Using Centerlines in a Sketch Centerlines promote symmetry when sketching.  In this example, we want a rectangle to be sketched symmetrically about the vertical and horizontal references.  Centerlines display as a yellow dashed line.

1. In the Sketch dialog box, notice that datum plane DTM1 is automatically selected as the Sketching Plane.
• Click Sketch from the Sketch dialog box.
• Click Datum Planes from the main toolbar (top of the screen) to disable their display.
• Click No Hidden from the main toolbar.
• Notice the two dashed lines, these are sketcher references.  Sketched geometry will snap to these references.
2. Sketch centerlines and a rectangle as shown in the following figure:

• Click the black arrow on the Line Types Flyout  in the sketcher toolbar (right of the screen), and select Centerline .
• Click two locations on the vertical sketcher reference to sketch a vertical centerline.
• Sketch another centerline on the horizontal sketcher reference, as shown in the following figure on the left.
• Click Rectangle from the sketcher toolbar (right of the screen).
• Click and release to select a location for the upper left corner of the rectangle.
• Allowing the rectangle to snap to symmetry, click and release to select a location for the lower right corner of the rectangle.  Refer to the following figure.

Sketching Centerlines and a Rectangle

	Always use a 'click-and-release', 'click-and-release' technique when sketching geometry, as opposed to holding down the left mouse button and 'dragging'.