G76): boring cycle, spindle shift – Rockwell Automation 8520-MUM 9/Series CNC Mill Operation and Programming Manual Documentation Set User Manual

Page 647

Advertising
background image

Milling Fixed Cycles

Chapter 26

26-15

5.

Tap-out: The spindle and linear motion reverse to the clockwise
direction and retract to the R point.

The tap-out speed is determined by F

*

S unless you programmed D

(tap-out rpm), in which case tap-out speed is F

*

D.

At the R point, spindle rotation has ramped to zero.

6.

With G98 active, the cutting tool then accelerates to the rapid feedrate
and retracts to the initial point level.

With G99 active, the cutting tool remains at R point; no movement
occurs.

In single-block mode, the control stops axis motion after phases 1, 2, 3,
and 6 of the cycle (Figure 27.M1).

Important: When it is active, S--Curve Acc/Dec (G47.1) will be applied to
the rapid feedrate portions of the solid--tapping cycle.

The format for the G76 cycle is as follows:

G76X__Y__Z__

I__J__K__

R__F__L__;

Q__

Where :

Is :

X,Y

specifies location of the hole.

Z

defines the hole bottom.

Q or I, J, K

defines the tool shift amount and direction.

R

defines the R point level.

F

defines the cutting feedrate.

L

defines the number of times the milling fixed cycle is repeated.

(See section 26.3 for a detailed description of these parameters.)

Important: The programmer or operator must start spindle rotation.

(G76): Boring Cycle,
Spindle Shift

Advertising