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Family table mass problem


New member
Hi to all

I have part with family table and huge number of instances. This part was created from part template in witch density was set to 7.85e-6 kg/mm3. Then I have created instances of this part. Now I wont to change density of both generic and instances parts, but strange things happened:

First I have changed density of generic part (Edit, setup. mass props, density), created mass report, and everything was fine, density was the same I entered. I saved the part, erase it from session. Then I opened this part again, generate the mass report (everything was OK), open family table and check verify, when he was finished I closed family table and created mass report once again (in generic part) and density was changed to the same density which is in instances

Then I created new material, insert my density, set it to read only, and assign it to generic part. But when I verify instances again density was changed again to one witch is in instances, and the most weird part is that the density in material file was also changed regrades file is set to read only

The third thing I have tried is to create parameter in family table mp_density (which is Alternate mass parameter of Pro/Engineer), set density in generic again to my density (8.8e-6 kg/mm3), and set in all instances to have this same density (8.8). But everything was fine until I opened assembly in witch are instances assembled and created regenerate, then all instances was back to 7.85 density in family table and in mass report.

So I'm out of options here, was someone have similar problem or toes someone know what I'm doing wrong or hove to resolve my problem?

I'm still confused hove can instances change values in generic parts??


New member
What happens when you create a weight and/or density parameter in the generic part, create a relation that uses these in a calculation, include this in the family table,and do a verify afterwards ? Including parameters in relations should force ProE to recalculate.



New member
Well this may solve the problem, but there is another thing. I have this 6 generic parts in witch are about 200 instances (in each of generic part), all those instances are assembled in one subassembly, and this subassembly is assembled in top asm. So if I will create parameter mass in generic and force to calculate mass of instances trough this parameter I will not be able to use value of this parameter in assembly (my goal is to calculate mass of top asm), or I will must create in all others parts this parameter mass to calculate mass of top assembly.

But it is also strange that parameter when changed in instances changes the parameter in generic (it would be like when you change dimension in instances which is in family table that this dimension would be changed in generic part).


New member
We used to put mp_density right in the family table. This forces massprops to be updated for each instance upon verification of the family table. I seem to recall that each had to be explicitly defined (no astrices for "same as generic). I figure using the table editor is pretty fast for even 200 instances. If most are say .283 lb/in^3, just type it once and CTRL-C downarrow CTRL-V downarrow CTRL-V etc.

Add parameter, set all values and reverify... perhaps an hour's work.

I'm stuck in 2D hell for awhile now and can't verify if this still works. I understand that there are new parameters pro_mp_density or some such. It SHOULD still work. Give it a try and let us all know.


New member
Thanks for the tip, unfortunately I haven't time to tried this what you suggest, I must finish some other projects first but when will tried I will inform you. In the meantime I solve this problem generating mass props and use its Volume then manually multiply with my density and get result. Yes I know this is manually but I was in hurry so this make results :)