NX 4 Reference Set Uses

[jcbjon]

Hi all,

I am trying to do some restructuring work in NX4 and I have a large assembly that I am trying to break down. The idea is to have a file for each of the welded assemblies then a file for 'common parts' which has all ga components in (nuts, bolts, seals, trim etc) for specifying paint (as only the welded assembly components need painting. My question is, can I make a comon parts assembly that shows the welded assembly parts (for the purposes of positioning etc in the drawing files) where the welded assembly parts wont appear on a BOM.

I am aware this can be done using parasolids of the welded assemblies however I am trying to avoid that as they are a fixed item and wont update is the welded assembly files are revised. So, I was wondering if reference sets could do this task but I don't know the ins and outs of exactly what they are capable of.

Can anyone help - regards, Jon

 

[hudson888]

Jon,

If you want to make a what is commonly known as a weldment assembly where the commonest example might be taking various cut lengths of steel sections and welding them together them including a few nuts and bolts then I was surprised to find when I encountered it at a previous workplace that one of the best ways to to this is by using promotions. The act of promoting the parts removes them from the BOM and presents them in a way that allows you to unite then together to make a one piece solid assembly. I can't remember off hand all the pro's and con's of how this came to be the method of choice but it was the one selected of my colleagues for doing this sort of thing in some cases.

See if this works for you and get back to us if I have misinterpreted your needs

Best Regards

Hudson

 

[MSPBenson]

Do you wan't to do this in an automated parts list or in a TCeng BOM?

Hudson's idea is not a bad one but I'd advise using wave linker instead of Promotions. There's been rumblings that promotions were to be dropped in later releases of UG.
Not sure if JCB are still a little nervous of using live wavelinks though.

You can also try and play around with suppression of components.
When in the assy you DON'T want the components to be shown. Right click on the components in the Assy Navigator Tool (ANT) and click "suppression".
Pick this assy in the list on the left and then make "always suppressed".
The item will dissapear from the ANT.
If you need to view these parts after you can right click on the ANT (best place is the column headers at the top) and click "include suppressed components"
The part should be hidden in the GA but vissible in the WA.
Not sure how this reacts in Automated parts list or in the TCEng boms though. Give it a try and let us know.

Hope that helps.


Mark Benson
Aerodynamic Model Designer

 

[JohnRBaker]

Promotions are NOT going away. They will be supported into perpetuity.

And the fact is 'welded assemblies' are usually the most often sited example of where Promotions actually might be desirable OVER WAVE linked bodies.

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/

 

[jcbjon]

hi all

thanks for the replies - i had written out a lengthy reply to the first post but forgot to click post, however your input Mark is very interesting. You are correct regards wave linking. It is used but in conjunction with the TCEng software is can cause a number problems with updating (or at least I have found so far).

I have temp. got round my problem with parasolids, having parasolid models of the WA's inserted into the common parts GA to act as a visible reference, as they do not appear in either the automatically generated BOM or the TCEng generated BOMview... However I might have a play with suppression as using parasolids is becoming frowned upon as it is realistically a bodge and our CAD training department are trying to bring all our CAD perfectly inline across the company, so don't want to upset them!

I will let you know how I get on.. but its on the back burner as a more pressing pile of work just arrived on my desk... woot!

Jon

 

[hudson888]

Jon,

You'll find that you can wave link to components outside of the assembly so that the parent parts are removable from the assembly. Now when I first found out that my colleagues had the culture of using promotions rather than wave links I was surprised. Indeed there are those who manage by careful management of wave links to apparently exclude the wave linked components from their assemblies. This is usually important because the nature of the design flows such that you really do want those components in your assemblies even if you do need to exclude them from the parts list. It is really a problem of reflecting the organization's attitude to their product structure such that they allocate no additional assembly number to the weldment as distinct from the weldment with fasteners. Since this is a typical fabrication scenario, (along with similar cases for machined castings), I have always thought that promotions do a good job of filling that requirement.

