HEIDENHAIN TNC 426 (280 476) - Manual (Page 169)

142 6 Programming: Programming Contours
6.4 P
a
th Cont
ours
—
Car
tesian Coor
dinat
e
s
Corner rounding RND
The RND function is used for rounding off corners.
The tool moves on an arc that is tangentially connected to both the
preceding and subsequent contour elements.
The rounding arc must be large enough to accommodate the tool.
7 7 7 7 Rounding-off radius : Enter the radius
Further entries, if necessary:
7 7 7 7 Feed rate F (only effective in RND block)
Example NC blocks
5 L X+10 Y+40 RL F300 M3
6 L X+40 Y+25
7 RND R5 F100
8 L X+10 Y+5
In the preceding and subsequent contour elements, both
coordinates must lie in the plane of the rounding arc. If
you machine the contour without tool-radius
compensation, you must program both coordinates in the
working plane.
The corner point is cut off by the rounding arc and is not
part of the contour.
A feed rate programmed in the RND block is effective only
in that block. After the RND block, the previous feed rate
becomes effective again.
You can also use an RND block for a tangential contour
approach if you do not want to use an APPR function.
X
Y
40
40
R5
5
10
25