In lathe work, what defines the cutting action?

The cutting action in lathe work is primarily defined by the geometric shape of the cutting tool. The design of the cutting tool, including its angles, shape, and size, determines how it interacts with the material being machined. For example, the tool's rake angle, clearance angle, and cutting edge shape influence the efficiency of the cutting process, the quality of the surface finish, and the ability to effectively remove material.

The shape of the cutting tool also affects chip formation and flow, which are critical for maintaining optimal cutting conditions and tool life. Different shapes are suited for specific operations—turning, facing, chamfering, etc.—and choosing the correct tool geometry is essential for achieving the desired specifications and tolerances in the final product.

While factors like the speed of the lathe, type of workpiece material, and depth of cut certainly play important roles in machining processes, they are secondary to the influence exerted by the cutting tool's geometry on the actual cutting action. Understanding the interaction between the tool shape and the workpiece allows machinists to optimize their procedures for quality output.