Copyright Goodheart-Willcox Co., Inc. 88 AutoCAD and Its Applications—Advanced Next, right-click on the UCS icon and select Rotate AxisY in the UCS icon shortcut menu. Enter 60 for the rotation angle. Watch the position of the UCS icon change when you press [Enter]. See Figure 4-12D. If the view cube is set to be oriented to the current UCS, then it rotates when the UCS is changed. Additionally, the grid rotates to match the new UCS. If the grid is not on, turn it on by pressing [Ctrl]+[G]. Remember, the grid is displayed on the XY plane of the current UCS. The new UCS can be used to construct a cone with its axis projecting from the center of the sphere. Figure 4-13A shows the new UCS located at the center of the sphere. With the UCS rotated, rectangular coordinates can be used to draw the cone. Enter the CONE command and specify the center of the base as 0,0,1.5 (the radius of the sphere is 1.5 units). Enter a radius of .25 and a height of 1. The completed cone is shown in Figure 4-13B. You can see that the axis projects from the center of the sphere. Figure 4-13C shows the objects after setting the Conceptual visual style current. This same basic procedure can be used in the tank and pipe example presented earlier in this chapter. To correctly locate the pipe (cylinder), fi rst move the UCS origin to the point previously located on the surface of the cylinder. Next, rotate the UCS 30° about the Z axis. Then, rotate the UCS 90° about the Y axis. The Z axis of this new UCS aligns with the long axis of the pipe. Finally, use rectangular coordinates to draw the cylinder with its center at the point drawn in Figure 4-5B. Once you have changed to a new UCS, you can quickly return to the WCS by picking WCS in the view cube drop-down list or by picking World in the UCS icon shortcut menu. The WCS provides a common “starting place” for creating new UCSs. UCS Ribbon Home Coordinates Visualize Coordinates Y Type UCS A B Rotated 30° about the Z axis 30° Centerline of cone Rotated 60° about the Y axis C D 30° 30° 30° 30° Figure 4-12. A—The world coordinate system. B—The new UCS is rotated 30° in the XY plane about the Z axis. C—A line rotated up 30° from the XY plane represents the axis of the cone. D—The UCS is rotated 60° about the Y axis. The centerline of the cone coincides with the Z axis of this UCS.