negative of the piece

[MaiMollare]

Hello everyone
work in the centrifugal compressor industry, I must create the negative of a volute and a impeller connected to it, i.e. in practice I must create the air passage zone. I wanted to know if there was any option unknown to me to get to this result, or if I have to copy all the surfaces one by one for a clay them and then solidify them.what I am able to do but that is really Moroccan.
hello and thanks to anyone who wants to help me.
p.s.
use the w3

 

[Prof.]

from the assist: change > operation with components >

 

[MaiMollare]

Thank you very much
I managed only now to try the command you recommended me and it works, but I add to pay attention to the acuracy of the 2 pieces, because if they are not equal the command does not perform the cut out
Hi.

 

[Prof.]

It is true, in all operations between components, precision must correspond.
Bye.