Please note while programming – HEIDENHAIN TNC 320 (340 55x-05) Cycle programming User Manual
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HEIDENHAIN TNC 320
109
4.7 THREAD MILLING/COUNTER
SINK
ING (Cy
c
le 263, DIN/ISO: G263)
Please note while programming:
Before programming, note the following:
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:
1st: Depth of thread
2nd: Countersinking depth
3rd: 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 positive depth is entered. This 
means that the tool moves at rapid traverse in the tool axis 
to set-up clearance below the workpiece surface!
