Siemens SINUMERIK User Manual page 195

Starting point
The cycle determines the starting point for the machining operation automatically. The starting point is located in the axis in
which the depth infeed is carried out, shifted from the contour by the amount of the finishing allowance + lift-off distance
(parameter _VRT). In the other axis, it is by finishing allowance + _VRT ahead of the contour starting point.
When the starting point is approached, the cutter radius compensation is selected internally in the cycle.
The last point before the cycle is called must therefore be selected such that this approach is possible without collision and
space enough is provided to carry out the appropriate compensatory motion.
See the following illustration for starting point:
Cycle approach strategy
In roughing, the starting point determined by the cycle is always approached with both axes simultaneously, and in finishing,
axis by axis. In finishing, the infeed axis traverses first.
Programming example 1: Stock removal cycle
The contour shown in the illustration to explain the defining parameters is to be machined longitudinally externally by
complete machining. Axis-specific finishing allowances are specified. Cutting will not be interrupted when roughing. The
maximum infeed is 5 mm.
The contour is stored in a separate program.
Programming and Operating Manual (Turning)
195
01/2017