Calculating milling paths for undercut areas

This trim steel has undercut areas in the tilt direction. I use separation surfaces to limit the milling area to prevent too much milling in the air when re-roughing with the "Nc3axJob/RPlan" function. Is there an easier way?

Yes. If you view the blank only from the tilt direction, milling areas are generated to the deepest point in the blank in the tilt direction. This can also result in milling paths being determined for areas that no longer have to be machined. As of Version 4.0 Release 4, it is possible to view blanks from different directions for calculating the milling areas. Viewing from two sides is recommended in your example.

Here's how you do it


Open the "Elements" dialog for the corresponding NCJob in the Job Manager.


Select the "Two-sided" option for the "View" parameter.


Start the calculation. The blank is viewed in both the tilt direction (red) as well as in the opposite direction (blue) for determining the milling areas. The corresponding milling areas are combined with each other. This prevents machining operations without contact.


In addition to the "One-sided" and "Two-sided" options, the "Exact" option can be used to determine the exact contour of the blank. This option is recommended, for example, for blanks where areas that have already been machined are completely covered (Determine blank exactly for milling paths). Note that calculation with the "Exact" option takes considerably longer.

You can learn more about viewing blanks with undercuts by calling up the context-sensitive help for the "View" parameter in the "Blank" area of the "Elements" dialog.


Register for the Tebis newsletter and stay up to date.

Register for seminars & trainings

Better utilize potentials and reach goals sooner

  • Tebis Base

    CAD/CAM standard  (On request) Read more

  • Tool management

    CAD/CAM key users  (On request) Read more

  • Project management basics

    Organization and efficiency  (On request) Read more