The peripheral cutting edge of an end mill refers to the portion of the cutting edge located along the outer diameter of the tool, where the flutes meet the cylindrical surface. This edge is responsible for generating the sidewall of a cut when performing contouring, profiling, or slotting operations. It is defined by the tool’s helix angle, rake angle, and relief angle, all of which influence cutting forces, chip evacuation, and surface finish.
A well-designed peripheral cutting edge ensures efficient material removal while minimizing deflection and chatter. The helix angle plays a key role in controlling the cutting forces and chip flow, with higher angles producing smoother cuts at the expense of increased axial force. The sharpness and geometry of the cutting edge affect how aggressively the tool engages with the material, impacting tool wear and surface finish.