HEIDENHAIN ITNC 530 - PILOT SMART NC Manual page 177

FK free contour programming
Workpiece drawings that are not dimensioned for NC often contain
unconventional coordinate data that cannot be entered with the gray path
function keys.
You can enter such dimensional data directly by using the FK free contour
programming function. The TNC calculates the contour from the known
contour information that you entered in the form. The following functions
are available:
Function
Straight line with tangential connection
Straight line without tangential connection
Circular arc with tangential connection
Circular arc without tangential connection
Pole for FK programming
Information about possible contour entries are in the tooltip
that the TNC displays for each entry field (see "Mouse
operation" on page 40) and in the User's Manual for
Conversational Programming.
Soft key
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