Generalized groove-type chip breaker effects on drilling for different drill diameters and flute shapes

This paper proposes a generalized formulation to place chip-breaker grooves on drills of varying diameters. To verify the effectiveness of this generalization the groove is placed on the drill rake face of 6.35 and 3.18 mm diameter drills of standard and parabolic flute shapes using a fabrication process utilizing electro-discharge machining (EDM). The results indicate that chip size is reduced. The robustness of the placement of the groove is assessed with experiments validating effective distance from the cutting lip and groove depth thereby facilitating drill regrinding. Experiments are also conducted to study chip clogging when the chip-breaker groove is employed on small drill diameters.