Containment Boundary set to Outside means it will cut outside the boundary.
Selecting the Plunge Outside Containment Boundary" depends on the toolpath your using. I would use Surface - Rough - Pocket and on the Rough Parameter Page, you'll find the option we're referring to.
You wont find this option on Rough - Contour or Rough Parallel.
That should do what you want.
Mike Mattera
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