CNC Drilling

Process Definition & Working Principle

CNC drilling is a fundamental subtractive manufacturing process that creates cylindrical holes in solid workpieces or enlarges existing holes using a rotating cutting tool. The process is numerically controlled to ensure high positioning accuracy, precise depth control, and repeatable performance.

The mechanics of drilling rely on the simultaneous execution of two primary motions:

1. Primary Cutting Motion (Rotational): The tool (or spindle) rotates at a specific angular velocity, which determines the peripheral cutting speed ($v_c$) at the outer diameter of the drill.
2. Feed Motion (Linear Translational): The drill advances axially into the workpiece at a linear feed rate ($v_f$).

Within the cutting zone, three distinct deformation regions drive the chip formation process: