Livio Cioffi

Hi everyone .. I can't transform a stl from mesh to nurbs to be able to work on volumes or better, it transforms but it gives me problems in boolean operations ... then, I could extrude an internal oval face so as to make the hole smaller ?

Hi everyone, I want to subtract a solid volume completely inserted in another solid ... for example from a sphere, I would like to subtract another smaller sphere having the same center so as to have a closed sphere but hollow / empty inside, like can i do it in rhino? the boolean difference tells me it's impossible as the volumes don't intersect!