Redefining a hole

[jflatt]

I have a series of holes on a planar surface. The surface was created with a blind extrude to a dimension. I wanted the extrusion height to be dimensioned to a different feature than the sketching plane, so I created a plane referencing the desired feature and made the extrude up to that surface. When I did that all of the holes "lost" the surface they were anchored on, even though it's the exact same surface of the exact same feature only dimensioned differently. So now I have to go through and redefine the placement surface for all the holes. Only when I redefine the surface, Creo (4.0) repositions the hole based on where I click the "new" surface and redefines all the offset dimensions I had locating the hole. I tried every different way I could think of, but in the end I had to redefine all the holes after writing down all the dimensions I had locating them as well as deleting all of the mirrors/patterns I had of these holes and doing those completely over from scratch. Did I miss something? Is there a way to define the hole placement surface without defining the location?

[tbraxton]

When you changed the height of the extrude feature did you reroute the references or recreate the feature? It sounds like the hole lost a reference when you changed the extrude. In theory if you rerouted the depth reference of the extrude then the hole should update but without seeing the model it is hard to say what actually happened.

In a case like this you can often make the model more robust to edits by using intent references (hole placement plane) or create datum references to "anchor" features that are children of those likely to change.

[kdirth]

Changing the extrude depth from Blind to Up to Selected does seem to change the identity of the surface.  Possibly because Up to Selected does not create a "planer" surface.  Your example is a planer surface since it is up to a plane, however up to selected can also create a 3D surface.

To fix, do not redefine the feature.  I suggest using Edit references.  In this case it is a bit tricky because Edit references does not show a missing reference.  However, it is known which reference changed.  The first reference is always the plane of the sketch or the hole start.  Select the "new" surface for the first reference and select OK.

I would also say this "glitch" may be worthy of a support case or Idea.  The hole function does not seem to be able to follow the change from a surface created by a blind extrude to a surface created by an up to plane extrude.  The extruded (sketched) hole, I created, followed the change, but exhibited the same irregular behavior in the refererences (Edit references does not show it missing, but also does not highlight the surface or show an outline of the original as it would normally for a missing reference)

 

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