Corners In Face Milling - Siemens SINUMERIK 840D sl Function Manual

migrate from the tool tip to the periphery (at outside corners or convex surfaces) or the paths
must be shortened to prevent contour violations (at inside corners or concave surfaces).
It is therefore necessary to activate both the smoothing of the contours ("Top Surface" function)
and the smoothing of the surface normal to ensure that the transitions run smoothly.
3.1.3.4

Corners in face milling

Two surfaces that do not tangentially transition into one another form an edge. The paths
defined on the surfaces form a corner. This corner is a point of the edge.
The type of corner (inside or outside corner) is defined by the surface normals of the
participating surfaces and the paths defined on them.
The surface normals of the two surfaces forming the edge may point in opposite directions of
the overall surface (the front edge of one surface is continued on the rear edge of the second
surface), see also the following Figure. Transitions of this type are not allowed and are rejected
with an alarm.
The scalar product of the surface normal vector and (possibly variable) tool orientation on one
corner/path must be positive at each point, i.e. it is not permissible to machine from the rear face
of the surface. If this condition is not fulfilled, an alarm is output. The permissible ranges of
validity of tool orientation for inside and outside corners are illustrated in the following Figure.
These ranges are further restricted by the condition that the angle between the surfaces to be
machined and the "steepest" surface line of the tool surface must not be lower than a particular
machine data setting. The "steepest" surface line is a line at angle a to the tool longitudinal axis
(this line is in the same direction as the tool longitudinal axis on cylindrical tools). This restriction
must be imposed to ensure that the contact point on the tool does not leave the permissible
range.
Figure 3-7
It is possible to insert blocks that contain no motion commands (e.g. auxiliary function outputs)
and/or that include motions of geometry axes not involved in the path between two blocks which
contain a path definition. In particular, orientation changes can also be programmed in such
blocks. The only exception applies to the activation and deactivation of the 3D tool radius
compensation function: Intermediate bocks with orientation changes are not permitted
Tools
Function Manual, 06/2019, A5E47435126B AA
Corners in face milling
W5: 3D tool radius compensation
3.1 Function
249