Turning is primarily used to generate which type of surface?

• A. Rectangular surfaces
• B. Cylindrical surfaces
• C. Spherical surfaces
• D. Irregular surfaces

Answer: (B)

Turning uses a rotating workpiece and a stationary cutting tool that feeds along the axis to shave away material, creating surfaces of revolution around the axis. The most common outcome is a cylindrical surface, where the diameter stays constant along the length. If you vary the tool path to a slight angle, you can also get a tapered cylindrical surface, but it’s still a cylinder family. Rectangular surfaces are typically produced by milling or planing, spherical surfaces come from other processes that shape curvature in multiple directions, and irregular surfaces require nonuniform or specialized tooling. So the surface turning primarily generates is cylindrical.