Use CAD software to turn 2-D mechanical designs into 3-D mechanical models. 3-D modelers to refer to the technique of stretching a 2-D shape into 3-D space. Performs this expansion by first extending a new axis at right angles to the 2-D axes on which your 2-D design sits. It then makes a copy of the 2-D shapes you are expanding at a higher location on the axis, while keeping the original shapes at the base of the axis. After converting your 2-D design to 3-D, display it with realistic lighting and shadows using the "Render" command on the Render tab.