Please Note While Programming - HEIDENHAIN TNC 620 User Manual

4
Fixed Cycles: Tapping / Thread Milling
4.7 THREAD MILLING/COUNTERSINKING (Cycle 263, DIN/ISO:G263,
software option 19)

Please note while programming:

Program a positioning block for the starting point
(hole center) in the working plane with radius
compensation R0.
The algebraic sign of the cycle parameters depth
of thread, countersinking depth or sinking depth at
front determines the working direction. The working
direction is defined in the following sequence:
1. Thread depth
2. Countersinking depth
3. Depth at front
If you program a depth parameter to be 0, the TNC
does not execute that step.
If you want to countersink at front, define the
countersinking depth as 0.
Program the thread depth as a value smaller than the
countersinking depth by at least one-third the thread
pitch.
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!
114
positive depth is
below
TNC 620 | User's Manual Cycle Programming | 3/2014