cnc basic key terms
In the word address programming system, a group of program words that appear on the same line and are to be executed at the same time.
Block
CNC programming codes used to turn on and off miscellaneous functions.
M-codes
Machine codes that remain active until cancelled or overridden.
Modal
A device used in some CNC machines to automatically load, unload, and store tools.
Automatic tool changer (ATC)
CNC programming codes that prepare a machine to engage in a particular mode for machining; for instance, a G1 code tells the machine to feed in a straight line, or linear motion.
G-codes
Commanded by the G-codes G2 or G3, a type of motion that causes the cutter’s path to travel in an arc so that CNC machines can cut full or partial circles.
Circular interpolation
A referencing method used with coordinate systems in which the coordinates of all positions are referenced from the origin (X0, Y0, Z0).
Absolute positioning system
The semicolon character at the end of a block of CNC code that instructs the MCU to move on to the next block.
End of block
Designated by the G-code G0, a type of CNC machine motion used to quickly position tools near the workpiece before beginning a machining operation.
Rapid traverse
A special type of MCU function developed to simplify the machine programming process in which the operator selects the intended type of machining operation from an on-screen menu and the machine prompts the programmer with a series of questions.
Conversational programming
A computerized numerical control (CNC) mill equipped with an automatic tool changer.
Machining center
A computerized numerical control (CNC) lathe equipped with an automatic tool changer.
Turning center
Two- or three-dimensional systems that use X and Y or X, Y, and Z values for location.
Rectangular or Cartesian coordinate system
A referencing method used with coordinate systems which specifies a distance from the current position to the next position instead of a location related to the initial origin.
Incremental positioning system
A style of programming in which instructions are written in a code or format that can be understood and executed by a CNC machine tool.
Word address