The next step is to machine the two counterbores at the top left and right corners of the part.
2D Milling panel
Bore
.
button and select the tool #2 - Ø8 mm flat from the library.
to close the Tool Library dialog. 
at the bottom of the Operation dialog box, or right-click in the graphics window and select OK from the marking menu, to automatically start calculating the toolpath. The toolpath is now calculated and shown in the graphics window.

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