Fanuc G76 Fine Boring Cycle – CNC Mill

Fanuc G76 Fine Boring Cycle

Fanuc G76 Fine Boring Cycle bores a hole precisely.  When the bottom of the hole has been reached, the spindle stops, and the tool is moved away from the machined surface of the workpiece and retracted.
Fanuc G76 Fine Boring Cycle is used for enlarging borings with boring and facing heads, Fanuc G76 Fine Boring Cycle is also called Fanuc G76 Fine Drilling Cycle.

Programming

G76 X Y Z R Q P F K

Parameters

ParameterDescription
X YHole position data
ZAbsolute hole depth position
RPosition of the R plane
QShift amount at the bottom of a hole
PDwell time at the bottom of a hole
FCutting feedrate
KNumber of repeats (if required)

Fanuc G76 Fine Boring Cycle

Operation

When the bottom of the hole has been reached, the spindle is stopped at the fixed rotation position, and the tool is moved in the direction opposite to the tool tip and retracted.  This ensures that the machined surface is not damaged and enables precise and efficient boring to be performed.

Be sure to specify a positive value in Q.  If Q is specified with a negative value, the sign is ignored.  Set the direction of shift in bits 4 and 5 of parameter 5101.

Bit 5 Bit 4 = Shift
   00         X+
   01         X-
   10         Y+
   11         Y-

Example Program

M3 S500
G90 G99 G76 X300. Y–250. Z–150. R–120. Q5. P1000 F120.
Y–550.
Y–750.
X1000.
Y–550.
G98 Y–750.
G80 G28 G91 X0 Y0 Z0
M5