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tbraxton
22-Sapphire II
22-Sapphire II
January 21, 2021
Question

Geometry check present when creating a round feature

  • January 21, 2021
  • 1 reply
  • 3422 views

I have a round feature that is throwing a geometry check when modeling the same underlying geometry created differently. The round appears to be there and accurate visually.

I am looking for an explanation of the root cause of this error. This is a simplification of a much more complex model that includes the same geometry. The production model uses a mirror part geometry as only half the part is explicitly modeled. This is the only geom check in the model and I have not been able to get rid of it. I have tried datum reference surfaces for the mirrored boss but that did not resolve the error. Does anyone have any insight into why this error is generated?

 

1) Both models (Creo 4) use the same absolute accuracy and are included here for reference

2) Both models share geometry that is congruent

3) Only the model that mirrors the 180 degree revolve feature throws the error (mirr_part_geom_check.prt)

 

The error is:

 

Set cannot be constructed on the highlighted pair of surfaces.

Recommended actions:

 Try to create feature as "Unattached", and complete it using quilts.

 

 

1 reply

16-Pearl
January 21, 2021

Hi, 

 

It seems like Round4 is causing the issue. In this feature, you are selecting two surfaces, the outer surface of the Revolve1 and the perpendicular surface inside Revolve2. This is a fine way of doing things but it seems like it's getting confused when you mirror the geometry. Take a look at the the round in the non-mirror part. The surface references look correct. In the mirror, the same round feature shows the outer surface of revolve 1 on the other "side" of the part. Like I said, I'm not sure but it seems like mirroring is flipping your reference to the opposite "side" of the part. 

 

Delete your pattern and redefine round4 to the edge and then repattern. This seems to fix the issue. 

 

tbraxton
22-Sapphire II
tbraxton22-Sapphire IIAuthor
22-Sapphire II
January 21, 2021

Did you delete all of the patterns or just the one for round 4? I just tested your suggestion in Creo 4  M110 and the model does not regenerate. The mirror fails when patterning round 4. I had tried this previously with the same result.

 

If I delete all of the patterns (not just round 4) and then recreate them and use the edge for round 4 then it does regen and the geom check is not thrown.

 

 

 

16-Pearl
January 21, 2021

Sorry! I should have clarified the steps a little better. It's a bit confusing when you have a geometry dependent mirror. 

 

  1. Open REV_360_TEST.prt
  2. Delete the pattern of Round4
  3. Redefine Round4 to the edge
  4. Repattern Round4
  5. Regen if you need to
  6. Open MIRR_PART_GEOM_CHECK.prt
  7. Delete the pattern of Round4
  8. Redefine Round4 to the edge
  9. Repattern Round4
  10. Regen if you need to