In CNC milling, after selecting a tool, many people usually do not understand how much cutting speed and how many speeds to choose, but only through experiments. As long as there are no special problems, it is considered acceptable. Doing so is very dangerous. The most frequent problem is broken knife, or the material melts or becomes scorched.
Milling cutting speed refers to the instantaneous speed of the selected point on the tool relative to the corresponding point of the workpiece.
Vc=πDN/1000
Vc cutting speed, unit m/min
N Tool speed, unit r/min
D Milling cutter diameter in mm
Cutting speed is affected by factors such as tool material, workpiece material, machine tool part rigidity, and cutting fluid. Generally, the lower cutting speed is often used to process hard or ductile metals, which belongs to powerful cutting, and the purpose is to reduce tool wear and extend the service life of the tool. Higher cutting speed is often used to process soft materials, the purpose is to obtain better surface processing quality. When a small-diameter tool is used to perform micro-cutting on a brittle material workpiece or a precision component, a higher cutting speed can also be used. For example, using high-speed steel milling speed, aluminum is 91 ~ 244m/min, bronze is 20 ~ 40m/min.