Chapter 2 Creating Primitives and Composites 29 Copyright Goodheart-Willcox Co., Inc. Note UCS orientation Height Rotation Polar tracking vector Indicates a positive Z value Angle from the XY plane Height B A Figure 2-9. A—If polar tracking is on, you can rotate the cylinder axis 90° from the current UCS Z axis and then move the cylinder to any angle in the XY plane. B—If the polar tracking vector is moved parallel to the current Z axis of the UCS, the tooltip displays a positive or negative Z dimension. Center Left Right Figure 2-10. When you begin the POLYSOLID command, use the Justify option to select the alignment.