Hurco winmax, Programming Manual

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WinMax Lathe NC Programming
704-0115-307
Basic NC G Codes
2-23
G74 - Left Hand Tapping
G74 executes the same as G84 Right Hand Tapping except the spindle directions are
reversed.
Default—No
Modal—No
M74 is required for the optional Rigid Tapping.
Cancels—None
The tool motion for this cycle is described below. The feedrate and spindle override
controls are forced to 100% are disabled while this cycle is active.
The drawing below shows left-hand tapping tool motion:
1. Tool rapids to R plane.
2. Tool feeds to the programmed depth.
3. Spindle reverses direction (CCW).
4. If G94 is active, the axis will dwell for P seconds; if G95 is active, the axis will
dwell for P revolutions.
5. Tool feeds to R plane.
6. Spindle reverses direction (CW).
Figure 2–10. G74 Left Hand Tapping
To stop tool motion when the tap is in the bore, either press the
Emergency Stop button or use Retract.
The control will not respond to a motion-stop command until the tool
returns to the reference plane.