Add, delete, and move control points to modify a spline.
- Select the spline.
- Click Modify | Lines tab
Edit Spline panel
(Add Control) or 
(Delete Control). - Add Control adds a control point to the spline. Place the cursor over a spline chord and watch the status bar. When it says Reference, click to place a control.
A control point is added to the center of the chord.
- Delete Control deletes a spline control point. Select a control point for deletion.
The spline adjusts after control point deletion.
- Add Control adds a control point to the spline. Place the cursor over a spline chord and watch the status bar. When it says Reference, click to place a control.
- To move a control point, drag it to a new location.
- To move spline end points, select the spline.
- To move the entire spline, drag the end controls, which display as blue dots.
- To modify the spline curve between the end point and the next control point, select the end control, press Tab, then drag the end control point.