Rockwell Automation 8520-GUM 9/Series CNC Grinder Operation and Programming Manual Documentation Set - Manual (Page 394)

Axis Motion
Chapter 12
12-22
During cornering, the control can perform a chamfer (a linear transition
between blocks) or a corner radius (an arc transition between blocks).
,C Chamfer size This word defines a chamfer length that connects two inter-
secting paths. Its value determines the distance that the
chamfer begins and ends from the intersection point.
,R Corner radius This word defines the radius of an arc that is tangent to two
intersecting paths.
Both the chamfer and the corner radius are generated between two motion
blocks which must be programmed in the same plane. The motion block
with the corner chamfering (,C) or the corner radius (,R) word is defined as
the first cornering block. The next motion block in the cornering plane is
defined as the second block.
If more than one ,C-- or ,R--words are programmed in the same block, the
control uses only the right--most word, and ignores others. The second
block can also have a corner chamfering or corner rounding word in it. If
it does, the second block is also used as the first block of the next corner
chamfering or corner rounding.
The chamfering and corner radius features are often used in conjunction
with QuickPath Plus. They can be programmed in either absolute (G90) or
incremental (G91) modes.
ATTENTION: If a programming error of some type is made in
the block defining the second path, the chamfer or radius is not
made. Instead the first block is executed to its programmed
endpoint without a chamfer or radius. This can cause damage to
the part or grinding wheel.
Three common error conditions that occur with corner programming are:
if a programmed block with a ,C or ,R is not followed by another
motion block in the same plane prior to the end of program, an error
results
if an MDI block with a ,C or ,R is entered it must be immediately
followed by an MDI block with motion in the same plane, or else an
error results
if more than 4 non-motion blocks are programmed immediately after a
,C or ,R block, an error results. A non-motion block is any block that
does not generate axis motion in the current plane
12.3
Chamfering and Corner
Radius