27 Replies Latest reply on Aug 19, 2015 5:09 PM by Tom Helsley

    Where to store custom properties, drawings or models?

    James Howard

      Where do you put your variables?  The vast majority of my parts have a single drawing, the drawing# and model# are the same.  In the middle of setting up an EPDM workflow to automatically update the revision info (rev, description, date, approval), I find myself very confused as to the correct path to take.  I can store all of the rev information in configuration specific custom properties in the model, then link them on the drawing, but then the drawing doesn't update those fields in preview/edrawings until I checkout, open, and checkin the drawing.  I can store the rev information in just the drawing file, but then it isn't linked to the model and doesn't show up in BOMs.

       

      Currently I've got everything set up as such:

       

      Drawing and part advance together through the workflow

      Model holds config specific properties (materials, process, weight, envelope, PartNo, description, etc)

      Model holds rev information that gets updated through the workflow

      Drawing ALSO holds the same rev information that gets updated through the workflow, but pulls desctiption, PartNo (used as drawing number), weight, process, materials form the config specific properties in the model.

       

      I don't usually like putting data in two locations for fear of only one location being updated.  Is there a better way to store the variable data?  Am I making a mistake in treating drawings and modles as a single entity in the workflows?  I can take this implementation in any direction I want, just need some tips/guidance/best practices. Does anyone have any sample templates, workflows, and data cards they could share, or links to any good resources?

        • Re: Where to store custom properties, drawings or models?
          Faur Arama

          James,

          You don't have to put variables like material, weight, description and so on also in drawings. These properties ca be placed in drawings from models. Using prpsheet these variable values can populate a title block. Also in PDM you can define variables if you want using $prp and $prpsheet. In admin guide in variable chapter look to variable mapping.

            • Re: Where to store custom properties, drawings or models?
              James Howard

              That's what I'm doing for the part properties, but what about revision variables?  I'm using

               

              Revision, ApprovedBy, ApprovedOn

              Rev01, Rev02, Rev03, Rev04

              RevApproved01... RevApproved04

              RevDate01... RevDate04

              RevDesc01... RevDesc04

               

              so that I can force the revision table to be filled out during workflow transitions.  Where should those variables be stored?

                • Re: Where to store custom properties, drawings or models?
                  Brian Dalton

                  For most values, I place them in the model and link them to the drawing, the exceptions being DrawnBy, DrawnDate, etc... because these values refer specifically to the drawing and are not relevant to the model.

                   

                  For the Revision variable, I put it in both the model and the drawing.  This is because each file has its own revision counter in PDM, and each file is 'stamped' with its own revision letter, so it's logical that each have its own variable value.  In our system, the model and the drawing are always revised together and will always show the same revision letter, but because of using a separate variable for model and drawing, we could change to a system wherein the drawing and the model were allowed to be revd individually and we would not need to change our underlying mechanisms.

                    • Re: Where to store custom properties, drawings or models?
                      James Howard

                      Ok, that's on par with what I have set up currently.  Have you had any issues with parts getting out of sync re the rev letter, or does a robust workflow prevent that situation?

                        • Re: Where to store custom properties, drawings or models?
                          Brian Dalton

                          Workflow, Baby, workflow!  Try to set up the conditions and permissions to be as bullet-proof as possible so as to avoid the files getting out of sync.  Even then, diligence is required.

                           

                          I have developed the habit of 'religiously' putting detailed comments in for transitions to aid in tracking after the fact.  If things get messed up, and files are transitioned (or not transtitioned) when they shouldn't have been, the comments can help you find errant files and roll them back.

                           

                          Such comments have saved my EPDM Admin bacon several times...

                            • Re: Where to store custom properties, drawings or models?
                              James Howard

                              What about models with multiple configurations that each represent a different part number? Seems like the EPDM revision is linked just to the file, and bills of material in EPDM don't show the Revision variable value in either the file or the date card, but only the EPDM revision value.  I may have three drawings, each with their own number and revision, that reference three configurations of one model file.  Is this just bad practice, or is there a better way to manage these parts?

                                • Re: Where to store custom properties, drawings or models?
                                  Brian Dalton

                                  I would consider that bad practice just from the standpoint that it's complicated, confusing and not necessary.  We stick to the simple convention that one file = one part/assy.  Much easier to live with that, IMHO.

                                  • Re: Where to store custom properties, drawings or models?
                                    Tom Helsley

                                    My company also has specific part numbers in the configurations, but we control the revision at the document level (general properties), not the configuration level.  As a result, all part numbers in the file are always at the same revision level whether they changed or not.  But we also use only one drawing file for all the parts.  So basically, think of the model file as a drawing number, and the part numbers are the drawing number plus some dash number(s).  The model and drawing documents are the controlling specification, and the configurations in the model file are the specific part numbers in the family of parts.  It works very well this way.

                                     

                                    Having multiple drawings to show different configurations of one model, and having different revisions for each configuration / drawing IS a bad practice - especially for PDM. 

                                     

                                    You could still independently revision the model and drawing file, but the revision for the model file controls the revsion for all of the configurations within it.  Of course this complicates things as to what the manufacturing revision is, and how you manage that.

                                     

                                    That's my 2 cents.

                                      • Re: Where to store custom properties, drawings or models?
                                        James Howard

                                        I treat tabled drawings that way as well, where the revision on all configs and on the one drawing get updated to the same level.  I've been trying to stay away from that, however.  While it cuts down on drafting time to use the tabled drawings, we put the rev on marked parts, in the MRP and accounting systems, on the work orders, on kanban bins, etc, so changing a rev on parts unnecessarily means a lot of extra work down the line where it's easy for non-engineering personnel to make mistakes.  For castings it would mean tool modifications to update the rev letter for table drawn parts that didn't actually change, which is money.  Using FFF rule for revisions means we needn't always track the rev letter down to the bin, but we want to know exactly what revision of the part went into an assembly when it was shipped.

