Abstract: An injection molding apparatus capable of producing disposable wax patterns or the like and which apparatus includes a logic control and a servo-control especially designed to provide a substantially automatic molding process and to continuously monitor and to dynamically control certain variable parameters which are encountered during the molding process, as for example, in the present embodiment of apparatus, the control of the dynamics of fluid (wax) flow and pressure for providing substantially an automatic molding process.The servo-control is a "closed loop" servo type of control which, in the present embodiment of apparatus, continuously provides signals which relate to the fluid (wax) flow, i.e.

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.