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Top Down Design Referencing?


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<?:namespace prefix = o ns = "urn:schemas-microsoft-com:eek:ffice:eek:ffice" />
Gurus, I need a little help with referencing with Top Down Design. Well not just top down design, referencing in general.. I trying to go by what John Peng from PTC said in his TDD webcast. Basically what he did was

  1. <LI =Msonormal style="MARGIN: 0cm 0cm 0pt; mso-list: l0 level1 lfo1; tab-stops: list 36.0pt">create a layout, </LI>
    <LI =Msonormal style="MARGIN: 0cm 0cm 0pt; mso-list: l0 level1 lfo1; tab-stops: list 36.0pt">Create a top level assembly, </LI>
    <LI =Msonormal style="MARGIN: 0cm 0cm 0pt; mso-list: l0 level1 lfo1; tab-stops: list 36.0pt">Create sub-assembly


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So when you create a new part in Assembly mode first option;

1)copy from existing ;thats mind _if you want to create a new part you can copy the start parts WITH ALL IS ALREADY SAVED in this model part where you copy from

Ex if you have manny parameters and you don t want to re_create forevery new part choose''copy from existing''

In this case you must assembly manually you new part and you can start to create features in assemlly (insert feature)or part mode

2)locate deffault datum ;so your new part alreadyhave SYSTEM coordinate the same with the anssembly inside you build but if you must create the parameters or other information necesary you mast CREATE all manually but the part is already assembled FULLY constrain

3)you create a part completlt empty and you can must create everything including the datum plane and the feature can be attached everywhere

I use this option for example when i must have in the BOOM Ballons the components in statistics but this components is may be not a mechanical partsbut is created becuase i need information inside

4)create feature is simple;you can create a new component but all references are in assembly and for that kind of reason is not easy to modify in part mode but you can easy modify in assembly

I use this option for example when i must create the client building where your product are installed

More clear this part show the walls all arround uor machine to see yf you have all necessary space

One grame practice ismorethan tones of theory

Is may be difficult to fallow me but English is not my native language

If i can solve others problems mail me


Is usefull if you set model tree to have directly accesto the part like in picView attachment 681ture

Edited by: cristelino


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Thanks for the post, Cristelino, it has certainly helped.. you are very right, one grame of practice if better than a tonne of theory!

if anybody has any other suggertions, I would be only too hapy to hear them!




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Hi James<?:namespace prefix = o ns = "urn:schemas-microsoft-com:eek:ffice:eek:ffice" />

TDD is not aGospel and the way PTC is explaining it is only one way of doing it. My experience is that the approach depends much on the kind of project and particularly on the what I call "the master surfaces


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Pedja, Thanks for the concice explaination, I just have one question - what is and why do you place published geometry in the footer?

Thanks, again, if anybody has anything else to add, please feel free to!



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James<?:namespace prefix = o ns = "urn:schemas-microsoft-com:eek:ffice:eek:ffice" />

Usually I create one publish geometry per part (Ex PG_Housing_Top).Since the design changes all the time I have to redefine this PG by adding newly created entities to it(Ex later in design I may realize that I need to add few more surfaces).For this reason PG's should always be at the end of the model tree which footer automatically does without need to reorder it like in previous vesions


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I ahve createed a sup-level skeleton, using the published geometry from the top level skeleton.

if I want to assemblea part to this skeleton, it does not let me select the copy geometry, only the default datum planes..

why is this?