Create and modify 3D models > Modify 3D geometry > Modify 3D geometry using dimensions > Modify 3D geometry using dimensions (3D annotations)
  
Modify 3D geometry using dimensions (3D annotations)
Creo Elements/Direct Modeling allows you to modify a 3D model, move a face, or position a part using dimensions (3D annotations). For an example, see Create a dimension (3D annotation). You can select specific 3D dimensions and initiate modeling commands to modify the 3D geometry. Such dimensions are called driving dimensions. However, you cannot use any dimension to modify 3D geometry; the dimensions that can be used as driving dimensions are listed in this topic.
To modify 3D geometry using a dimension,
1. Select a 3D linear, angular, or radial dimension in the viewport. The visual feedback shows the 3D CoPilot arrow, which you can drag to modify the face or the part connected to the dimension. The Command Mini Toolbar (CMT) opens.
◦ For linear dimensions:
▪ Select the rightmost part of the dimension to modify the face or part on the right-hand side.
▪ Select the midpoint of the dimension to modify the faces or parts symmetrically on both sides.
▪ Select the leftmost part of the dimension to modify the face or part on the left-hand side.
◦ For angular dimensions: The face or part that is modified depends on the selection of the angular dimension. For example, if you select an angular dimension between two perpendicular faces of a cube at a point closer to one face, then that face is modified.
2. You can either drag the 3D CoPilot or type a value to modify the face or the part. You can also execute the default command or choose an alternative command on the CMT, and then drag the 3D CoPilot to modify the face or the part. See Using the Command Mini Toolbar (CMT) for details.
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• After selecting a dimension, the default command that is invoked depends on the type of dimension and the geometrical element to which the dimension is connected.
• If the 3D Documentation module is active, the CMT shows 3D Documentation commands.
• Select a dimension and use the CMT to modify the 3D geometry. You can also move or delete the dimension using the CMT.
3. Click to complete the operation.
To activate module:
1. Click Files > Modules
2. Click Applications.
3. Click 3D Documentation under Included section.
You can use the following dimensions as driving dimensions to modify 3D geometry:
Linear dimensions:
• Click 3D Documentation and then, in the Annotate group, click Linear to create 3D distance dimensions. You can use these 3D distance dimensions as driving dimensions.
• Click 3D Documentation and then, in the Annotate group, click Coordinate to create 3D coordinate dimensions. You can use these 3D coordinate dimensions as driving dimensions.
• Click 3D Documentation and then, in the Annotate group, click Datum Long to create 3D baseline dimensions. You can use these 3D baseline dimensions as driving dimensions.
• Click Feature and then, in the Annotation 3D group, click New. You can use these linear dimensions as driving dimensions.
Angular dimensions:
• Click 3D Documentation and then, in the Annotate group, click Angular to create 3D angle dimensions. You can use these 3D angle dimensions as driving dimensions.
Limitations
You cannot use the following dimensions as driving dimensions to modify 3D geometry:
• 3D GD&T dimensions
• 3D dimensions with measured value zero
• 3D dimensions which reference 2D geometry
You cannot use 3D dimensions as driving dimensions if the reference element:
• Belongs to a read-only or a graphical part.
• Is a feature point or a coordinate system.
• Is a 3D B-spline geometry.
Creo Elements/Direct Modeling displays an error message if any of the following occurs:
• The modeling operation is not successful.
• The specified value of the dimension is greater than the acceptable value.
• The 3D dimension is deleted. A dimension is deleted if its specified value is very large.