To Create a Draft Entity Using a Model Edge
You can convert existing model edges to draft entities, which enables you to modify the geometry display within the drawing. Any changes you make do not affect the three dimensional geometry in the model.
1. Click Sketch > Edge. The Select dialog box opens.
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You can also click Legacy Sketch > Edge.
2. Select the model edge to use. To select multiple edges, hold down the CTRL key and select the edges.
3. Click OK in the Select dialog box to confirm the edges you selected. The model edges are converted to draft entities.
4. Drag handles appear on the newly converted draft entities. Modify the draft entities as necessary. If you chose to erase the model edges, applicable model edges are erased when you modify the new draft entity.
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When using parametric sketching, you can automatically erase the applicable model edges that exist behind the newly created draft entities. Set the Erase model edges behind draft entities option in your sketch preferences (Click Legacy Sketch > Sketcher Preferences).