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- Start with a solid like this, with a closed profile within one of the inside facets.
- Activate Imprint. For the sake of comparison, first select Auto Detect. In this example, the last two options in the Inspector Bar have no blend (fillet or chamfer).
- Select the inner face that contains the profile, then select the profile itself. Extrude the profile this way:
This is the result: because the profile was extruded inward with respect to its face, its extrusion was subtracted from the solid.
- Undo, and now select Add.
- Select and extrude the profile the same way, and now its extrusion is added to the solid.
