Calculating best feed rate for CNC routers
Definition of terms
Feedrate is defined as the velocity at which the cutter is fed. Put simply, it is the distance the tool
travels during a single spindle revolution and is represented as distance per revolution.It is expressed
in units of distance per revolution for turning and boring (mm/min)
The chip load is the thickness of the material that the tool removes per tooth per revolution,
measured in inches or millimetres.
The spindle speed is the rotational speed of the spindle, measured in RPM
Feed rate is calculated using the following equation:
Feed = N x T x Z
Where
N = number of cutting edges (flutes)
T= chip load (chip 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. (mm per tooth)
Z= RPM, the speed at which the cutter revolves in the spindle. (Revolutions per minute)
