Component excluded from reference set

[SiW979]

I'm doing some run-of-the-mill top down modelling in an assembly, for example extracting some edge curves, creating a new component within one of the sub assemblies using and selecting the extracted edges as the basis of the new part. I then make the new part the displayed part, complete the model, save it and then switch back to the master assembly expecting to see my new master piece in place but insteaf the new part is now blanked. If I try and click on the component to make it visible NX tells me "This component cannont be made visible it is in an excluded reference set" To rectify this I have to make the parent the displayed part, click on format > reference sets, select solid and then add the new part to the solid reference set and save the parent.

Why is this happening and how can I stop this from happening? Many thanks in advance.

Best regards

Simon (NX4.0.4.2 MP4 - TCEng 9.1.3.6.c)

http://www.jcb.com

Life shouldn't be measured by the number of breaths you take, but rather how many times it's taken away...

 

[phillpd]

There's a Customer Default under Assemblies for "Add New Components Automatically" that may help you.

Specialty Engineered Automation (SEA)

http://www.sea4ug.com

a UGS Foundation Partner

 

[PheasantPlucker]

Simon,
Is "solid" a reference set that is common to both parts? If not, it won't show up when you switch back. Try using model as a reference set in both parts and it should show up automatically.

 

[JohnRBaker]

While there are no 'technical' reasons why Reference Sets should NOT be created in an Assembly, there are nonetheless several reasons why this practice should be avoided. For one thing, as you've already discovered, Reference Sets act as 'filters' and while this might be easy to spot and rectify in product models with a shallow assembly structure, once things become more complex with several levels of assemblies, this filtering behavior can become very painful and hard to detect, particularly when making changes (adding or removing Components to a Reference Set) inside of sub-assemblies after the overall assembly has been created and established.

John R. Baker, P.E.
Product 'Evangelist'
NX Design
Siemens PLM Software Inc.
Cypress, CA

http://www.siemens.com/plm

http://www.plmworld.org/museum/

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

 

[JohnRBaker]

Simon,

Can you please contact me off-line via email at john.r.baker@... (you should be able to figure out the rest) as I have an issue that I would like to discuss with you.

John R. Baker, P.E.
Product 'Evangelist'
NX Design
Siemens PLM Software Inc.
Cypress, CA

http://www.siemens.com/plm

http://www.plmworld.org/museum/

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

 

[hudson888]

Simon,

Firstly I agree with John's earlier response and as I've said elsewhere many sites don't like using reference sets in assemblies. You mentioned that there is a sub-assembly involved and that is usually where the problems start.

If you have any component it already has two reference sets empty and entire part, then you add a couple more lets say SOLID and REP so most people will know what they refer to.

You can't really see REP at all while the component containing it is the displayed part. In fact what you see is exclusively the entire part reference set. From the displayed part you probably filter entire part to that you're looking at a subset of it while the construction geometry remains hidden or on other layers. It is only when you create an assembly of several such components that you can see the reference sets working.

So now you have created an assembly if you then change the component's reference sets to SOLID and create a reference set in the assembly called SOLID then do the same procedure for REP then you're duplicating the intent of the automatic process.

The problem comes when you add your assembly as a sub-assembly to another "top" assembly. From there the potential exists to load SOLID and get solids displayed then change the reference set of the sub-assembly to REP and in doing so effectively also change the reference sets of all the components to REP. So far so good. But you could also select the components from the tree and change the reference set of one of them to empty, making the geometry disappear. The problem there is that some people will unknowingly save the top assembly without thinking that if they have write access to the sub-assembly then it will also be saved.

Herein lies the likely source of your problem having a sub-assembly gives you the ability to manipulate the data in the context of reference sets so that you can see the effects. In order to be faithful to the changes that you make, where write access permits, NX will save the changes you made to the sub-assembly, so that the reference of the component used by the reference set of the sub-assembly can easily be other than you may logically expect. The person who worked with it before you probably thought to make a temporary change while working with the data unknowing that it could mess up the reference sets.

