Abstract: A coated hole cutter including an ink-based colored coating applied only to the external surface of the cylindrical blade body of the hole cutter, but not to the surfaces of a circumferentially-extending cutting edge or to the interior surface of the blade body. The ink-based color coating is an ultraviolet activated ink that cures when the coating is exposed to a specific ultraviolet light intensity and wavelength. At least the surfaces of the cutting edge and the internal surface of the blade body, which do not include the coating, have a steam tempered oxide finish that imparts a color that contrasts with the color imparted by the coating.

Abstract: A hole cutter having an extruded plate cap and methods and apparatuses for making such caps and hole cutters. The plate cap has planar opposing external and internal surfaces with an extruded hub extending axially inwardly from the internal surface. An aperture extends axially through the hub from the external surface. At least a portion of the aperture can be threaded for threaded engagement with a driving arbor. The hub is long enough so that the threaded portion contains at least two full threads. A blade body with a cutting edge is attached to the cap to form a hole cutter.

Abstract: A coated hole cutter including an ink-based colored coating applied only to the external surface of the cylindrical blade body of the hole cutter, but not to the surfaces of a circumferentially-extending cutting edge or to the interior surface of the blade body. The ink-based color coating is an ultraviolet activated ink that cures when the coating is exposed to a specific ultraviolet light intensity and wavelength. At least the surfaces of the cutting edge and the internal surface of the blade body, which do not include the coating, have a steam tempered oxide finish that imparts a color that contrasts with the color imparted by the coating.

Abstract: A hole cutter having an extruded plate cap and methods and apparatuses for making such caps and hole cutters. The plate cap has planar opposing external and internal surfaces with an extruded hub extending axially inwardly from the internal surface. An aperture extends axially through the hub from the external surface. At least a portion of the aperture can be threaded for threaded engagement with a driving arbor. The hub is long enough so that the threaded portion contains at least two full threads. A blade body with a cutting edge is attached to the cap to form a hole cutter.