About Adjacent Geometry
When geometry is modified or transformed by a Creo Flexible Modeling feature, it is by default reattached to the model. Depending on the type of geometry involved, there are three possibilities to reattach the geometry.
• Extend the surfaces of the transformed or modified geometry selection and of the neighboring geometry until they intersect or until the hole where the geometry selection was originally placed is closed. This is the default option for non-tangent surfaces.
• Create side surfaces until the gap between the transformed or modified geometry selection and the hole left in the model is closed. The surfaces connect the corresponding edges in the hole and those of the geometry selection. This option is the default for tangent surfaces that are not planes.
• If tangency exists between geometric entities, you can choose to propagate the tangency so that it is maintained when the geometry is modified. When you propagate tangency, the geometry selection might be automatically expanded to neighboring entities based on their tangency to the selected entities.
The following Creo Flexible Modeling tools have adjacent geometry attachment options.
• 
Move • 
Offset • 
Modify Analytic Use the Attachment tab on the tool tab to change the default attachment options.