Please Note While Programming - HEIDENHAIN TNC 640 User Manual

4
Fixed Cycles: Tapping / Thread Milling | HELICAL THREAD DRILLING/MILLING (Cycle 265, DIN/ISO: G265)

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 or sinking depth at front determines the
working direction. The working direction is defined in
the following sequence:
1. Thread depth
2. Depth at front
If you program a depth parameter to be 0, the TNC does
not execute that step.
If you change the thread depth, the TNC automatically
changes the starting point for the helical movement.
The type of milling (up-cut/climb) is determined by the
thread (right-hand/left-hand) and the direction of tool
rotation, since it is only possible to work in the direction
of the tool.
Danger of collision!
If you enter a positive depth with a cycle, the TNC reverses
calculation of the pre-positioning. This means that the tool
moves at rapid traverse in the tool axis to set-up clearance
below the workpiece surface!
Enter depth as negative
Enter in machine parameter displayDepthErr (No. 201003)
whether the TNC should output an error message (on) or not
(off) if a positive depth is entered
148
NOTICE
HEIDENHAIN | User's manual for cycle programming | 10/2017