For most material that you will be cutting on a CNC router you will typically set the RPM between 12000 and 24000, and adjust your feed rate to obtain the required results. The speeds and feeds chosen can be affected by the power of the spindle being used.

Calculation are as follows: Chip Load = Feed Rate (inches per minute) / (RPM x number of flutes). Example: Chip Load = 500 inches per minutes / (15,000 RPM x 2 flutes) Chip Load = . 017″. Chip loads are based on the material thickness of average size for the cutting edge length of the tool.

Feed Rate = N x cpt x RPM Where: > N - number of cutting edges (flutes) > cpt - chip load (chip load per tooth) is the amount of material, which should be removed by each tooth of the cutter as it rotates and advances into the work.