Computer Numeric Control (CNC) has become an integral part of the modern factory. But without a background in engineering and programming, you may be a little confused – what is CNC, how does it work and what is CNC programming?
In this guide, we’ll break down CNC, detailing some of its history and uses.
CNC technology began in the 1950s. Mechanical punched cards were used to tell machines what to do. By entering the cards, operators could ‘program’ a machine to perform a series of actions. But while CNC began in the 1950s, it didn’t really take off until the widespread adoption of computers and robotics. Computers allowed an operator to enter and store specific programs directly into a CNC machine, streamlining even program entry.
All of this tells us when CNC started and the benefits it offers, but what about the technology itself? How does a CNC programme run – and what is the input process?
CNC programming is based on a special form of code, descended from the punched cards of the earliest CNCs. Most CNC programming lines are short coordinate and command strings.
The letter would be followed by a number – G76, for example – which indicated the starting position for the programme. The G-code told the CNC machine where to move the tool to prepare for the rest of the programme. Over time, the CNC programming language became known simply as g-code.
G-code is the most basic form of CNC programming; it’s the programming language used by the other methods. But it can also be the most difficult to learn; the other two methods are ways of getting around actually programming directly in G-code.
Computer-Assisted Manufacturing (CAM) software is a variant of Computer-Assisted Design (CAD) software. Both use a computer program to design, lay out and program instructions for a CNC machine. It’s the program itself that translates the design into instructions for the CNC machine.
Conversational software uses an interface to translate normal commands. It’s not as comprehensive or versatile as g-code, but it makes the interface much simpler.
