General information about CNC
Version 1.1.2 dated 2019-05-07
Page 248
Translation of the original instructions
macines name
GB
C
NC_g
ener
al_in
fo
rmat
ion_mi
lling_
GB.
fm
OPTIMUM
M A S C H I N E N - G E R M A N Y
®
4.2.2
Polar coordinate system
In the Cartesian coordinate system a point is described by e.g. its X- and Y-coordinate. For
rotation-symmetric outlines, e.g. circular drilling images the required coordinates can only be
calculated with considerable effort.
In the polar coordinate system a point is described by means of its distance (radius r) to the
coordinate origin and its angle (a) to the defined axis. The angle (a) is related to the X-axis of
the X, Y coordinate system. In opposite direction it is negative.
4.2.3
Machine coordinate system
The machine coordinate system of the CNC machine tool is determined by the manufacturer. It
cannot be changed. The position of the origin point for the machine coordinate system, also
called machine zero point cannot be changed.
Any tool moves are generally defined in a standardized, right-handed coordinate system.
Turns from +X to +Y are created in +Z direction, which result in a right-handed screw.
Z-axis:
According to the standard it is
equal to the working spindle or
continues in positive direction
starting from the workpiece.For
milling it continues directed to the
spindle perpendicular on the
clamping surface (only for perpen-
dicular milling machines) for sev-
eral spindles one main spindle is
determined.
X-axis:
Continues horizontally and paral-
lel to the clamping surface
for vertical Z-axis: +X to the right
for horizontal Z-axis: +X to the left
.
Img.4-1:
Vertical Z-axis
Y-axis:
At a right angle to the Z- and X- axis in a way that a right-handed coordinate system is resulting
4.2.4
Workpiece coordinate system
The workpiece coordinate system is determined by the programmer. It can be changed. The
location of the origin point for this workpiece coordinate system, also called workpiece origin
point is generally user-defined.
