Orbital cutting tool having cutting edges with axially varying circumferential spacing

A cutting tool for use in an orbital drilling machine may include a cutting-tool body having a longitudinal axis and a plurality of cutting edges supported on the cutting-tool body and distributed circumferentially around the cutting-tool body. Each cutting edge mayextend along the longitudinal axis in a respective helix. A circumferential spacing may be defined between each pair of circumferentially adjacent cutting edges for each position of the longitudinal axis along which the cutting edges extend. The circumferential spacing between at least first and second cutting edges of the plurality of cutting edges may be different at spaced-apart first and second positions along the longitudinal axis.