Conventional milling and climb milling are two types of milling operations that define how the cutter engages with the workpiece. The main difference between them is how the workpiece feed direction is with respect to the cutting tool’s rotation.
In conventional milling, or up milling, the feed direction opposes the cutter’s rotation. This causes the cutting edge to initiate the cutting as rubbing and then slowly transition to pure shear. As a result of the cutting direction, the chip width starts from zero and is maximum when the cutter exits the workpiece. Generally, conventional milling is more stable in terms of vibration and dealing with machine backlash.
In climb milling or down milling, on the contrary, the feed direction aligns with the cutter’s rotation. The chip width starts at its maximum and gradually goes to zero, leading to a smooth cutting load trend. Climb milling is the preferred milling technique as it yields a better tool life, surface finish, and low cutting loads.
