Component updates mass in part file, but not in Assembly file.

[ccopelandAYP9E]

I have a larger assembly where I was attempting to export the mass of this component to a linked excel, but I noticed that the mass will only update when inside the part file. Whenever I attempt to update the mass in the assembly that contains the component it remains "N/A". I have tried rebuilding it, changing materials, two other computers (inventor 2022 and 2023), and another user account. It seems to have occurred in parts where I used custom materials outside of the default "Autodesk Inventor Materials Library". Anyone have an idea on how to fix it?

[johnsonshiue · Accepted solution]

Hi! The part's BOM structure was set to Reference. Open the part and go to Tools -> Doc Settings -> BOM -> change the structure type from Reference to Normal. Then the mass and quantity of this part will add up in an assembly.

I think either the BOM designation was set deliberately, or it was reset by somebody in an assembly BOM table. When the BOM Structure type is changed in the BOM dialog, the change applies to the document. And, the same part will be default to Reference type else where.

If the BOM structure only needs to be changed to Reference within an assembly, such change needs to be made in the browser (right-click on the instance in the browser -> BOM Structure -> Reference).

Many thanks!