Turning involves a fixed and non-rotating cutter, because in turning, the workpiece spins instead of the tool. Turning tools typically consist of a replaceable insert in a turning tool body.
The insert can be distinctive in a number of ways, including shape, material, coating and geometry. The shape can be round to maximize edge strength, diamond-shaped to allow a sharp point to cut fine features, square, or even octagonal to increase the number of separate edges that can be applied as one edge after another wears out. The material is typically carbide, though ceramic, cermet or diamond inserts can be applied to more demanding applications. A variety of protective coatings also help these insert materials cut faster and last longer. The geometry of the insert generally relates to its cutting angles, though the tool may also include a complex chipbreaker pattern that prevents long unbroken chips from becoming entangled in the cut.
The turning tool body generally does not feature quite so much engineering, but even here there are a range of choices for fine-tuning the process. Quick-change tools involve modular bodies that allow replacement tool bodies to be swapped in and out and locked in place quickly to minimize setup time. The turning tool body can also channel high-pressure coolant more effectively to the cutting edge of the tool.