I think that by working on a surface by limiting the surface of the mold with the surface of the part, and then by shifting this surface to the desired places, it is quite possible to have a usable rendering.
If it is only certain parts of the surface to be offset, you just have to draw a sketch and then limit the surface according to the sketch so that you can offset only that part.
Hello
For example, you have to use the intelligent components of solidworks to automate the creation of the machining associated with the components.
edit: http://m.youtube.com/watch?v=ddYn0gJP48A&desktop_uri=%2Fwatch%3Fv%3DddYn0gJP48A
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