CNC Fanuc G73 Pattern Repeating Cycle

In cnc machine workshop you might have machined different kind of components but before machining a component you have to select the ‘raw piece of material’ from which you will produce the finished component.

The raw material selection is purely dependent over the finished component shape, if you are going to produce a component which will have an internal bore and threads then surely you will select some kind of raw component which has a pipe like shape or something resembling.

Most of the time we have to machine some kind of pre-shaped raw-components. Those pre-shaped raw-component might be some kind of forging or casting.

If you are given a pre-shaped raw-component then using a normal Longitudinal Cutting Cycle (Fanuc G71), or Traversal Cutting Cycle (Fanuc G72) is just a waste of time and energy.

The best option to machine a pre-shaped raw-component is to use a Pattern Repeating Cycle (Fanuc G73).

Fanuc G73 pattern repeating cycle doesn’t make straight cuts like longitudinal cutting cycle (Fanuc G71) or traversal cutting cycle (Fanuc G72) but a pattern repeating cycle Repeats the whole profile or pattern of the contour.

Explanation of Fanuc G73 Pattern Repeating Cycle

N10 G73 U W R
N20 G73 P Q U W

G73 First CNC Program Block

U : Distance and direction of relief in x-axis (radius value). This is the amount of material which will be cut in x-axis.

W : Distance and direction of relief in z-axis. This is the amount of material which will be cut in z-axis.

R : Number of divisions. The number the contour will be repeated.

G73 Second CNC Program Block.

P : The contour start block number.

Q : The contour end block number.

U : Finishing allowance in x-axis.

W : Finishing allowance in z-axis.