I am attempting to use the Mass Properties in Solidworks to calc the volume of a hollow container. It is currently telling me that the volume is about 1/10 of what I know it to be. Any suggestions? Thanks. Nat
Are you trying to calculate the volume of the container or the cavity inside the container?
If you want the cavity inside the container, reverse your shell process so you create a solid of the cavity. Then apply a density to arrive at the mass - or skip this to get the volume. In either case make sure you use the correct units so you don’t “miss Mars”.
I hope this helps…
Yea, I made that mistake recently. I was designing a 4L bottle and couldn’t figure out whey mass properties was telling me it was less than 1L. It was measuring the volume of the material, not the inside of the shell… Doh! 
Surpressed the shell feature and got the right numbers…
first bring the mass properties dialogue box up. it might show a part name, clear that. once the box is empty click on the feature (if it’s a cut, cut loft, or a shell) that defines the volume and you see the volume calculated in the box.