Drill Bit Speeds
DRILL BIT SPEEDS
Sizes are in inches and speeds are in RPM's
| Twist Drill Speed | Softwood | Hardword | Acrylic | Brass | Aluminium | Steel |
|---|---|---|---|---|---|---|
| Size (inches) | Speed (RPM) | |||||
| 1/4 - 3/16" | 3000 | 3000 | 2500 | 3000 | 3000 | 3000 |
| 1/4 - 3/8" | 3000 | 1500 | 2000 | 1200 | 2500 | 1000 |
| 7/16 - 5/8" | 1500 | 750 | 1500 | 750 | 1500 | 600 |
| 11/16 - 1" | 750 | 500 | * | 400 | 1000 | 350 |