HEIDENHAIN iTNC 530 (340 420) ISO programming - Manual (Page 304)

304 8 Programming: Cycles
8.6 SL Cy
cles Gr
oup I
ROUGH-OUT (Cycle G57)
Process
1 The TNC positions the tool in the working plane above the first
cutting point, taking the finishing allowance into consideration.
2 The TNC moves the tool at the feed rate for plunging to the first
plunging depth.
The contour is fully rough-milled (see figure at top right):
1 The tool mills the first subcontour at the programmed feed rate,
taking the finishing allowance in the machining plane into
consideration.
2 Further depths and further subcontours are milled by the TNC in
the same way.
3 The TNC moves the tool in the spindle axis to the set-up clearance
and then positions it above the first cutter infeed point in the
machining plane.
Rough out pocket (see figure at center right):
1 After reaching the first plunging depth, the tool mills the contour at
the programmed feed rate paraxially or at the entered roughing
angle.
2 The island contours (here: C/D) are traversed at set-up clearance.
3 This process is repeated until the programmed milling depth is
reached.
Before programming, note the following:
With MP7420.0 and MP7420.1 you define how the TNC
should machine the contour (see “General User
Parameters” on page 466).
Program a positioning block for the starting point in the
tool axis (set-up clearance above the workpiece surface).
This cycle requires a center-cut end mill (ISO 1641) or pilot
drilling with Cycle 21.