HEIDENHAIN TNC 620 User Manual page 293

Setting a datum
The datum of the drawing for the DXF file is not always located in
a manner that lets you use it directly as a datum for the workpiece.
Therefore, the TNC has a function with which you can shift the
drawing datum to a suitable location by clicking an element.
You can define a datum at the following locations:
By directly inputting numerical values into the List View window
At the beginning, end or center of a straight line
At the beginning, center or end of a circular arc
At the transition between quadrants or at the center of a
complete circle
At the intersection between:
A straight line and a straight line, even if the intersection is
actually on the extension of one of the lines
Straight line – circular arc
Straight line – full circle
Circle – circle (regardless of whether a circular arc or a full
circle)
You must use the touchpad or a connected mouse in
order to specify a reference point.
You can also change the reference point once you
have already selected the contour. The TNC does not
calculate the actual contour data until you save the
selected contour in a contour program.
Selecting a datum on a single element
Select the mode for specifying the datum
Click the desired element with the mouse: The
TNC indicates possible locations for datums on the
selected element with stars
Click the star you want to select as reference
point. The TNC sets the reference-point symbol to
the selected location. If the selected element is
too small, then use the zoom function.
HEIDENHAIN | TNC 620 | ISO Programming User's Manual | 9/2016
DXF converter (option 42)
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7.3
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