                                        • Re: Where to store custom properties, drawings or models?
                                          Brian McEwen

                                          One part number per model is fine for most of our stuff (but we have some we may need to fix by splitting up).  I guess common parts can be in a common sub assembly instead of a config. 

                                           

                                          But what about a homemade toolbox?   Do you have a different solidworks file for every  length of 1/4-20 socket head? Each length has a different part number... ah but it doesn't change revisions.  Is that where an exception is okay?

                                          (working on new EPDM implementation...)

                                            • Re: Where to store custom properties, drawings or models?
                                              James Howard

                                              Brian,

                                               

                                              I have a a custom toolbox where I have all hex nuts (or all M12 socsets, or all o-rings, etc) as a configs in the same file.  For commercial parts like that, I have a "Non-Rev" workflow state where everyone knows that we don't care about and don't track revisions, but still check-in/out the files to add sizes.

                                               

                                              I never use configs to denote different part numbers for production parts, even if the parts are nearly identical.  Sure, it's easier to model wiper rings that are exactly the same dimensions except the outer diamter as configurations, but once they're modeled you'll save tons of time later if you split those into separate files.  My rule now is that when making a change to one configuration of a part, all configs get their revs incremented.  If the configuration revisions need to be split up, then they shouldn't be in the same file.  The only reason I'm using configs on production parts is to show them without edge fillets, to show the same spring at different heights, or to show end caps with different NPT port sizes because they all share one single drawing.  Derived parts can also be a good friend when configurations can't be.

                                               

                                              I have used the "common subassembly" route on a few things.  I'm not yet convinced on the value of that technique, but it hasn't caused any problems either.  I only use them as non-revisioned assembies so more "configurations" can be added at will, and I don't display the subs in any BOMs.

                                              • Re: Where to store custom properties, drawings or models?
                                                Tom Helsley

                                                I don't recommend having a separate file for each size of a part, whether it is a 'homemade' toolbox part or not.  You can store the individual part number information in the configurations.  The benefit of having all the different sizes in the configurations of one file is ease of changing sizes. 

                                                 

                                                If the different sizes were in different files, then you have to use the "replace component" command, browse for the component to replace, fix the broken mates for the assembly's active configuration, then do the same for the other configurations.  The mates usually fall apart when the replaced component wasn't made from the same file as the first one (the underlying geometry names aren't the same).

                                                 

                                                But, if all the sizes are in one file, all you have to do is RMB on the component, select component properties, pick the configuration that represents the size you want, pick the assembly configs you want to apply that change to, then click "OK".  There is no browsing for another component, and there are no mates to fix.

                                                 

                                                One last thing.  Managing revisions with configurations is a very bad idea.  I've seen all kinds of problems pop up because of this.  PDM systems don't use configurations for revisions, they just make a copy of the file instead.  So, with that said, I manage the revision property in a file in the general properties only, not each configuration.

                                                • Re: Where to store custom properties, drawings or models?
                                                  Tom Helsley

                                                  Oh, and I also don't manage revisions for library (COTS) parts.  In EPDM, as others have mentioned already, the library parts are in a separate workflow that doesn't roll the revisions.  We just check out a file, add a config (size), then check it back in.  I haven't yet tested how EPDM handles toolbox parts.

                                                    • Re: Where to store custom properties, drawings or models?
                                                      James Howard

                                                      Tom,

                                                       

                                                      This revision issue is the main reason why different sizes (of rev controlled components) should NOT be kept as configurations.  You are correct that replacing components breaks the mates, but there's a simple solution to that: never make a new size from scratch.  If you always "Save As" and then modify dimensions, the geometry always has the same names.  I've found the pain of replacing components (which is actually easier to do in EPDM with 'update references') is far less than the pain of change management caused by being forced to update revisions on every configuration simultaneously (which means for EVERY part, my drawings have to be updated to show the new rev, my accounting and purchasing systems have to updated to show the new rev, etc down the line).

                                                        • Re: Where to store custom properties, drawings or models?
                                                          Brian McEwen

                                                          James and Tom I think you guys agree, if I correctly interpret the full intent of your statements.

                                                           

                                                          Summary of the conclusions:

                                                          1) In most cases keep different part numbers in different files.

                                                          1b) If you do make an exception then every config (part number) in a file should have the same rev level.  ""If the configuration revisions need to be split up, then they shouldn't be in the same file."" [James Howard]

                                                          2) Toolbox/Library parts it is okay to combine PN in one file using config because they don't have drawings and they don't get EC controlled revisions.

                                                           

                                                          ""I don't recommend having a separate file for each size of a part"" [Tom Helsey] I think he was referring here to only Libary and Toolbox type parts. He also says not to have separate revision levels in one file.

                                                           

                                                          Thanks!

                                          • Re: Where to store custom properties, drawings or models?
                                            Faur Arama

                                            As Brian said you must have a rule about how drawings and models are revised. When we make a revision we make transition for both types of files, even there cases when the modifications are made only to one type.

                                            Unfortunately as far as I know there no links between revision table and PDM revisions. User must make modifications in rev. table by hand. If you respect this rule you don't have any sync issues about rev.

                                        • Re: Where to store custom properties, drawings or models?
                                          Lee CS Young

                                          James Howard wrote:

                                           

                                          ...but then the drawing doesn't update those fields in preview/edrawings until I checkout, open, and checkin the drawing.

                                          If you update the revision variable before you do your changes you won't have this problem.