3-axis milling machines are limited in angle variation and can't achieve the complex undercuts or intricate angles possible with 5- or 6-axis machines, which limits their effectiveness in carving more complex stone designs.

In contrast to conventional 3-axis CNC machines that operate linearly along the X, Y, and Z axes, the 5-axis CNC machine introduces two additional rotational axes, typically labeled as A and B. This heightened flexibility proves especially advantageous in industries where precision and complexity play pivotal roles.

A 2.5 axis machine really has three moving axes, but only two axes can move together (most machines sold today are full three axis machines). For machining centers, a three axis machine will have three linear axes. A four or five axis machine will have three linear axes as well as one or two rotary axes.