A professional who plans numerical control program to control contour-path machining of metal parts on automatic machine tools. Responsibilities include:

• Analyzes drawings, sketches, and design data of part to determine dimension and configuration of cuts, selection of cutting tools, and machine speeds and feed rates, according to knowledge of machine shop processes, part specifications, and machine capabilities.
• Determines reference points and direction of machine cutting paths.
• Computes angular and linear dimensions, radii, and curvatures, and outlines sequence of operations required to machine part.
• Prepares geometric layout on graph paper or using computer-assisted drafting software to show location of reference points and direction of cutting paths, using drafting instruments or computer.
• Writes instruction sheets and cutter lists to guide setup and operation of machine.
• Writes program of machine instructions in symbolic language to encode numerical control tape or direct numerical control data base to regulate movement of machine along cutting path.
• Compares encoded tape or computer printout with original program sheet to assure accuracy of machine instructions.
• Revises program to eliminate instruction errors or omissions.
• Observes operation of machine on trial run to prove taped or programmed instructions.