MCS represents the machine’s reference frame, typically defined by the machine builder. It serves as the zero point for all machine movements and is essential for CNC programming. In STEP and DXF workflows, MCS is used to transform part coordinates (PCS) into machine coordinates, ensuring that tool paths align correctly with the physical machine axes.
Understanding MCS is crucial for post-processing and simulation because any mismatch between PCS and MCS can lead to collisions or incorrect machining. CAM systems often allow users to define work offsets relative to MCS, enabling flexible setups without altering the original part geometry.