Section relations won't update

Ok, here's my problem. I created some relations in a section of a variable section sweep, and have some equations referencing parameters that were created in the part. When I change some of the part parameters, my section doesn't respond unless I open the relations editor, navigate to the section's relations and click the button to execute/verify relations. I go back to the regular part and do a regen and it works. What am I doing wrong?

Thanks in advance, Jason L

Reply to
Jason L ©
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Is you sayin' that if you change the parameters and regen the part the VSS section isn't reflecting the changes? Is there a ref dim value being included in the relations? (ref dims update post section regen)

(I have stumbled across similar situations, took two consecutive regens, etc. Not sure if it was I or Pro/E that was confused.)

Reply to
Jeff Howard

Jason, try taking the section relations out of the sketch and jus creating regular relations. This should resolve your problem

Glenn |B

Reply to
GWDavis28

I would, but the trajpar relation that references part parameters needs to be in the sketch or my wave washer won't have any waves to it. I am just trying to create the perfect crest-to-crest stacked wave washer that is available through Smalley Steel Ring Co., and I need it to be flexible in an assembly.

If anyone has any regular or crest-to-crest wave washer models that are easily made flexible, let me know, because I would like to compare models.

"GWDavis28" wrote in message news:u9udnZ_tyOB--tLeRVn snipped-for-privacy@giganews.com...

Reply to
Jason L ©

sorry Jeff, no ref dims used. I just can't figure it out.

Reply to
Jason L ©

Here is the link to my parts. Feel free to look at my relations and tell me what I am doing wrong.

formatting link

Reply to
Jason L ©

Hi Jason,

I've seen this before and my fix was just to Edit Def, Ok the VSS. After playin' with your file a bit I found a way to get the VSS to regen correctly:

In the VSS sketcher relations; Insert "amplitude = free_ht" above your sd7 assignment. Substitute "amplitude" for "free_ht" in your sd7 assignment.

The VSS will then update correctly when you change the part param FREE_HT and regen.

I have no idea why. Forcing a param read before section regen? Normal or bug? I've had no Pro/E training and never quite know when I'm (or anyone else is) doing something "right". I've never assigned D values in Part Relations (vs feature or section relations), for instance. Is that a common practice?

Reply to
Jeff Howard

Thanks so much Jeff for getting back to me so soon. I am going on vacation for a week, so I will have to try your fix when I get back. As far as your other questions, I am in the dark as much as you. I had very little Pro/E training a long time ago, so for the most part I am self-taught. We don't even have maintenance here, so I rely on newsgroups and message boards to find all my answers. So thanks again, I really appreciate it.

One more thing.....Pro/E understands "amplitude" the same way it reads "trajpar" or is that like creating a parameter within the sketch?

Thanks, Jason

Reply to
Jason L ©

"amplitude" is just a symbol, a name. Could be anything. The idea was just to get FREE_HT to be read before assignment to sd7 and see if there was an effect.

Reply to
Jeff Howard

Yes. (My reading comprehension skills are a little dull sometimes.)

`;^)

Reply to
Jeff Howard

I gather, from the extended converstation on this problem, that you are making a variable section sweep, using a circular trajectory and, then, getting the wavy feature with a trajpar formula. On top of this, you are trying to shortcut the input process with a number of parameters, used, hopefully, to govern the defining values of the wave and the washer profile.

You've already discovered the main drawback to this approach: Pro/e doesn't recognize any feature change so doesn't regen the model when you change some parameters. Many more difficulties exist with this procedure, especially when it involves a VSS with trajpar. Let me suggest a more robust, elegant alternative: a curve by equation.

With a curve by equation ('Insert>Curve>Equation'), you get a robust feature that changes when parameters change. The neat thing about using a curve by equation for your VSS trajectory is that Pro/e doesn't know if the feature has changed unless it evaluates the equation. Thus, all changes to parameters used in curve equations get evaluated immediately. So, your wavy trajectory for your VSS is capable of supporting a wavy feature that is infinitely variable.

Here is a wavy washer I created using the following parameters and equation:

Parameters waves=4 offset=2 height=.5 across=4

Equation (cylindrical csys) r=across theta=t*360 z=offset+(sin(t*360*waves))*height / offset just gives it a +/- distance from Z0

I could change any of these parameters with an immediate update of the curve trajectory and, thus, of the feature itself.

Reply to
David Janes

David, Is it z=offset +(sin(theta*waves)*height ?

  1. I don't see theta used but it is defined.
  2. The "/ offset" after height is confusing. MNM
Reply to
mnmca

Yes, thanks for the correction. I should have just done copy and paste instead of depending on memory.

Okay, this is copied from the equation input screen and it was as you suggested. I know this one's okay because it produces the wavy curve and it does vary by changing any of the parameters and regenerating the model. I did the VSS as a surface and turned it into a solid with 'Edit>Thicken'. If you do the thickening with the surface as midplane, the feature is almost indestructible.

If you want to make this really slick, do it all in a program ('Tools>Program'), i.e., set up the paramters, take prompted input to the parameters and even add relations to govern the width of the washer (or diameter of hole) and the thickness. And, if you want to be super slick, give this a java gui.

/* For cylindrical coordinate system, enter parametric equation /* in terms of t (which will vary from 0 to 1) for r, theta and z /* For example: for a circle in x-y plane, centered at origin /* and radius = 4, the parametric equations will be: /* r = 4 /* theta = t * 360 /* z = 0 /*------------------------------------------------------------------- r=across theta=t*360 z=offset+(sin(theta*waves))*height

Reply to
David Janes

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