Modeling the mechanics and dynamics of arbitrary edge drills

• New method for modeling the cutting forces and vibration stability of drills with arbitrary edge geometry is presented.
• Cutting force coefficients are identified from non-symmetric drilling operations.
• Process damping coefficient is identified from orthogonal turning experiments and is applied for modeling process damping in drilling.
• The accuracy of presented method is verified by drilling experiments.

This paper presents a new approach for modelling the cutting forces and chatter stability limits in drills with arbitrary lip geometry. The oblique cutting geometry at each point on the drill lip is modelled using parametric curve equations. The cutting force and process damping coefficients at different parts of the drill lip are identified empirically; the cutting force coefficients are identified from non-symmetric drilling tests, and the process damping coefficients are identified from chatter-free orthogonal turning tests. The presented approach provides a practical method for modelling the cutting forces and vibration stability without needing the detailed geometry of drill lips. The accuracy of presented model in predicting lateral and torsional-axial chatter stability limits is verified by conducting drilling tests using drills with various edge geometries.