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I have a Creo 3d assembly model in which I want to create a section thru some internal components. I have a cross section thru the entire assembly. When I activate that cross section and go to create a new cross section referencing one of the internal parts, the original main cross section is undone and I can't see inside.
PTC tells me this is normal functionality.
You should be able to mix a general section with a local section.
Not immediately obvious, but I'm pretty sure I've done it before.
On the drawing you can add local sections to a section view, but in the assembly it deals with one at a time. You can place the components that obstruct the view on a layer and then blank that layer in order to ease making the new internal-part section. I think it can be done with a simplified rep, but I don't recall if it results in the section depending on the simplified rep in some way.
AFAIK it is normal.
This problem is happening within the 3D assembly, not within the drawing.
PTC recommends creating a zone (I haven't done this before) cross section to show the internals.
I just hide the offending components.