Create object outline

Hi there!
I would like to ask you for advice regarding an outline of an object I would like to create so the cnc can fillet the specific edges.
I would like an outline like this

Where it does not extend into the grooves of the object, but when I use commands like extractwireframe or Silhouette it creates curves around edges I dont want it to

Is there anyway around this maybe through a plugin or GH?

There’s no real way for Rhino to know what you want to cut and what you don’t - for that it would have to read your mind.

You can use DuplicateFaceBorder on one of the large flat faces to get a single outline of the object in 2D. It’s then pretty simple to edit the curves to remove the parts you don’t want to cut.

Yeah, I was afraid of that… It is pretty easy to edit the geometry in one object, its just that I have a lot that I need to do the same thing with.

Maybe I am thinking about this all wrong. The aim of this for the cnc fillet the outer only edges, but maybe there is an action inside a cam program that would take care of that.
Thank you again,

If your parts are cut on a CNC with a flat table as opposed to multiple vacuum units, the machine can’t fillet the bottom edges.

Another problem is the thickness of the plywood which hardly ever is exactly let’s say 18 mm but a bit less. That means your fillet won’t look nice if your machine thinks it’s exactly 18 mm. If you set the machine exactly to the correct thickness it will work fine but that would require verifying the thickness of all your stockmaterial. Or the machine has a fillet tool that adjusts to the perfect height automatically. But you still won’t be able fillet the bottom edges.

In most situations it will be quicker to fillet the edges with a router.

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Hi Aspasia -

By the looks of that, you could extract the “upper” surface, shrink it, and untrim on pretty much all of those. That would then leave the more special ones.

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Maybe you could try offsetting those solids outward enough that the details you don’t want get eliminated, then offset inward by the same number. (You might need to run Cap and MergeAllFaces before the offset inward.) You could do most of that in a macro (or pretty easily with a script, I think.)

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This totally works! Thank you so much! It is such a smart suggestion. !