INTERCHANGEABLES COUNTERBORES TYPE 1N

COUNTERBORES WITH 4 FLUTES in HSS HRC 63 from Ø 10 to Ø 40.

Counterbores with 4 flutes type N-N/T group 1 in HSS hardness 63 HRC, from Ø 10 to Ø 40. Helix angle 40°. You can fit them in all the Polledri holders 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 can execute simultaneous operations. We advise them for materials with short and normal chip.