Not sure what to call what I want to do so ... I'll just dive in...
I imported a 3D terrain model and want to "mask" as section of it, marked in yellow on the attached thumbnail, so that it's not carved with the model's tool path. The masked area would become a pocket on a separate tool path.
I'm my simple mind, I'd draw the rectangle and push a "delete all" vectors inside the rectangle button. But ... it doesn't seem like it works that way. I can carve a deep pocket in the model using that rectangular vector, but that's too deep - the high Z on the terrain model is 3.1", the job thickness is 4" and I'd want the bottom Z on the 'masked pocket" at about 1/2".
Can anybody who gets my drift helps sort this for me?