I don't know if this is the proper forum, but I couldn't find anything else that might be more correct, apologies if I'm in the wrong room.

I have an assembly that is compiled from 15 individual 'layers' of parts.  Each part when evaluated returns roughly 2.5 cubic inches.  Let's just say a total 37.5 cubic inches total.

However, when I evaluate the assembly, SW returns 65 cubic inches.

It is important to the client to keep the volume as low as possible, and I am supposed to give him an accurate measurement.

Due to NDA I cannot share the files here.  They are complex though.  Each layer has lots of tapers, hollows, fillets, etc.  So, manually calculating the volumes would find me playing with my rubber ducky in the corner of the closet soon enough :-).  I must rely on the algorithms from SW to do the math for me, but in this case I can't trust SW.

The question therefore is, should I trust the volume returned from the individual layers and add them manually together to find the total?  Or should I trust the assembly?

Many thanks

Carter (now going quietly to the closet)