Milling Arc using G2 I & J CNC Program Example

CNC Program example code with drawing to show how an arc can be milled on a cnc milling machine.
G02 Circular interpolation Clockwise with I & J is used for arc machining.

G2 Circular Interpolation CW

G2 X... Y... I... J...
ParameterDescription
XCoordinates of the arc end point in x-axis.
YCoordinates of the arc end point in y-axis.
IDistance from arc start-point to arc-center-point in X-axis.
JDistance from arc start-point to arc-center-point in Y-axis .

Program Example

Milling Arc using G2 I & J

Milling Arc using G2 I & J

G0 X0 Y0                      (P1)
G1 X0 Y-1.493 F...            (P2) 
X1.939                        (P3)  
G2 X1.5 Y-2.5 I1.061 J-1.061  (P4)
G1 X0                         (P5)

G2 I & J Calculation Method

The image below shows how I & J values are calculated for Arc machining with  G2 circular interpolation.

G2 I & J Calculation

G2 I & J Calculation