CNC turning involves the use of CNC lathes or multi axis CNC turning centers. Manufacturers use CNC lathes to turn materials with cylindrical and concentric features on parts. The power lathe combines the end mill and drill bit to generate off-axis features without the need for platform replacement. By using professional CNC lathes (commonly referred to as Swiss machine tools) to combine multiple tools and spindles within the machine, small parts with complex features can be quickly produced.
A typical lathe rotates parts on the central axis to remove features by engaging rigid cutting tools. The other functions performed by the lathe include creating internal and external threads, creating flange features, O-ring grooves, and embossing textures.
CNC lathes and CNC milling machines have different shaft configurations. CNC lathes are usually 3-axis or 4-axis machines with a single spindle. 3-axis CNC machining is the process of machining materials on the X, Y, and Z axes, removing shavings along these three directions, while 4-axis cutting tools combine the concentric features of the lathe and the outward tilting motion of the milling machine. A lathe is an ideal choice for creating circular parts, with more intensive operations on irregular shapes and sharp edges, while a milling machine is the opposite.
More modern CNC technology supports up to 5 axes. These tools add tilt and rotation functions to the traditional X, Y, and Z axes, allowing for precise cutting of more detailed parts. 5-axis machining is also more efficient, allowing for the creation of more part features in one operation. Milling machines have multiple configurations, typically using 3-axis, 4-axis, and 5-axis.
CNC stands for computer numerical control, where operators use G code (a programming language that provides machine motion instructions) to control CNC milling machines and lathes. Modern programming instructions are created through computer-aided manufacturing (CAM) software. This code indicates that the machine moves the cutting head to a fixed position and can also control its speed and supply, including rotation, cutting depth, and workpiece movement. The complexity of G code depends on the number of axes of the machine and the toolset it uses.
