Use of Model Reference set in assemblies

[DMiller01]

I was searching the forum for info on lightweight reference sets and I came across something posted by John Baker that I hope to get some clarification on. John's quote follows:


"As for Reference Sets, Load Options should be set to Model. If you've created your Sub-Assemblies correctly, that is that they do NOT have a Model Reference Set defined in the Assembly file itself, then they will automatically be loaded as Entire Part as they should be."

My question is: why should an assembly not have a model reference set? Our template part which we use for our new part creation includes a model reference set so all our new files automatically have one too. When one of these new part files are used for an assembly, should I then delete the model reference set? Should I be using a different template file for new assemblies? And why should I want he entire part reference set loaded for assemblies, especially when I am trying to minimize what I am loading?

Thanks,

I am using 7.5.2.5 NATIVE on Dell with windows XP OS

 

[ewh]

If the assembly is set up correctly, it should only contain its constituent components, thus "Entire Part" would be correct.
Using different reference sets in assemblies usually causes problems down the road. It is much better to use configurations in assemblies than to try to control them with reference sets.
As to whether leaving a "Model" reference set in the file, it probably won't make much difference (as long as it contains the same entities as "Entire Part").

"Good to know you got shoes to wear when you find the floor." - [small]Robert Hunter[/small]

 

[JohnRBaker]

If you leave the Customer Defaults in their out-of-the-box settings as to how Reference Sets are named and what they should contain, then you will have NO problems since your Assembly files will NOT have a 'Model' Reference Set created in them in the first place. Now if you've created them manually in your 'Template' files then that was a waste of time as the system, when left to itself, will AUTOMATICALLY create a 'Model' Reference Set only when it's appropriate, which is NOT when the only thing in your Assembly files are Components.

As for the 'reason why', Reference Sets act as a 'filter' which will not allow you to see anything that has been filtered out. So for an example, if you create an Assembly and you create a 'Model' Reference Set in that Assembly file and you add all of your Components to the 'Model' Reference Set and you never opened that assembly again, that wouldn't be a problem. But what if you later on went in and added an additional Component to your assembly and you forgot to explicitly ADD it to the 'Model' Reference Set it will never be seen wherever the Assembly file is used as a sub-assembly and there will be NO way of knowing that extra Component is there unless you go and look in the Assembly File itself. Now to make things even worse, if one of those Components in your Assembly file was an Assembly itself and even if you never actually changed the Assembly file with the 'Model' Reference Set in it but rather you added a component to that lower level assembly and saved it you would still be in trouble at the top level since that 'Model' Reference Set would still NOT recognize that lower level change since it was ALSO 'filtered-out' by the higher-lever Reference Set.

Trust me, this is something that if you can avoid it and if the way the system works out-of-the-box gives you what you need I WOULD NOT MESS WITH IT. If you do, you will come to regret that decision, and it will probably be at a point where it will very expensive to go back an 'undo' the situation, and them probably only after something happened where Components got missed and never made it into your final product model which could prove very costly if not discovered quickly before something was being assembled on the shop floor.

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

http://www.siemens.com/plm

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