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GO_1089897812-Amethyst
12-Amethyst
May 2, 2024
Question

Change Origin - 0-0 position - after placing - Ordinate Dims?

  • May 2, 2024
  • 4 replies
  • 5273 views

Hello. I posted this question on Eng-Tips and thought I'd come here.

 

I just started using CREO (started at 7 we just upgraded to 10) and there is something that's been bugging me about how CREO manages Ordinate Dims.

 

So, I've used NX and SolidWorks in the past. In both those programs I could start an ordinate chain by selection 0-0 and place Dim chains. In both those programs - if later on you need to change the 0-0 (origin) you would edit one or both 0-0 Dims - select a new reference and all of the dims updated. When I first started using CREO 7 I thought this would be a thing. Apparently, it was not. My colleagues even warned me if your 0-0 loses its reference (due to surfaces/design changing) you had to trick the origin into finding itself again. I performed a search - and I believe this has been going on within CREO since maybe 3.0. That seems crazy.

 

So, leapfrogging to CREO 10 I was like - this definitely got fixed right? Well, I sense that this still isn't an option. How can this be? This is CAD 101 - allow for modification/changes to increase productivity and address any errors you find while using tools that have been provided you.

Does anyone know how to reassign 0-0 after initial placement? How to fix a dangling 0-0 if surfaces change? And please don't forward me to the - "Change the first know ordinate dim to linear - then force back to ordinate and hope it works" That is kludgey.

 

I am surprised this isn't a thing in 2024 - CREO 10.

    4 replies

    G
    GO_1089897812-AmethystAuthor
    12-Amethyst
    May 2, 2024

    This is what I refer to for the Kludgey fix to remind users (again this was 2015 and it's still a thing):

     

    Solved: Ordinate Dimension Reference - PTC Community

    K
    Kotom-Eng16-Pearl
    16-Pearl
    May 2, 2024

    You are in the wrong forum.

     

    PTC has two CAD systems:    Creo+ and Creo Parametric    and     Creo Elements Direct.

     

    Which makes it confusing.

     

    More, for Creo Elements Direct:

    - The 3D software name is Modeling, and

    - The 2D software name is Drafting.

     

    For Creo+ and Creo Parametric, use only this tab:

    KotomEng_0-1714653726065.png

     

     

    You should move your post to this community to have a better chance to get an answer.

     

     

     
    S
    23-Emerald III
    StephenW23-Emerald III
    23-Emerald III
    May 2, 2024

    I'm thinking you are going to be disappointed in the answer. You can used edit attachment and that does sometimes work. Sometimes it doesn't. 

    I've never tried to specifically change the origin.  My quick check doesn't give me any confidence it's possible.

    Creo drawings will cause you to go insane at times.

     

    If the ordinate dimension was originally created as a linear dimension and you can figure out which dimension was the first, on occasion you can switch it back to linear, fix the reference, then switch it back...I think it worked for me once, usually it doesn't. I gave up years ago. If I have a failed origin, it's just faster to re-create the dimensions than it is to try to hack a solution.

     

    Maybe someone else has a better answer...hopefully.

      G
      GO_1089897812-AmethystAuthor
      12-Amethyst
      May 2, 2024

      So, I had someone on Eng-tips state that once he places his dims the design never changes so why do you need to redefine. Regardless of why - it should be a thing - especially in 2024. So, we do drawings as prototype and do a prototype release - but through test/validation things do change. I haven't tried this - but if the 0-0 origin face changes in anyway the reference is lost in the drawing. To solve this issue you have perform that mess a kludge posted in my second post. Now if the first ordinate reference for any reason is removed (and yes this does happen in a dynamic change environment) you can never recover the ordinate chain. Everything is lost. Again, this shouldn't be an issue in 2024. Hey sometimes a user makes a mistake - places 30 ordinate dim in a chain - and then realizes he selected a wrong 0-0 reference, or maybe a directive comes down to use a different face for 0-0. Currently you have to start all over.

