HEIDENHAIN TNC 310 (286 140) - Manual (Page 146)

8 Programming: Cycles 134
RULED SURFACE (Cycle 231)
1 From the current position, the TNC positions the tool in a linear 3-
D movement to the starting point .
2 The tool subsequently advances to the stopping point at the
feed rate for milling.
3 From this point, the tool moves in rapid traverse FMAX by the tool
diameter in the positive tool axis direction, and then back to
starting point .
4 At the starting position the TNC moves the tool back to the the
last traversed Z value.
5 Then the TNC moves the tool in all three axes from point in the
direction of point to the next line.
6 From this point, the tool moves to the stopping point on this
pass. The TNC calculates the stopping point using point and an
offset in the direction of point
7 Multipass milling is repeated until the programmed surface has
been completed.
8 At the end of the cycle, the tool is positioned above the highest
programmed point in the tool axis, offset by the tool diameter.
Cutting motion
You can freely choose the starting point and thus the milling
direction since the TNC always performs the individual cuts from
point to point and the process sequence is executed from
point / to point / . You can position point in any corner of
the surface to be machined.
If you are using an end mill for the machining operation, you can
optimize the surface finish in the following ways
■ a shaping cut (tool axis coordinate of point greater than tool
axis coordinate of point ) for slightly inclined surfaces.
■ a drawing cut (tool axis coordinate of point less than tool axis
coordinate of point ) for steep surfaces
■ When milling twisted surfaces, program the main cutting
direction (from point to point ) parallel to the direction of the
steeper inclination. See figure at center right.
If you are using a spherical cutter for the machining operation, you
can optimize the surface finish in the following way
■ When milling twisted surfaces, program the main cutting
direction (from point to point ) perpendicular to the direction
of the steeper inclination. See figure at lower right.
8.5 Cycles for Multipass Milling
X
Y
Z
X
Y
Z
X
Y
Z