A gear cutting tool for producing bevel and hypoid gears comprising: a cutter head rotatable about a cutter axis and comprising a plurality of blade slot groups with each of said groups having at least two blade positioning slots, at least one blade slot group including a first cutting blade positioned in one of the blade positioning slots and a second cutting blade positioned in the other of the blade positioning slots, characterised by said first and second cutting blades (40, 41) each having a cutting end comprising a first cutting edge and a second cutting edge with the cutting ends of the first and second cutting blades being the same, said first and second cutting blades (41, 40) being operable to cut a tooth slot in a gear workpiece, said tooth slot defining a space between a convex tooth surface of one gear tooth and an opposite concave tooth surface of an immediately adjacent gear tooth on said workpiece, wherein said first and second cutting blades (41, 40) are positioned with respect to one another in said blade slot group either in a first orientation with one of said first and second cutting blades (41, 40) being operable to cut one of said convex tooth surface or said concave tooth surface of said tooth slot with one of said first cutting edge or said second cutting edge, and the other of said first and second cutting blades (41, 40) being operable to cut the other of said convex tooth surface or said concave tooth surface of said tooth slot with the other of said first cutting edge or said second cutting edge, or in a second orientation being opposite to said first orientation, wherein in said second orientation, said one of said first and second cutting blades (41, 40) is operable to cut the opposite tooth surface of said first orientation with the opposite cutting edge of said first orientation, and wherein said other of said first and second cutting blades (41, 40) is operable to cut the opposite tooth surface of said first orientation with the opposite cutting edge of said first orientation, wherein a tooth slot cut by said second orientation is the same as the tooth slot cut by said first orientation. a cutter head rotatable about a cutter axis and comprising a plurality of blade slot groups with each of said groups having at least two blade positioning slots, at least one blade slot group including a first cutting blade positioned in one of the blade positioning slots and a second cutting blade positioned in the other of the blade positioning slots, characterised by said first and second cutting blades (40, 41) each having a cutting end comprising a first cutting edge and a second cutting edge with the cutting ends of the first and second cutting blades being the same, said first and second cutting blades (41, 40) being operable to cut a tooth slot in a gear workpiece, said tooth slot defining a space between a convex tooth surface of one gear tooth and an opposite concave tooth surface of an immediately adjacent gear tooth on said workpiece, wherein said first and second cutting blades (41, 40) are positioned with respect to one another in said blade slot group either in a first orientation with one of said first and second cutting blades (41, 40) being operable to cut one of said convex tooth surface or said concave tooth surface of said tooth slot with one of said first cutting edge or said second cutting edge, and the other of said first and second cutting blades (41, 40) being operable to cut the other of said convex tooth surface or said concave tooth surface of said tooth slot with the other of said first cutting edge or said second cutting edge, or in a second orientation being opposite to said first orientation, wherein in said second orientation, said one of said first and second cutting blades (41, 40) is operable to cut the opposite tooth surface of said first orientation with the opposite cutting edge of said first orientation, and wherein said other of said first and second cutting blades (41, 40) is operable to cut the opposite tooth surface of said first orientation with the opposite cutting edge of said first orientation, wherein a tooth slot cut by said second orientation is the same as the tooth slot cut by said first orientation.