To the general forum,

Historically we had promotions before there were wave links, so the functionality somewhat duplicates itself. I suspect that it might be a good idea to see the functions combined one day so that people aren't conflicted about which to use. In terms of the dialog a simple include or exclude from the part list toggle would suffice to provide the choice between how the assembly is managed. If I'm correct the only difference discernible to the user between promotions and wave-linked bodies would be this parts list related behavior.

Also for your consideration down the track there many or may not be issues if you use Vis-View or JT2GO to view and/or markup your assemblies. Presently however we have had issues especially in teamcenter managing the visualization .JT file data so that what occurs for NX is equally the case in vis-view. This is not something I have yet been able to test in NX-5 and whatever the answer I would like to also know whether the JT2GO and full product support it differently.

Also I want to extend that discussion if I may to include the effect of suppression the exported files for these JT2GO/Vis-View products. Given a few best practices I would be keen to set it up for some of my projects and test the best way to do so. I am most desirous of better ways to collaborate with colleagues and partners whose computer let alone CAD skills are at the low end of the scale, but who have great engineering and design input to be drawn upon.

Best Regards

Hudson

P.S. When I post here I try to use the right names for all the products, NX instead of UG, and Teamcenter in general has long since replace IMAN etc... Any clarification or correction of the JT2GO cum Vis-View product names would be welcome. If we can post it to a FAQ page and keep it up to date even better.

 

[SiW979]

Jon

Which divison are you working for at JCB? How come you have not used the CADET team or myself for information on this?

Simon Wright

JCB Group CAD Trainer

 

[ewh]

You're in trouble now!

Believe it if you need it or leave it if you dare. - [small]Robert Hunter[/small]

 

[hudson888]

Simon,

I'd prefer if you could share with us which method you would advise?

Best Regards

Hudson

 

[SiW979]

Hudson

We have various processes that we use, but until Jon calls me and gives me a bit more clarity on what he is trying to do, then I'm not entirely sure what to suggest. If he just wants to add the WA's for referencec purposes only, the he would need to add the WA then in the ANT select the WA > properties and click on component is reference only, when he then saves the GA, and opens it in his PSE (Product Structure Editor) in TCEng, the WA will not show as part of the BOM.

We would use WAVE linking for post welding machine ops, ultimately what we want is 2 seperate part numbers, one for the WA and then a separate number for the Machined WA. the reason beinng is that we do not always make our own fabrications in house, but we may choose to do the machining in house. In this case, we could sub-contract the WA out to an external company or our Indian fabrication divsion, this would then be shipped in to us and we would machine it here on one of our UK business units. It allows us to choose how we do business.

The same goes for castings, we want 2 seprate part numbers, one for the as cast part and one for the machined part, we have a number of small divisions who do not machine their own castings and some big divisions who do, wave linking with 2 seperate part numbers allows us to do this very effectively and allows our purchasing/procurement people to choose the way we buy our parts.
The next step is variant configuration, like paint for example, at the moment we have divisions who have multiple part numbers for the same component because it is painted in a number of difference colours (military green, construction yellow, arctic white ets) so when the need to change a hole size for example, they have to modify a number of part files and drawings when ultimately there should be just one componet/part/drawing and the colour shold be a pickable option in the sales codes.

Another example is different countries, we will have 15 different part numbers for assemblies that contain exactly the same components except that each assembly has a different warning lable in it written in a language to suit each country. Need to add a new part? well you've got to add it to 15 different assemblies, variant configutation will allow us to have 1 assembly with all 15 different decals in it. When a machine is ordered in Germany, variant configuration will flag up which decal is needed.

 

[hudson888]

Simon,

Thanks for your response. It all makes sense and I can see where you're going with this. In all honesty I get the feeling that there is some tension that Jon (I hope for his sake not his real name) may be bucking against the system somewhat and you know the system inside out and have rationalized how things fit together pretty well. It is in fact the very power of teamcenter that creates these sorts of problems. I have experienced this elsewhere and really it needs to be said that there is an element of trying to be all things to all people that causes purchasing concerns to intrude upon the engineering process. Not that that is necessarily a negative intrusion or one that can be avoided, since the purchasing department often have valid needs to be met. However engineers don't really give a rats hind end what color the thing is and that sort of detail should rightfully be dealt with by a clerical function otherwise you'll just wind up with a bunch of very frustrated engineers looking for a loophole in the system to make their life more bearable.

