A permanent magnet machine includes a machine housing having an inner surface that extends between a first housing end and a second housing end along a central longitudinal axis. The permanent magnet machine also includes a stator disposed within the machine housing, the stator having a stator core having an exterior surface extending between a first face and a second face along the central longitudinal axis, wherein the exterior surface defines a discontinuous region that is arranged to minimize points of contact between the inner surface and the exterior surface. The discontinuous region is at least partially defined by at least one of a first perturbation and a second perturbation that is circumferentially spaced apart from the first perturbation.