Fanuc G72.1 Rotational Copy (Figure Copy Function CNC Mill)

Fanuc G72.1 Rotational Copy
Using G72.1 Rotational Copy G-code a figure specified by a subprogram can be repeatedly produced with Rotational movement.

Programming

G72.1 P... L... X... Y... R...

Parameters

ParameterDescription
PSubprogram number
LNumber of times the operation is repeated
XCenter of rotation on the X axis
YCenter of rotation on Y axis
RAngular displacement (a positive value indicates a counter clockwise angular displacement. Specify an incremental value.)

G-Code Data

Modal/Non-ModalG-Code Group
Non-Modal00

Programming Notes

Notes

  1. In the G72.1 block, addresses other than P, L, X, Y and R are ignored.
  2. P, X, Y and R must always be specified.
  3. If L is not specified, the figure is copied once.
  4. The coordinate of the center of rotation is handled as an absolute value even if it is specified in the incremental mode.
  5. Specify an increment in the angular displacement at address R. The angular displacement (degree) for the Nth figure is calculated as follows: Rx(N-1).

First block of the subprogram

Always specify a move command in the first block of a subprogram that performs a rotational copy. If the first block contains only the program number such as O00001234; and does not have a move command, movement may stop at the start point of the figure made by the n-th (n = 1,2, 3, …) copying.
Example of an incorrect program

O00001234 ;
G00 G90 X100.0 Y200.0 ;
;
;
M99 ;

Example of a correct program

O00001000 G00 G90 X100.0 Y200.0 ;
;
;
M99 ;

Limitation

Specifying two or more commands to copy a figure
G72.1 cannot be specified more than once in a subprogram for making a rotational copy (If this is attempted, alarm PS0900 will occur).
In a subprogram that specifies rotational copy, however, linear copy (G72.2) can be specified. Similarly, in a subprogram that specifies linear copy, rotational copy can be specified.

Commands that must not be specified
Within a program that performs a rotational copy, the following must not be specified:
Command for changing the selected plane (G17 to G19)
Command for specifying polar coordinates (G16)
Reference position return command(G28)
Axis switching
Coordinate system rotation (G68)
scaling (G51)
programmable mirror image (G51.1)
The command for rotational copying can be specified after a command for coordinate system rotation, scaling, or programmable mirror image is executed.

Single block
Single-block stops are not performed in a block with G721.1 or G72.2.

 

G72.1 Programming Example

Fanuc G72.1 Rotational Copy Example Program

Main program

O1000 ;
N10 G90 G00 X80. Y100. ;              (P1)
N20 Y50. ;                            (P2)
N30 G01 G17 G42 X43.301 Y25. D01 F100 ;(P3)
N40 G72.1 P1100 L3 X0 Y0 R120. ;
N50 G90 G40 G01 X80. Y50. ;           (P2)
N60 G00 X80. Y100. ;                  (P1)
N70 M30 ;

Sub program

O1100 G91 G03 X-18.301 Y18.301 R50. ; (P4)
N100 G01 X-5. Y50. ;                  (P5)
N200 G03 X-40. I-20. ;                (P6)
N300 G01 X-5. Y-50. ;                 (P7)
N400 G03 X-18.301 Y-18.301 R50. ;     (P8)
N500 M99 ;