       

      Please PTC add this to CREO. Simple request: Click on 0-0 (one or both) - click redefine - assign new reference - and all dims refresh. Why do this - because things change - references are lost - it is a simple and elegant way to resolve conflicts.

        S
        23-Emerald III
        StephenW23-Emerald III
        23-Emerald III
        May 2, 2024

        @GO_10898978 

        Just so you don't feel all alone...this product improvement request, also from 2015 has 100 votes (aka kudo) (i'm also sure there was old school enhancement request way before that system was made). Feel free to add your vote.

        Maybe it'll be the 101 vote that will get product managers attention! 👀

        https://community.ptc.com/t5/Creo-Parametric-Ideas/fix-ordinate-baseline-missing-reference-and-allow-change/idi-p/467510

         

        On a good note, I will say that the users were able to get PTC product managers attention last year and got action to some long requested improvements It was just a few improvements, but it was an effort by some dedicated users and also an effort by product managers to solve some of these long standing issues....one little ray of hope...🌥️...

         

        and with respect to never changing something after release...ya...right...i never NOT change stuff. (double negative intended)

        S
        StephenV12-Amethyst
        12-Amethyst
        May 2, 2024

        Try this: in your model put a datum plane where you want to start your baseline (0,0). Make that datum plane independent from model geometry (use base datum offset) if you change geometry and want baseline to stay where it’s at. If you want baseline to move with modified geometry, then adhere datum plane to the geometry surface by (datum, through, select surface) then the baseline (0,0) will stay with geometry.

        I tested this and it worked. I give credit to my coworker, like me, a Mechanical Designer, who provided this simplistic approach. We are in parametric land so ‘methodology” is key.

        I used MDB soft & hard ware = Manual Drafting Board, then stylus pens in IBM CADAM, Procadam, Computervision, CADDS V, Catia, Unigraphics, NX7-9, PTC (Pro-E, WF, Creo), SDRC, Autocad, Solid Edge and Solidworks. Each own(ed)(s) its own aggravations. Keep an open mind. Think methodically, but you can only best do that if you know the CAD system decently, so give it a chance.

        Granted PTC never the greatest detailer (ctrl+sel to get 2nd entity for a corner – about time that was fixed : ) …but gee a very powerhouse for engineering, calculations, humungous assemblies and more. Pioneering to MBD.



          G
          GO_1089897812-AmethystAuthor
          12-Amethyst
          May 3, 2024

          So, I will look at this. I will agree we do not implement MBD - or good modeling practices. We have fairly simple parts - not that complex. I have - in the past - always developed the model using dims - most likely not referenced to the correct A/B/C datum plane - and then use drafting to finalize all the details. I'm fine with this. When I model, I model to finalize part without spending too much focus on final drawing. I do believe this is a benefit that should be implemented in all CAD systems.

           

          I still think that CREO should allow for redefinition of all ordinate dims - especially 0-0. And if 0-0 or any other ordinate dim loses its refence - offer tools to reassign. Simple request. I was talking to my fellow colleagues - one mentioned if the first dim in the chain is removed (this does happen) there is no way to recover. Start all over.

           

          Oh as I was typing there was something else that bothers me - adding centerlines to holes within drafting. I was so frustrated when I first detailing with CREO - I found that you have to insert model items - see a million centerlines try to select the ones you want and then hit okay. I think there should be a tool with drafting to add these on an as needed basis - by the way I haven't tried this in CREO 10 - but I have a suspicion that this isn't a thing.

          tbraxton
          22-Sapphire II
          tbraxton22-Sapphire II
          22-Sapphire II
          May 3, 2024
          @GO_10898978 wrote:

          ... When I model, I model to finalize part without spending too much focus on final drawing. I do believe this is a benefit that should be implemented in all CAD systems. ...

           

          This approach is not consistent with the Creo parametric workflow paradigm. The drafting package is not best in class, and you would benefit from leveraging the modeling power to create the drawings from model defined data if you must create 2D prints.

           

          IME if I users are designing parts that are driving 2D prints it is well worth the effort to include the design intent and supporting dimensions in the 3D models (MBD or not). It will decrease cycle time to get both the model and drawings completed.

           

           

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