How to get the negative of a cavity?

[Alpa]

Hello everybody,
i'm a begginer in the use of SolidWorks, so i would be grateful if you could help me step by step. I have a 3D model with a cavity; this cavity has a curved base surface very variable. In the cavity there are also some internal features at different heights. I have to get the negative (a filling) of this cavity in order to calculate the volume. Unfortunately the part is confidential so i can't post any pics. I found on the internet something similar:

View attachment 5969

Thanks very much,
Alberto

 

[Mihail]

Hi !
If you only need to calculate the volume... do this:
(related to the posted picture)
Measure the volume for the part (V1)
Create a new part (a parallelepiped) at the same length, height and width as the preview one but... without cavities.
Measure the volume for this part (V2).
The volume for the cavity is dV=V2-V1

Also you can use the COMBINE function but is hard for my English to explain this. See SW help file.

 

[Alpa]

Unfortunately i need also the filling and not only the volume. I will check COMBINE function. I hope it's easy. Any suggestion is welcome

. Thanks for your help Mihail.