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Improve the Compare to CAD Tool in PDMLink

Improve the Compare to CAD Tool in PDMLink

If you ever have used or plan to use the "Compare to CAD Structure" tool found under a wt-parts Structure Tab: this is for you.

Please read and think about how the current functionality of this tool affects you.


I have up until now assumed that this tool compares a wt-part structure with its owner-linked CAD structure, the "Initial Values Selection" led me to believe this (notice that both the wt-part and CAD assembly are identified down to their version):


But when you investigate the CAD structure that is being compared, you may not recognize it...

The reason for this is that you are not looking at the CAD-structure specified in the window above but a calculation of it based on the wt-part structure and the owner-links in it.

This is causing our Creo users a lot of confusion and frustration since they are the ones responsible for both Creo CAD and wt-part structures, here is a simple example:

Sometimes the Creo CAD parts in our Creo assemblies are not the "original" valid for production, merely a "rough" approximation of its geometry to have as a representation in the Creo assembly.

We name them *_spec.prt in order to single them out. Those are then Image-linked to the corresponding wt-part so that the wt-part structure is built correctly. When the user then compares the wt-part structure to the CAD-structure he will find this (comparison window to the left and Creo-made assembly structure to the right):


Well, there you have it.

All Product Ideas should end with an idea, so here is mine: Make the Compare Tool actually compare the objects it says it compares. Please vote up.


Hi Alexander

Your screen shot is the normal behaviour.  As it will show the "owner" CAD.  

The Wtpart to CAD compare is not only a compare tool.  but also an update tool (reverse build a BOM change to the CAD structure) .  So in that use case, you will see added or removed CAD that are not yet assembled (or removed)

The image link is a particular use case. And I'm agree , the understanding  can be confusing. but the result is right once we have undersand the difference between owner and image link (wich should just represent a different representation of the same "stocked" part )

There's no difference icon, and your BOM is fully Built and up to date

We have this use case, and explain to our CAD user to mainly use the CAD to Part comparator, and /or to display the "related CAD" tab in the comparator, to always see the "secondary" CAD linked to the Wtpart


5-Regular Member

Hi Gregory

Thanks for replying, it is good to see that I at least have one shoulder to cry on

After having spent over an hour on the phone with a PTC Product Manager regarding this yesterday, I know that this is "normal behavior" and "working according to spec", and it may be so. But in my opinion the tools function is incorrectly presented to the user: if the Creo built assembly structure isn't taken into consideration in the "comparison", why mention it at all and why call it a comparison tool?

If the tool is called "Compare to CAD structure" and it even displays the linked assembly version as the one being compared it should do just that and nothing else. Wouldn't you agree that this would make the system more user friendly?

Maybe the tool should be divided into a strict comparison tool (compare this Part object version to that assembly object version) and another tool for manipulating/calculating/whatnot different structures (I leave the naming of that tool for others, as long as it doesn't include the word "compare"...)

For the time being we will have to instruct our users to avoid the "Compare to CAD structure" from the Part and instead use the "Compare to Part structure" from the assembly (although I couldn't get a clear answer from the PM if the Part structure "compared" in this tool was the actual Part structure or "calculated" from the CAD assembly structure...)

Community Manager
Status changed to: Archived


We are archiving your idea as part of a general review. This action is based on the age of your idea and the total number of votes received, as per this announcement.

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