Dimension designations

[ptc-154724]

To anyone, I have relations added in a model, for an assembly, that control some of my dimensions. I went to go back into the relations and the dimensions are shown differently (but not all are changed) than I had input them, and want to know what the additional information refers to. Here is what I mean: Original relations: D4=CWTDBG D3=CWTDBG/2 Current relations: D4:1=CWTDBG D3:1=CWTDBG/2 So I am looking to find out what the :1 is referencing. Dennis
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[eric.mills]

Dennis Since this is an assembly relation, the : colon is for the component ID. You could have several parts in your assembly that have a d4, for example, this is how you separate them. Eric

[ptc-154724]

Eric, I thought it might be something like that. So if I wanted, I can use these type of designation if I want a dimension in an assembly be driven by a dimension in another assembly, correct? Dennis

[eric.mills]

Dennis All of the components must belong to some parent assembly and the parent assembly would have the relations. I will give a word of caution to you, making lots of links (relations) can give you lots of headaches down the road. You might end up with an assembly that will fail to open, worst case, or report other failures while opening or regenerating. This only gets worst when you use a PDM system, from the older Intralink series you might end up with a assembly that you cannot make a copy of. Pro-E has a lot of power to make these links or references, but those same references can cause grief down the road. As I pointed out this is just a caution warning. Best of luck Eric

[ptc-154724]

Eric, Thanks for the advice with the PDM system. We will be going to PDM Link over the next year and don't want any problems added to this. So would you say a skeleton part would be the better approach, to drive dimensions in a lower level assembly, from an upper level assembly? Dennis

[eric.mills]

Dennis The skeleton model is the best thing when trying to use the same references over several assemblies. Then if you change the skeleton the changes are reflected into the assemblies that use the skeleton. As I have worked on PTC PDM systems for many years I would say that they eliminate a lot of overhead on file management and can causes issues on parts that have lots of external links to them. I'm sure some people can give lots of examples of parts with links that work in Intralink/PDMlink, but the best advice I give is to limit your use of family tables and external referenced parts/assy. We don't purge our database so if an assembly uses a particular family table member and then the member is removed from the assembly at a later date, PDMlink will not allow us to delete the particular family table member from the table. We ended up just renaming the member to something we would never use again. Just one example on how the PDM system can work against you. Eric

[ptc-154724]

Eric, Thanks for the additional infomration. I was told that the skeletons do create alot of external references (have not used them here for that reason) and that this can be a problem as you cannot make changes to a part, unless the skeleton is modified. Our colleagues in Japan are staring out now using Pro/E and want to use skeletons, as the Pro/E Advanced Assembly training leads them to use skeletons, for a top-down design scenario. We also extensively use Family Tables for all of our parts/assemblies. We do not use nested family tables, but every part/assembly we make does, by our own internal standards, require a family table be created. So this we cannot help or get away from. If we find a part is no longer needed, we do not delete it from any family table, we just reference on the drawing it is now obsolete. Dennis

[DavidButz]

If you are looking at Skeletons, also look at using Layout, especially for Parameters and Relations.