Counter boring tool for metal machining - has cutting edges set at given angles to reduce consumption and extend life

摘要

The counter-boring tool has a shank (11) with four equally spaced radial blades (15-17). The angle of the cutting edges (18) on the end faces of these blades lies between 30 deg. and 35 deg. The helix angle of the outer edges (39, 40) of the blades lies between 40 deg. and 45 deg. w.r. t. the shank axis (12). The helix angle of the root (41) of the blades lies between 20 deg. and 25 deg. w.r.t. the shank axis. The front and rear edges of each blade run parallel to each other. The rear face of each blade lies approximately in a plane which is tangential to the shank surface. This design of cutter requires less operating power and has a much longer service life than conventional counter-boring tools.