Head Diameter | 1/4"(6mm) | 5/16"(8mm) | 3/8"(10mm) | 1/2"(12mm) |
Max RPM | 65,000 | 60,000 | 55,000 | 35,000 |
Steel | 35,000-45,000 | 30,000-40,000 | 22,500-35,000 | 20,500-30,000 |
Cast Iron | 22,500-45,000 | 20,000-40,000 | 15,000-35,000 | 11,000-30,000 |
Brass,Copper,Bronze | 22,500-45,000 | 20,000-40,000 | 15,000-35,000 | 11,000-30,000 |