What is a cutting tool's 'rake angle'?

The rake angle of a cutting tool is defined as the angle of the cutting edge in relation to the workpiece surface. This angle is significant because it plays a crucial role in determining how efficiently the tool can engage the material being cut. A positive rake angle means that the cutting edge is sloped away from the workpiece, which can reduce the cutting force and improve chip flow. This aspect can enhance the tool's performance, leading to better surface finishes and prolonged tool life.

Understanding the rake angle is essential for optimizing cutting conditions, as it directly impacts the cutting action and the forces acting on the tool. The right rake angle can minimize friction and heat generation at the cutting interface, which is vital for both tool longevity and the quality of the machined part. Consequently, diverse applications might call for different rake angles, tailored to the specific materials being machined and the desired outcome.