Siemens SINUMERIK 840D sl Programming Manual page 487

The generated part program does not specify whether the surface to be machined is to the
right or left of the path. It is therefore assumed that the radius is a positive value and the
wear value of the original tool is a negative value. A negative wear value always describes a
tool with a lower diameter.
Using cylindrical tools
When cylindrical tools are used, infeed is only necessary if the machining surface and the
surface of limitation form an acute angle (less than 90 degrees). If a torus milling tool
(cylinder with rounded corners) is used, tool infeed in the longitudinal direction is required for
both acute and obtuse angles.
3D radius compensation with CUT3DCC, contour on the machining surface
If CUT3DCC is active with a torus milling tool, the programmed path refers to a fictitious
cylindrical milling tool having the same diameter. The resulting path reference point is shown
in the following diagram for a torus milling tool.
The angle between the machining and limitation surfaces may change from an acute to an
obtuse angle and vice versa even within the same block.
Job Planning
Programming Manual, 06/2009, 6FC5398-2BP20-0BA0
7.5 Activate 3D tool offsets (CUT3DC..., CUT3DF...)
Tool offsets
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