A spinner for fiberizing glass has fiberizing holes formed in the spinner sidewall by a process utilizing an electron beam perforating process. A backing material used in the process is deposited on the walls of the fiberizing holes for increasing the corrosion resistance of the fiberizing holes. With regard to the formation of each fiberizing hole, an interaction of the backing material with an electron beam during the electron beam perforating process creates a gaseous backing material that expands through a hole created by the electron beam in the spinner sidewall to eject molten alloy material of the spinner sidewall made molten by the electron beam from the hole and deposit a thin substantially uniform coating layer of the backing material on the wall of the hole to increase the corrosion resistance of the fiberizing hole thus formed.