Square End Mills
In milling jobs, square end mills with a square nose rotate against a piece of stock to form a flat-bottomed groove with 90° inside corners. Counterboring, side and face milling, and milling square shoulders are all done with square-nose end mills. To avoid damage to the end mill or the workpiece, flutes on each of the end mills' cutting heads transport chips away from the workpiece. CNC and manual milling machines both employ square end mills.