Turning is the process of creating cylindrical forms. The workpiece is held in a chuck, or sometimes a collet, that rotates. A cutting tool is brought to the side of the workpiece and moves parallel to the workpiece axis to reduce or “turn down” the diameter. With careful setup, turning can also produce tapers or cones and cylindrical bores.
For generations turning was performed on manual machines. Then, in the 1960s and 70s, Computer Numerical Control, or CNC came along. With this, the motion of the lathe spindle and tool holder X and Z axes are managed by a computer program. Speed and movement are controlled to extreme precision, and most importantly, the movements are totally repeatable.
The beauty of CNC turning is that it’s capable of producing complex parts in the least possible time. This makes it as powerful for one-offs and prototype parts as for long runs. When used for quantity production, advanced control technology means the finish and geometry of the last part will be the same as the first part.
A limitation of turning is the surface finish that’s achievable. As a single-point cutting process, turning produces a finely grooved surface. Selecting a large radius cutting tool and reducing the feed rate minimizes this texture but it’s hard to achieve an Ra better than 25 µinch/0.63 µm. That’s why, for precise surface finishes, turning is usually followed by grinding.
Shafts, valve spools, collars, hubs, pulleys, and couplings are just a few examples of parts produced by turning. Some of these will subsequently need grinding, especially if they incorporate bearing journals or surfaces with precision fits like valve spools.
Turning (3 Lathes)
Max Turning Diameter: 14”
Distance Between Centers: 23”
Swing Over Diameter: 20”
Max bar capacity: 2”