High feed mills (also called high feed cutters or high feed face mills) are specialized milling tools designed to remove material at extremely high feed rates while maintaining low axial depths of cut. What sets them apart is the unique combination of shallow cutting depths and aggressive feed per tooth, which makes them ideal for roughing operations, especially in hard or difficult-to-machine materials.
The key feature of a high feed mill is the insert geometry. The cutting edges are positioned at a very shallow lead angle—typically around 10° or less. This geometry directs much of the cutting force axially into the spindle rather than radially into the cutter, reducing vibration and allowing for higher feed rates without compromising tool life. The inserts often have a large radius or a positive rake face to encourage smooth chip evacuation and maintain edge strength.
Despite taking relatively thin chips (due to the small depth of cut), the tool compensates by feeding rapidly across the surface, which results in high material removal rates. High feed milling is often used in mold and die work, aerospace components, and anywhere cycle time needs to be minimized while cutting tough alloys. Machine rigidity and a stable setup are essential, since these tools place significant loads along the spindle axis and rely on precise control to avoid chatter or uneven tool wear.