Difficult to get your head around at first. Really easy to experiment with and demonstrate. Kind of annoying and troublesome to maintain properly, so many people seek to avoid the problem in various ways.

Cheers

Hudson

 

[SiW979]

Well I worked the problem out, but there is still a little bit that doesn't make sense. I've put a little PPS together to show what I was doing, what I worked out and on the last slided what doesn't quite make sense. So have a look if you want and any comments will be greatly appreciated.



Best regards

Simon (NX4.0.4.2 MP4 - TCEng 9.1.3.6.c)

http://www.jcb.com

Life shouldn't be measured by the number of breaths you take, but rather how many times it's taken away...

 

[hudson888]

Simon,

That is a wonderful presentation, and true to form it shows a problem that I'm sure i have also seen occur. I have never seen anyone go to such trouble to describe it so well.

I suspect that as of NX-5 it may work slightly differently, just because the part templates seem differently set up, but it could be just how it presents and have no real effect.

I couldn't really reproduce what you're showing in the PowerPoint, but I recognise that it does happen under certain circumstances. I'm fairly sure I have seen the same occur in assemblies I have worked with in the past.

The best solution is probably as simple as manually adding the missing components into the SOLID reference set, although we'd all like an actual explanation as well.

Try looking at your Customer Defaults, under Assemblies>Site Standards the Model reference set is probably called SOLID in your case, but is "Add New Components Automatically" ticked on? I think you probably do.

If you make "Main System" or "Hydraulic System" the work part or displayed part how does it appear then? I suspect that once the reference sets of either of those is updated then the problem may go away. I can't be sure but I have always suspected that once you manually tinker with reference sets that some of the automatic updating that the system usually correctly assumes may not work properly.

Hopefully somebody will be able to shed a little more light that I've been able to as it can be puzzling. I'm sure all of this is based on simple operations that happen to be just a little awkward to describe.

Best Regards

Hudson

 

[CEGraves]

As far as I understand, if you make a part called Assembly Bracket and add components to it, no "Solid" reference set will be created. But, what you did was make Assembly Bracket the work part and added geometry to it per wave geometry linker, which in turn will create a "Solid" reference set. Once you made the filter bracket using those two circles, that filter bracket now has geometry in it, so a "Solid" reference set will also be made in it.

 

[hudson888]

Well spotted you're correct. That part is simple and I think fairly straightforward. Reproducing the behaviour whereby the components weren't part of the SOLID reference set is difficult to fathom, unless something is set wrong in the customer defaults, maybe perhaps.

If you have reproduced the second part of Simon's presentation then please let us know. I think it may be a manifestation with the three levels deep reference set of a reference set problem that I described earlier. Since I couldn't reproduce it I'm keen to guess.........

Cheers

Hudson

 

[SiW979]

Now here's the thing. I created a new part called FILTER-BRKT2 and I made sure that the part was completly empty. Basically I selected no geometry what-so-ever as a basis to create the file, therefore it is just a blank file, no geometry of any sort, zip. Look at the attached .jpg and you can see that there is already a reference set called solid.

So regardless of what method we use to create a new component, the system seems to be creating the solid reference set by default, coupled with the fact that I have set our customer defaults to add new components automatically, you would expect that any components that I then proceed to add would be included in the solid reference set automatically. I think this is a case for Mulder and Scully......

Best regards

Simon (NX4.0.4.2 MP4 - TCEng 9.1.3.6.c)

http://www.jcb.com

Life shouldn't be measured by the number of breaths you take, but rather how many times it's taken away...

 

[hudson888]

In your load options what is the default reference set set to?
Is it set to SOLID, and could that have something to do with it?

Regards

Hudson

 

[cmacca]

Or maybe your template file that you use to create the part has the SOLID ref set already set. Does both your assembly and part template files have the SOLID ref set created?

 

[hudson888]

None of the NX-5 out of the box templates appeared to have reference sets in them, but that doesn't mean somebody couldn't have created such a thing.