Rockwell Automation 8520-GUM 9/Series CNC Grinder Operation and Programming Manual Documentation Set - Manual (Page 479)

Angled-Wheel Grinding
Chapter 14
14-11
The W axis must be homed before any programmed motion can occur on
the X axis. If a rotary axis is used to determine the angle of the wheel axis,
that rotary axis must also be homed before positioning on the X axis can
occur.
Acceleration/Deceleration Considerations
While in the G16.4 two step angled wheel mode, there is a complete
deceleration of the axis to zero at the end of each step. When in
positioning mode (G00) or in exact stop mode (G61), the control will
perform an in-position check after each step before continuing execution.
Canceling G16.4 mode
The G16.4 mode is modal with other group 15 G codes. The following G
codes cancel the G16.4 mode:
G16.3 -- Normal Angled-Wheel Grinding Mode
G15 -- Angled-Wheel Transform Off
Programming a G15 cancels both angled-wheel grinding modes. The G15
command must be programmed in a non-motion block (no axis commands
allowed in the block). In the G15 mode the virtual X axis can not be
programmed. Any part program blocks that contain an X axis command
will generate an error when executed in G15 mode.
Programming a part contour (or any wheel path) relative to the part on an
angled-wheel grinder while not in one of the angled-wheel grinding modes
is difficult. Because of the angle of the grinding wheel, the part
programmer must consider that any W axis motion generates motion along
both the Z and X axes. In G15 mode W axis moves must be programmed
directly.
14.3.3
Angled-Wheel Transform Off
(G15)