Siemens SINUMERIK 840D Programming Manual page 161

3
12.97
Motion sequence when finishing (VARI=X2)
Finishing is performed in sequence from the edge
until reaching the final machining allowance on the
base, then the base is finished. If one of the final
machining allowances is equal to zero, this part of
the finishing process is skipped.
• Finishing on the edge
While finishing on the edge, the pocket is only
machined once.
For finishing on the edge the path includes one
quadrant reaching the corner radius. The radius of
this path is normally 2mm or, if "less room" is
available, equals the difference between the corner
radius and the mill radius.
If the final machining allowance on the edge is larger
than 2 mm, the approach radius is increased
accordingly.
The depth infeed is performed with G0 in the
open towards the pocket center and the starting
point of the approach path is also reached with
G0.
• Finishing on the base
During finishing on the base, the machine
performs G0 towards the pocket center until
reaching a distance equal to pocket depth + final
machining allowance + safety distance. From this
point onwards, the tool is always fed in vertically
at the depth infeed feedrate (since a tool with a
front cutting edge is used for base finishing).
The base surface of the pocket is machined
once.
© Siemens AG, 2002. All rights reserved
SINUMERIK 840D/840Di/810D Programming Guide Cycles (PGZ) – 11.02 Edition
3.9 Milling rectangular pockets – POCKET3
3
Milling Cycles
3-161