Anyway your description of how you use wave links was okay by me. The reasoning behind how and why you do things was clear and it was good of you to take the time to explain it for Jon's sake at least, as I believe you earlier comments may have set him back somewhat. For what it is worth it shows both initiative and motivation to both find the forum and use it to explore alternatives seeking understanding and knowledge shouldn't be viewed as dissenting so much as trying to learn. That's why I'm happy you posted back as I think there is something learned from your explanation.

I get that you're pretty clued up on the technology from the way that you write, so tell me were it not for the way your part numbers work, would you have a technical problem with using promotions in Teamcenter? In other words does the chicken come before the egg, or should other readers who are thinking of using promotions, given that their part numbering system permits, still be concerned to avoid doing so as you or others may have found problems managing them via teamcenter? I'm asking for my own benefit apart from anything else, experimenting in teamcenter as I would like to do has its drawbacks in that you can't easily just delete what you've done and start over as easily as you might in the Native system. Your point that Jon should have asked surely was for just those sort of reasons.

Best regards

Hudson

 

[SiW979]

Hudson

I have very little experience with promotions, I learn't WAVE and have always used it. I believe though there a couple of reasons that we have it in our CAD standard that promotions should not be used and this reason was based on our old hardware architecture. Our company (JCB) has the world headquaters which, was where our central server was kept and all the CAD data for our other UK divsions in various locations around the UK. Come Monday morning when there were 60 engineers all trying to load up master assemblies, we would wait for 3-4 hours for the assembly to load on the old unix systems. Even with low volume network traffic opening a large WA like a chassis would take many minutes and it is this reason we don't like promotions as I believe (I could be wrong but this is what those who used them told me), in order to view a promoted body, you had to have the parent assembly open as well. As you know you do not have to do this with a WAVE linked body.
Now we have site specific servers and central hub for released parts and TCEng data shares. We are on 64bit windows systems (big mistake) with 8GB of memory, even the biggest assemblies will open in a few minutes so time is no longer an issue, but the part numbering and way we drive our PSE is, and WAVE is a fantastic tool for achieving what we want. So in answer to your question no, if the way your company does business doesn't rely on part numbers like ours does, then promoted bodies might just be thing for you.
I also fully agree with your commments about engineers work loads, each passing month sees engineers being forced to more work to make down stream peoples work easier, we are implementing SAP at the moment and it is a nightmare, especially with lagacy data that we are now need convert to UOM (Unit Of Measure)items (massive amount of work) and the fact that it can't handle - (minus) quantities (return to stock)that we used to use on the old BULL Mainframe system.

I didn't mean to sound so abrupt when replying to Jon, it's just we have a set proceedure for these sort of issues. Each of our 21 divisions has at least 1 CADET (CAD Evolution Team) representative who are (meant to be) NX super users, that is the first port of call. If they can't help, a call is raised to the entire CADET team calling on the collective knowledge of all, if they can't help, then it comes to me and I escalate the call to Siemens and use this forum.

I don't have a problem with the users at JCB using this, forum, after all, I sent the link out via email, but only once all other avenues are exhausted, especially when we already have proceedures and SOP's in place. After all I'm aiming to standardize working pratices accross the group not contaminate them further than they are already.

In case your intersted I have attached one of our WAVE linking step by step instructions/presentations to this message.

Regards

Simon

 

[hudson888]

Simon,

I don't know if you wanted/expected feedback on your info but I thought I pass on some comments anyway.

Thanks for all the info. Sounds like you have a pretty good well thought out system, and your procedure is thoroughly explained. Not all places have this level of diligence on the organizational side, and even when they do they can still get it wrong. There are a lot of methods out there not all of them good, and varying opinions will be expressed about the rights and wrongs of wave linking. As always I'm keen to have the conversation about what works best, if anything procedures can tell you how to do things but seldom explain why you should do them a certain way. Like anything you can do it well and badly if you try.

