CNC turning is a machining process in which a pointed cutting tool is moved linearly on the surface of the rotating workpiece to create the desired end shape. The lathe secures and rotates the piece while the cutter moves parallel to the axis of rotation along a prescribed straight or helix toolpath to remove the material. When the tool is moved along the external surfaces, the process is referred to as turning the removal of material from internal surfaces is known as “boring.”
Traditionally, Swiss screw machining involved continuous operator attention, but with the advent of computers today, the only human intervention required in CNC (Computer Numeric Control) turning machines is to program the system. The required design is loaded into the software, which then calculates the exact physical movements of the cutting tool along the x, y and z axes. Automation of the system allows for far more complex shapes than were possible by hand, in addition to tighter tolerances and greater precision.
This type of precision machining center can carry out various types of operations in addition to mere material removal — tapering, grooving, knurling, and threading, for instance. Sophisticated centers with live tooling options allow for additional operations such as milling, drilling holes, reaming and creating slots. Such machines are known as multitasking machines. In addition, parts with multiple axes, such as automotive parts, can also be made with CNC turning.
CNC turning provides an economical means of producing precision parts that are basically cylindrical in shape, such as shafts, hubs, bushings and other parts. These machines can also be used to cut metal objects with circular cross-sections. Thus, they are best suited for high production volumes with maximum precision and accuracy.