⁄2 |
7⁄8 |
0.8745 |
0.8740 |
3.8750 |
3.8690 |
| 4 |
1 |
0.9995 |
0.9990 |
4.3750 |
4.3690 |
| 4 1/⁄2 |
11⁄8 |
1.1245 |
1.1240 |
4.9380 |
4.9320 |
| 5 |
11⁄4 |
1.2495 |
1.2490 |
5.5000 |
5.4940 |
All dimensions given in inches.
