Computers and machine tools have no intelligence. They cannot think, they cannot evaluate a situation in a rational way. Only people with certain skills and knowledge can do that. In the field of numerical control, the skills are usually in the hands of two key people – one doing the programming, the other doing the actual setup and machining. Their respective numbers and duties typically depend on company preferences, its size, as well as the product manufactured there. However, each position is quite distinct, although many companies combine the two functions into a one, often called a CNC Programmer/Operator.
CNC programmer is usually a person who has the most responsibility in the CNC machine shop. This person is often responsible for the success of numerical control technology in whole the plant. Equally, this person is also held responsible for problems related to CNC and related operations. Although duties may vary, the programmer is also responsible for a variety of tasks relating to the effective usage of one or more CNC machines. In fact, this person is often accountable for the production and quality parts from all CNC operations.
Many CNC programmers are experienced machinists who have had a practical, hands-on experience as machine tool operators. They know how to read technical drawings and they can comprehend engineering intent behind the design. This practical experience is the main foundation for the ability to ‘machine’ a part in an off-machine environment. A good CNC programmer must be able to visualize all tool motions and recognize all restricting factors that may be involved. The programmer must be able to collect, analyze, process and logically integrate all collected data into a single, cohesive and safe part program. In simple terms, the CNC programmer must be able to decide upon the best manufacturing methodology in all respects.
In addition to machining skills, the CNC programmer has to have a good understanding of mathematical principles, mainly application of equations, solution of arcs and angles. Equally important is the knowledge of trigonometry. Even with computerized programming, the knowledge of manual programming methods is absolutely essential to deep and thorough understanding of computer output and to assure control over such output.
The last important quality of a truly professional CNC programmer is his or her ability to listen to other people – the engineers, CNC operators, managers. Good listening skills are the first prerequisites to become flexible. Any professional CNC programmer must be flexible in order to offer high quality in programming.
CNC Machine Operator
The CNC machine tool operator is a complementary position to that of CNC programmer. The programmer and the operator may exist in a single person, as is common in many smaller shops. Although the majority of duties performed by a conventional machine operator has been transferred to CNC programmer, CNC operator also has many unique responsibilities. In typical cases, the operator is responsible for tool and machine setup, for changing of completed parts, often even for some in-process inspection. Many companies expect quality control at the machine and the operator of any machine tool, manual or computerized, is also responsible for the quality of work done on that machine. One of the most important responsibilities of CNC machine operator is to report findings about each program to the programmer. Even with the best knowledge, skills, attitudes and good intentions, the ‘final’program can always be improved. CNC operator, being the one who is the closest to actual machining, knows precisely what extent such improvements can be.