Spotting Drill Sizes

Spotting or Centering Drills are designed for centering work, making a starting hole for a larger drill and for chamfering. The short flute and overall length of these type drills is very rigid to ensure precise spotting prior to drilling. Use as large a drill diameter as is reasonable for the best results.
| Size | Decimal Equiv. | Flute Length inch | Overall Length inch |
| 1/8 | .125 | 3/8 | 1-1/4 |
| 3/16 | .1875 | 1/2 | 1-3/8 |
| 1/4 | .250 | 5/8 | 1-1/2 |
| 5/16 | .3125 | 5/8 | 1-1/2 |
| 3/8 | .375 | 1 | 2 |
| 7/16 | .4375 | 1 | 2 |
| 1/2 | .500 | 1 | 2 |
| 9/16 | .5625 | 1 | 2 |
| 5/8 | .625 | 1-1/8 | 2-1/4 |
| 3/4 | .750 | 1-1/8 | 2-1/4 |
| 7/8 | .875 | 1-1/4 | 2-1/2 |
| 1 | 1.000 | 1-1/4 | 2-1/2 |
| 1-1/4 | 1.250 | 2 | 4 |
| 1-1/2 | 1.500 | 2-1/2 | 5 |
| 1-3/4 | 1.750 | 2-3/4 | 5-1/2 |
