Tag Archives: COUNTERBORES

Counterbores with 4 flutes type N-N/T group 0-1-2 in HSS hardness 63 HRC, from Ø 7 to Ø 85. Helix angle 40°. You can fit them in all the Polledri mandrels of the same group. These counterbores are manufactured to solve all the problems of cylindrical head screw counterboring and spot-facing. With rotatory pilots or drills you […]

Counterbores with 3 flutes type H-H/T group 0-1-2 in hard metal quality ISO K 30 from Ø 10 to Ø 85. Helix angle 50°. You can fit them in all the Polledri mandrels of the same group. These counterbores are manufactured to solve all the problems of counterboring head screw and spot facing on cast […]