Abstract: A method is presented to make an investment casting pattern of a rotatable turbine wheel or a stationary turbine nozzle wheel having one continuous and regular series of blades extending around its periphery with a uniform pitch between blades and in which all such blades are bent in one circumferential direction and adjacent blades overlap each other in a circumferential direction so that the wheel pattern cannot be made in a simple two part mold separating at right angles to a parting line. The method comprises separately forming two wheel pattern portions of the same diameter as the finished turbine wheel pattern, each having a series of continuous and regular blades around its periphery with a uniform pitch between the blades which is exactly twice the pitch of the blades in the finished wheel pattern. In such a pattern wheel portion the adjacent blades do not overlap each other.