NCprogramma

NC-programma, or NC program, is a set of instructions that directs a numerically controlled machine tool to manufacture a part. It specifies the movements of machine axes, spindle speed, tool changes, coolant, and other auxiliary actions needed to perform operations such as milling, turning, drilling, or routing.

Most NC programs are written in G-code, sometimes with M-code commands for auxiliary functions. Each line (block) typically represents a single action, such as a move or a change of state. Common elements include coordinates (X, Y, Z), feed rate (F), spindle speed (S), and tool selection (T). Programs also use absolute or incremental positioning (G90/G91), work coordinate systems (G54–G59), and tool length or radius compensation (G43, G41, G42). Canned cycles and subroutines may appear in more complex programs.

Creation and workflow: NC programs can be written manually by machinists or, more often, generated by computer-aided manufacturing (CAM) software. A post-processor translates a CAM toolpath into a machine-specific dialect. Files are typically saved with extensions such as .nc or .gcode and are loaded into the CNC controller where they are executed or simulated beforehand to verify movements and avoid collisions.

Variants and standards: Different controllers from vendors such as FANUC, Siemens, Haas, and Mazak use dialects of G-code, with proprietary additions and safe-guards. Many programs adhere to international guidelines such as ISO 6983, which defines the representation of numerical control data, while vendors provide specific menus and macros for enhanced functionality.

Overall, an NC-programma serves as the bridge between CAD/CAM design and physical fabrication, translating digital models into precise, repeatable machine actions.