System information

SECTION FOUR - PREPARATORY FUNCTIONS (G CODES)

Left hand soft tapping cycle (G74)

G74 G98/G99 Z___ R___ B___ P___ F___

The G74 command specifies the left hand soft tapping cycle. At each axis position, this cycle

will do the following.

1. Rapid to point R

2. Feeds to point Z

3. Dwells before reversing (specified by the B code)

4. Reverses spindle (CW)

5. Dwells after reversing (specified by the P code)

6. Feeds to point R

7. Reverses spindle (CCW)

8. Rapids to initial point, if specified by the G98 code

Note: During tapping, the feedrate override and spindle override switches are ignored. When in

the block mode, the cycle does not stop until the tap is completed. When feedhold or halt

is applied, the tap will stop when it is out of the hole.

Calculating Feeds and Speeds for Tapping

= LEAD

PITCH

RPM X LEAD = FEEDRATE

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