Lifting On Retraction (Lftxt, Lfwp, Lfpos, Polf, Polfmask; Polfmlin) - Siemens SINUMERIK 840Di sl Programming Manual

Example of deactivating fast retraction before tapping.
N55 M3 S500 G90 G0 X0 Z0
...
N87 MSG ("tapping")
N88 LFOF
N89 CYCLE...
N90 MSG ("")
...
N99 M30
Trigger criteria for retraction
• Fast inputs, programmable with SETINT LIFTFAST (if LIFTFAST option is enabled)
• NC Stop/NC Reset
If fast retraction is enabled with LFON, it is active for every movement
Retraction path (DILF)
The retraction path can be defined in the machine data or by programming. After NC Reset,
the value in MD 21200: LIFTFAST_DIST is still active.
Retraction direction (ALF)
The retraction direction is controlled in conjunction with ALF with keywords LFTXT, LFWP
and LFPOS . With LFTXT, the retraction is defined in the tool direction for ALF=1. LFTXT
(tangential lifting in tool direction) is set as default. See "Lifting in retraction with LFTXT,
LFWP, LFPOS, POLF, POLFMADK and POLFMLIN".
4.19.2

Lifting on retraction (LFTXT, LFWP, LFPOS, POLF, POLFMASK; POLFMLIN)

Function
With the LFTXT, LFWP, LFPOS; POLF commands you can selectively program on lifting the
retraction processing from the lift movement up to the lift position. The following are
programmed:
• Retraction direction from the path tangent or the active working plane
• Retraction direction toward position programmed
• Absolute retraction position
In this case, the axis relation of the programmed path or the linear retracting movement is
not always guaranteed for a certain period of time. The linear relation cannot always be
produced according to the dynamic behavior of all participating axes up to reaching the lift
Fundamentals
Programming Manual, 11/2006, 6FC5398-1BP10-2BA0
4.19 Stop with thread cutting (LFOF, LFON, LFTXT, LFWP, LFPOS)
Motion commands
;Deactivate fast retraction before ;tapping.
;Tapping cycle with G33
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