In the field of precision CNC machining, multi-axis CNC machining has become a core technology in aerospace, medical device, and automotive parts manufacturing. What is multi-axis CNC machining? It refers to the process where a machine tool controls multiple axes—either simultaneously or in a positioning manner (X, Y, Z linear axes plus A, B, C rotary axes)—to achieve complex surface machining. It is mainly divided into two modes: 3+2-axis and full 5-axis simultaneous machining.
3+2-axis machining (also known as positional 5-axis CNC) uses three linear axes plus two rotary axes. The rotary axes are only responsible for positioning and angle adjustment of the workpiece. Once locked, the actual cutting is performed by the three linear axes. Its significant advantages include simple programming, lower machine cost, and high stability, making it ideal for mass production of moderately complex parts such as mold cavities, electronic housings, and automotive brackets. The main drawback is that it cannot continuously machine deep cavities or multi-angle curved surfaces, requiring multiple repositioning, which may result in visible tool marks on the surface.
Full 5-axis simultaneous machining enables all five axes to move and interpolate synchronously, allowing the completion of complex free-form surfaces in a single setup. Its advantages include significantly reduced clamping times (efficiency improved by over 30%), superior surface finish (Ra 0.8μm or better), and high machining accuracy (±0.005mm). It is particularly suitable for high-difficulty parts such as turbine blades, medical implants, and artistic sculptures. However, the disadvantages are higher equipment investment (typically 1.5–2 times that of 3+2-axis machines), more demanding programming software, and a higher skill threshold for operators.
How to choose? For parts with low geometric complexity and large production volumes, 3+2-axis machining is preferred to control costs. For parts requiring high-precision continuous curved surfaces or small-batch custom production, full 5-axis machining is recommended.