hide unselected parts

[gtsolid]

Hello everyone
I would like to see the mass properties of a part of together, the one selected in blue: How can I hide everything I don't care?

I would also like to know if it is possible to bring back the moment of inertia of the selection compared to a diameter (i.e. to the underweight axis) that I decide

 

[MassiVonWeizen]

weight: launch the command and select only the detail that interests you; if there is already a voice inside the right button window >azzera selections and selections what interests you. alternative: right button on the affected part> island and launch mass command
Inertia: I know little, but launched the mass command in overwrite mass properties There is replace moment of inertia

 

[gtsolid]

works, thanks