HEIDENHAIN TNC 426 (280 476) Pilot - Manual (Page 66)

67
SL
Cycles
SL Cycles
General Information
SL cycles are useful when you wish to machine a contour consisting of
several subcontours (up to 12 islands or pockets).
The subcontours are defined in subprograms.
When working with subcontours, always remember:
• For a pocket the tool machines an inside contour, for an
island it is an outside contour!
• Tool approach and departure as well as infeed in the
tool axis cannot be programmed in SL cycles!
• Each contour listed in Cycle 14 CONTOUR GEOMETRY
must be a closed contour!
• There is a limit to the amount of memory an SL cycle can
occupy! A maximum of 128 straight line blocks, for example,
can be programmed in an SL cycle.
The contour for cycle 25 CONTOUR TRAIN must not be
closed!
Make a graphic test run before actually machining a part. That
way you can be sure that you defined the contour correctly!