An end mill is provided having an axis of rotation, a shank section and a fluted section, each extending along the axis of rotation, and a plurality of helical teeth. The fluted section has a first end attached to the shank section and a second end. The plurality of helical teeth is disposed within the fluted section. Each helical tooth has a cutting edge, a relief surface, a cutting surface, and an edge preparation surface. The edge preparation surface is contiguous with the cutting edge of the respective tooth.