Specifying Contour Elements In Polar Coordinates - Siemens SINUMERIK 808D Milling Programming And Operating Manual

4.5.5

Specifying contour elements in polar coordinates

Functionality
The description about defining the coordinates of contour elements applies to the
specification of positional data in the Cartesian coordinate system. Alternatively, you have
the option to define positions using polar coordinates.
When programming contours, you can define a pole at any time prior to using polar
coordinates for the first time. Programmed polar coordinates subsequently refer to this pole.
The pole is modal and can be re-defined at any time. It is always entered in absolute
Cartesian coordinates. The contour calculator converts values entered as polar coordinates
into Cartesian coordinates. Positions can be programmed in polar coordinates only after a
pole has been specified. The pole input does not generate a code for the NC program.
Pole
The polar coordinates are valid in the level selected with G17 to G19.
The pole is a contour element that can be edited, which itself does not contribute to the
contour. It can be entered when the starting point of the contour is defined or anywhere
within the contour. The pole cannot be created before the starting point of the contour.
This softkey allows you to specify a pole and can only be entered in absolute Cartesian
coordinates. This softkey is also present in the starting point screen. This enables the pole to
be entered at the start of a contour, so that the first contour element can be entered in polar
coordinates.
Further notes
If the straight line that was generated with close contour is linked to the start element of the
contour with a radius or chamfer, the radius or chamfer must be specified explicitly as
follows:
● Close contour, input key, enter radius/chamfer, accept element. The result then
Input switchover: Cartesian/polar
The following contour elements can be entered optionally in polar coordinates only after a
pole has been defined, whether this was done at the outset or later in the process:
● Circular arcs,
● Straight lines (horizontal, vertical, any direction)
To switchover between Cartesian and polar coordinates, additional toggle fields are
displayed in the programming windows for the contour elements of oblique lines and circular
arcs.
Milling Part 1: Operation
Programming and Operating Manual, 12/2012, 6FC5398-4DP10-0BA0
corresponds exactly to what would occur if the closing element were to be entered with
the radius or chamfer.
Close contour can only be used for entering contour elements in polar coordinates if the
starting point of the contour was set to polar and the same pole is still valid when the
contour is closed.
Part programming
4.5 Free contour programming
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