1. Open a sketch on the front face of the back plate. Select the Convert Entities Tool from the Sketch Group of the CommandManager, and click on the two circular edges

indicated in Figure P1.8C. Click the check mark to create circular entities in the sketch. Draw two lines from the edge of the hub to the edge of the back plate. The top line should be tangent to the edge of the hub. The bottom line should be parallel to the top line. Add a 5-mm dimension between the two lines. Although the radial alignment of the lines is not critical, making one of the lines horizontal will make the sketch fully defined. FIGURE PI.8C 2. Extrude the sketch contour bounded by the lines and circles to the same 30-mm depth as the hub (try using "Up to Surface" as the type of extrusion) to create the first vane on the impeller. Add a 5-mm fillet at the base of the impeller, and use the Circular Pattern Tool to create a pattern of six vanes and radii, as shown in Figure P1.8D. FIGURE PI.BD R5 3. Add the 5-mm-thick front plate, which has a 75-mm-diameter "eye" to allow fluid to enter. Convert Edges to Sketch Entities