Hybrid layered manufacturing: direct rapid metal tool-making process

The fabrication method for direct metallic tools presented here combines synergic gas metal arc welding and computer numerical control (CNC)machining processes in order to exploit the benefits of both while avoiding their limitations. A programmable logic controller (PLC)-based lowcost three-axis manipulator is fabricated with a stepper motor driver in open-loop control. The tool head will hold the welding torch and milling cutter. At any time, either milling or welding will take place; for that the welding gun can be moved up and down with a pneumatic operation. The welding parameters such as current, voltage and arc length are controlled externally. The framework also consists of a software program which uses the zeroth-order edge approximation uniform slicing strategy to calculate each slice thickness to be deposited with the required metal as successive layers from lower to topmost layer with the welding process. Further it generates the required CNC code for machining from the top to bottom layer direction of the deposited ametallic layers to attain the required contour profile shape with user specified accuracy. By attaining this cutting edge technology the manufacturers find metallic rapid prototyping to be the technique for the future.