We have worked similarly with left and right handed parts, as you show them it appears that they reside under the component that they are linked to, but set to reference only according to your procedure. Whereas we didn't set them to reference in NX-3, just removed them from any reference sets and placed them on a separate layer. I wonder do you use Teamcenter Visualization or JT2GO, saving .JT files of your assemblies for non-CAD users and reviews etc. We do and found that there were reportedly complaints that the lower level parent parts of the wave links showed up in the tree during some of the reviews. I guess somebody was doing something wrong, but the supposed fix for this has been to save a separate assembly just to do all the wave linking in. Another dumbing down of a perfectly good system to burden engineers with what could probably have been avoided. I wonder if the setting to reference can work better for the .JT files creation, and perhaps even operate in the absence of reference sets in your assemblies.

There is a separate debate to be had over the use of reference sets in assemblies. I'm keen to know what you do, in practice it can create some confusion where assemblies are three levels or more deep, with the reference set in the reference set problem. Means to maintain this mat have to be instituted, and new users are frequently confused by it.

Now with how and where you place the datum planes for wave linked mirroring, there is a theory that you can do it anywhere that you like, and you can wave link at any level of the tree. Usually this gives the appearance of working for a while, but may become unmaintainable if things go wrong or the links become broken. In NX-5 under teamcenter 10 the links are getting broken every time files are brought in and out from Native to work offsite. You can do things more carefully if you're well informed to avoid all this, but you could mount a good argument that you really do need to be too careful and too well informed in order to undertake certain activities with any degree of safety.

The trick with whatever you do is to make sure that you can easily remove the components and wave links from you files and reliably put them back in place and re-link or recreate the links that you may need to start again from scratch. Sometimes things go wrong, and your best remedy will approach starting again. Nobody likes to hear it and it is no fun, but experience with teamcenter has taught us to be cautious with wave links.

Promotions would be unlikely to be any less onerous in terms of managing your data, and you can't do a mirrored promotion. All they do is to make the body from a component of an assembly available at the higher level so that you can perform some additional operations on it to show post machining. Then if you create a parts list it will be added with no additional duplication of reference data to manage and you can item number the machined component with no problems. It is ideal where you want to add holes drilled on assembly, sometimes the odd line bored hole or some people may use it to add chamfers onto welded edges etc. A lot of this occurs with welded assemblies where the machining takes place after the welding so each of the parts used in the weldment has a its own part number drawn individually as delivered while the weldment itself is given a part number drawn as an assembly and promotions applied where post machining is necessary. Some organizations would express the welment pre-machining and post-machining as two different part numbers but in general engineering this is usually not the case.

At least in native it you would open the machined weldment to see the promotions, when you view the component using make displayed part, then the machining will be absent. I really don't think that they place an extraordinary burden on the system. I think your advisers were probably ill informed or relied on experience from a very long time ago having never revisited promotions to check. As I say NX-3 and up I can attest that they have their albeit limited use but perform that function with no know problems or defects in Native.

You need to enable promotions in your customer defaults in order to have them available. They are usually switched off as NX is delivered.

I have historically come from a Unix background, post DEC and even the old GE systems, and recall the slowdowns with assemblies in the past. If you hark back to the early introduction of assemblies say versions 10 and 11 of UG, then there were other reasons. Otherwise unless you have only recently adopted faceted representations and/or partial loading then the improvement is mainly down to perhaps some improvements in the software, and certainly the later hardware is better performed.

Thanks again for your replies

Best Regards

Hudson

 

[jcbjon]

My my, thats alot of information from everyone! Sorry it's been an awfully long time since I posted a reply as I have been working on a different project that was more pressing.

Thanks Simon for that post, thats exactly what I wanted to do, make it a reference part and so it only appears in the CAD and not in the PSE or the BOM, except you you made it about 100X less complicated than what I was thinking! <-- This is why he is a CADET member and im not! haha

I would have asked you guys directly but it wasn't a pressing matter so I thought I would see what variety of ideas there were on the matter on here... which seems to have opened a pandoras box of information! I am however aware there are a number of set procedures and methods I use I run past out CADET user here (Lee Milward), just thought I would try the forum.

Thanks again Simon, and everyone else as well, seems to be working spot on! :-D