Looks Exactly the Same but different weight?

[RobJV]

Could somebody take a look at these two pipes and let me know why they each have a different mass when they can be overlayed and appear the same?

Thanks,

Rob

[blair]

They have different Volume

38.097 in 3 for ANSI #8

39.085 in 3 for ANSI #6

[RobJV]

Hi Blair,

Thanks for the reply.  I see that they have different volumes as well.  What I am trying to say is I do not understand how they have different volumes and masses as they should be the same.  It must be due to something in my FG model being microscopically not square or true which has happened to me in the past. 

- I now see that the "copy object" sketches are not exactly in line.

Rob

[RobJV]

I think something may be buggy with this FG assembly as I can reconcile the masses if I make some changes to the FG skeleton.  I have tried rebuilding the assembly and parts as well.