Rockwell Automation 8520-GUM 9/Series CNC Grinder Operation and Programming Manual Documentation Set - Manual (Page 560)

Surface Grinding Fixed Cycles
Chapter 16
16-10
K - cross pick amount at primary reversal.
The value entered here is an incremental value used to indicate the distance
that the crossover axis moves as soon as the reciprocating axis begins
decelerating from its primary reciprocating move.
This parameter is “program modal,” meaning that it needs to be
programmed only once in a part program. Any subsequent surface
grinding blocks (G82 -- G86) use a previously programmed value if a new
value is not programmed.
Important: In grinding fixed cycle blocks where changes are made from
absolute to incremental or incremental to absolute modes within the block,
the integrands I, J and K are always in the last mode programmed in the
block, regardless of their position in the block.
R - cross pick amount at secondary reversal.
The value entered here is an incremental value used to indicate the distance
that the crossover axis moves as soon as the reciprocating axis begins
decelerating from its secondary reciprocating move. If no value is entered
for this, then the K value is used.
This parameter is not “program modal.” Any subsequent surface grinding
blocks (G82 -- G86) use the K value if an R value is not programmed.
Y - plunge depth.
If in incremental mode (G91 active) then the value entered here is a signed
incremental value used to indicate the distance from the start point to the
end of the plunge motion. If in absolute mode (G90 active) then the value
entered here is the Z coordinate of the end point of the plunge move.
This parameter is “program modal,” meaning that it needs to be
programmed only once in a part program. Any subsequent surface
grinding blocks (G82 -- G86) use a previously programmed value if a new
value is not programmed.