Abstract: In a continuous screw conveyor or auger, the rotatable screw member comprises a helical radial blade (“flighting”) carried on a central driving shaft. The flighting is formed by providing a raw metal strip, generally of uniform thickness, performing optional compression and flaring of the metal strip, and rolling the metal strip between a pair of opposed, preferably offset, conical rolls. In contrast to prior art rolls, the present invention provides on at least one of those rolls a stepped conical rolling surface formed so as to exert a lesser and reducing rolling pressure on an outer portion of the helical blade being formed, thereby to produce a blade in which the outer portion tapers to a thickness which is preferably 125% of the thickness of the ingoing material to provide a greater wear resistant surface, a longer working life to the flighting and improved output performance.