Is there a setting to create bodies at a specific density?

[Kenja824]

In NX9, in Preferences - Modeling, (General), there is a Density setting. Everyone here has the setting at 99999.00 and "Kg/Cu M".
However, if we use the Structural Shapes program to create a simple block at 127mm x 127mm x 13mm, then do a Measure Bodies on the block immediately, some of us will get a Mass of 20.967kg (which is way too high) and others will get the correct Mass of 1.642 kg.

This tells me there must be another place to set the density so that bodies are created to the correct wgt, but I have not been able to figure it out.

As it stands, we usually run the stock size program and it fixes the wgt, but it just seems to me that it would be best if all of us had their solid bodies being created at the correct wgt.

Any ideas?

 

[SDETERS]

Have you checked the attributes on the solid body? Does the solid body have a material attribute assigned to it?

 

[Kenja824]

No attributes. It can be a freshly made block and no attributes added to it yet. If I do an info object and select the solid body, it has a density of .000099999. A b;lock the size mentioned above automatically is made at 20.967kg. But some can make the exact same size block and it is made at 1.642kg.

 

[Arkance/PhoeNX]

If you and your other users do an Information -> Object on the solid block, what density is reported? Do the values differ?


Anthony Galante
Senior Support Engineer


NX3 to NX10 with almost every MR (21versions)

 

[JohnRBaker]

I suspect that there are templates files involved here which were created using the original, out-of-the-box default density, which we decided years ago to set to the value for 'mild steel', a reasonable compromise under the circumstances.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Digital Factory
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.

 

[Arkance/PhoeNX]

@JohnRBaker, that's what I'm guessing, but he did say:

In NX9, in Preferences - Modeling, (General), there is a Density setting. Everyone here has the setting at 99999.00 and "Kg/Cu M".

My expectation is that if the Preferences -> Modeling density value is the same, then the templates are set the same, that's why I' curious what the solid density actually is.



Anthony Galante
Senior Support Engineer


NX3 to NX10 with almost every MR (21versions)

 

[JohnRBaker]

There are ONLY two ways, that I'm aware of, that will set the specific density of a body. The first is...

Customer Defaults -> Modeling -> Solid Modeling -> Mass and Density

...which I've already mentioned is set, out-of-the-box, to the value for mild steel.

The second is by assigning the solid body a Material using the...

Tools -> Materials -> Assign Materials...

...function.

Actually there is a third way, and that is by using the...

Analysis -> Advanced Mass Properties -> Advanced Weight Management...

...where you can 'assert' values for such things as Mass, Density and/or Volume.

Note that while teh Customer Default and Material assignment route both applies the density directly to a solid body, in the case of doing an 'assertion', it assigned to the Part File itself or a specific Reference Set, irrespective to what was assigned to the solid body(s) in the part file.

As for determining what specific density was assigned to any specific SOLID body, simply go to...

Information -> Object...

...select the Solid Body and press OK and you'll get a info list which will include the specific density assigned to the solid body, be it due ti the Customer Default value or as result of assigning it a Material. Note however, if a 'Density' was asserted, as describe above in my 'third way' comment, this would NOT be reflected in the Information listing.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Digital Factory
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.

 

[cowski]

There are ONLY two ways, that I'm aware of, that will set the specific density of a body.

Perhaps it is hidden in newer versions, but there is also Edit -> Feature -> solid density...
Though I doubt this method is a factor in Kenja824's case...

www.nxjournaling.com

 

[Kenja824]

Some people create bodies already with the correct density. Others create them at the wrong density.
Yesterday I was getting the wrong density. Today I am getting the correct density.

Those two points tells me it has to be in our license bundles. We have three bundles and each is a bit different than the other with different licenses and such. (I dont know why but my knowledge doesnt go in that direction.) But obviously one of the bundles has a different setting than the others.

Unfortunately every time I try to match settings between mine and a computer I know is getting the wrong density, they dont seem different.

Customer Defaults -> Modeling -> Solid Modeling -> Mass and Density: I thought this would be it. But it seems that both computers have the same settings on all three (Site, Group & User).

Tools -> Materials -> Assign Materials... : This one seems to be set up where you have to manually add the material. Our density problem is in place automatically when we create the body somehow.

Analysis -> Advanced Mass Properties -> Advanced Weight Management... : This one also appears to be a manual change.

Edit -> Feature -> solid density... : cowski you are right. This one I use all the time for some stuff I do, but again, since it is a manual change you need to make to a body, it cant be it.

So far, unless I am mistaken with one of these settings, the only one that would give a density to solid bodies upon creation, would be the first setting in Customer Defaults. So I cant figure out why these are the same between our computers if we get different densities. Plus, since mine was incorrect yesterday and correct today, but I used the same file, this tells me it has nothing to wo with the possibility of older files compared to newer files.

This is not a huge issue. We usually assign materials or density to the models at one point or another anyway. But having this problem worries me of a chance of a future weight problem that might sneak through, so I am trying to figure it out as I work on my other stuff.

 

[cowski]

Customer defaults will only affect new (blank) files. If you are using templates or editing an existing file, check the modeling preferences Preferences -> Modeling -> general -> density and density units options.

www.nxjournaling.com

 

[Toost]

Are your users using the same templates ?
are the templates local or from a common server ?

In NX go Help - NX Logfile, In the listing window search for "File New Templates" and you will see all templates reported, with directory names or teamcenter IDs ( depending on your environment) .

Open this templatefile using the name/directory and check the density. ( or the Teamcenter ID )

Regards,
Tomas

 

[JohnRBaker]

OH, and let's not forget...

Preferences -> Modeling -> General

...where you can override, once a part is open, the Customer Default setting for specific density.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Digital Factory
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.

 

[Kenja824]

Yesterday it was wrong for me. Today it is right. However, I have now found that two different files had it set differently. So I no longer am sure if I checked it in the same file today as I did yesterday. I was sure I had, but now I am questioning myself. lol

We are supposed to all be using the same template, but there is no guarantee they are. Is there a way to check a particulr file to see what template it was started with?

 

[JohnRBaker]

You could look at the Part History.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Digital Factory
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.