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Part Mass Properties

donha

New member
Does anyone know if it still necessary to input through Program:



MASSPROP

PART nnnnnnn.prt

END MASSPROP



Does anyone know why this must be done? I see threads on calculating Mass Properties and don't see this as a necessity.
 

jabbadeus

New member
Nope, not necessary.



You only need to choose Analysis > Model Analysis > Mass Properties to generate the calculations. If a material density is not assigned, Pro will prompt you for a value.
 

Brian_Adkins

Moderator
I think that is still a valid method for recalculating mass-props after every model regeneration. The downside of this method was that, if you rename the part, you would need to manually updated the program to reflect the new name.



However, I think you can get the same effect with an evaluate feature.



-Brian
 

Israr

Active member
Jabbadeus,



I quote your reply to this posting for my question:



You only need to choose Analysis > Model Analysis > Mass Properties to generate the calculations. If a material density is not assigned, Pro will prompt you for a value.



But I have seen a problem in both 2001 and WF that once you assign a material density to a part or parts in assembly this way and you want to change the density, it does not give you option. What I do is assign material to each part in assembly.

Have you observed this thing?



Israr
 

Israr

Active member
kvision,



If you carefully read my reply, you will notice that what

my question is about the problem with this



Analysis > Model Analysis > Mass Properties



Once you assign density it prompts for;

then it does not allow you to change this way , I mean it should prompt like



Do you want to change density or continue with the current?



Which I think programmers should include in the next releases.



Israr
 

airion

New member
Israr,



I think a prompt every time you ran mass properties would be annoying. It clearly shows you right in that window what the density is. Having said that, I do think it would make sense to be able to change the density right from the mass properties.
 

kvision

Moderator
Good modeling techniques would normally have you assign your material properties to each part as it is created. If you didn't and then at the assembly level asssign them then you need to go back to part mode and use setup>density to change it. If you assign a material first and then change the density it changes the density of the current model but does'nt alter the material file on your hard drive.

Do you want to change density or continue with the current?



To get this question you could set up input statements in your assembly program and then use relations to set the density each time and it will ask to enter new values or use current , but why would you want to?

Do you REALLY want to enter densities for what may be an assembly of hundreds or thousands of parts and sub-assemblies?If you really need to change a few densities just open them up and set them again.
 

Israr

Active member
kinetivision,



You are right, its there in WF 2.0 but its production release is yet to come.



Israr
 

jabbadeus

New member
Replying to Israr's post, kvision is correct. In WF and previous versions, you could always change density and mass properties. In 2001 and previous versions, it was from the Setup command in the menu manager.
 

kvision

Moderator
To set density in WF (1.0) use edit>setup>mass props then in the dialog box pick select Geometry and Parameters from the first drop down list and then you can enter the density.
 

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