Create drawings from models (Creo Elements/Direct Annotation) > Modify drawings > Add and modify geometry > Auxiliary geometry > Modify center lines and symmetry lines
  
Modify center lines and symmetry lines
You can extend existing center lines and symmetry lines, and rotate center lines by specifying a point or angle.
To modify center and symmetry lines,
Click a center or symmetry line handle and drag it to extend the line.
Click anywhere on a center line except the handle to rotate the line.
Click on an arc symmetry line to extend it (if the arcs have the same center point).
If you are accustomed to our earlier versions, you can still use the original menus:
To extend or contract an existing center line or symmetry line,
1. Click Annotation and then, in the Annotate group, click the arrow next to Cen Line.
2. Click Extend.
3. Select the end of the center line or symmetry line to be extended.
4. Click the point to which the line is to extend.
5. Continue selecting center lines or symmetry lines, or click to end the operation.
To rotate an existing center line by specifying a point,
1. Click Annotation and then, in the Annotate group, click the arrow next to Cen Line.
2. Click Rotate by Point .
3. Select the end of the center line to be rotated.
4. Click the point to which the center line end is to rotate.
5. Continue rotating center lines, or click to end the operation.
To rotate an existing center line by specifying an angle,
1. Click Annotation and then, in the Annotate group, click the arrow next to Cen Line.
2. Click Rotate by Angle .
3. Select the center line to rotate, define a selection box, or use the Select tool.
4. Enter the rotation angle in the Angle box.
5. Click to complete the operation.