HEIDENHAIN TNC 620 User Manual page 160

5
Fixed Cycles: Pocket Milling / Stud Milling / Slot Milling
5.7 CIRCULAR STUD (Cycle 257, DIN/ISO: G257)
Danger of collision!
Use the machine parameter displayDepthErr to
define whether, if a positive depth is entered, the
TNC should output an error message (on) or not (off).
Keep in mind that the TNC reverses the calculation
for pre-positioning when a
entered. This means that the tool moves at rapid
traverse in the tool axis to set-up clearance
the workpiece surface!
The TNC performs an approach motion in this cycle!
Depending on the starting angle Q376, the following
amount of space must be left next to the stud: At
least tool diameter + 2 mm. Danger of collision!
At the end, the TNC positions the tool back to the
set-up clearance, or to the 2nd set-up clearance if
one was programmed. The end position of the tool
after the cycle differs from the starting position!
Enter a starting angle between 0° and 360° in
parameter Q376 in order to determine the exact
starting position. If you use the default value -1 the
TNC automatically calculates the most favorable
starting position. These may vary
160
positive depth is
below
HEIDENHAIN | TNC 620 | User's manual for cycle programming | 9/2015