Chamfer, Rounding (Chf, Chr, Rnd, Rndm, Frc, Frcm) - Siemens SINUMERIK 840D sl Programming Manual

Program code
N30 G63 Z3 M4
2.9.13

Chamfer, rounding (CHF, CHR, RND, RNDM, FRC, FRCM)

Contour corners within the active working plane can be executed as roundings or chamfers.
For optimum surface quality, a separate feedrate can be programmed for chamfer/rounding. If
a feedrate is not programmed, the standard path feedrate F will be applied.
The "Modal rounding" function can be used to round multiple contour corners in the same way
one after the other.
Syntax
Chamfer the contour corner:
G... X... Z... CHR/CHF=<value> FRC/FRCM=<value>
G... X... Z...
Round the contour corner:
G... X... Z... RND=<value> FRC=<value>
G... X... Z...
Modal rounding:
G... X... Z... RNDM=<value> FRCM=<value>
...
RNDM=0
Note
The technology (feedrate, feedrate type, M commands, etc.) for chamfer/rounding is derived
from either the previous or the next block dependent on the setting of bit 0 in machine data
MD20201 $MC_CHFRND_MODE_MASK (chamfer/rounding behavior). The recommended
setting is the derivation from the previous block (bit 0 = 1).
Meaning
CHF=... :
CHR=... :
RND=... :
NC programming
Programming Manual, 12/2019, 6FC5398-2EP40-0BA0
Chamfer the contour corner
Length of the chamfer (unit corresponding to G70/G71)
<value>:
Chamfer the contour corner
Width of the chamfer in the original direction of motion (unit correspond‐
<value>:
ing to G70/G71)
Round the contour corner
Radius of the rounding (unit corresponding to G70/G71)
<value>:
Comment
; Retraction movement: absolute Z=3mm
; Direction of rotation reversal
; Spindle with counterclockwise direction of
rotation, 200 rpm
Fundamentals
2.9 Motion commands
245