Creating the volume by revolution

1. Rotation of the profile will be carried out in two rotations of 180 degrees each. This way, the figure will be defined by a greater number of points.

2. From the Copy window, select Lines and Rotation. Enter an angle of 180 degrees and from the Do extrude menu, select Surfaces. The axis of rotation is that defined by the line that goes from point (0, 0) to point (200, 0). Enter these two points as the First Point and Second Point. Be sure to enter 1 in Multiple Copies.

3. Click Select. For an improved view when selecting the profile, click Off the "aux" layer. Press ESC when the selection is finished. The result should be that illustrated in Figure 14.

Figure 14. Result of the first step in the rotation (180 degrees)

4. Repeat the process, this time entering an angle of -180 degrees.

5. To return to the side view (elevation), choose Rotate Plane XY.

6. Choose Render Flat lighting from the mouse menu to visualize a more realistic version of the model. Return to the normal visualization with Render Normal. This option is more comfortable to work with.

Figure 15. The pipe with disks, created by rotating the profile .

NOTE: To select the profile once the first rotation has been done, first select all the lines and then delete those that do not form the profile. Use the option Rotate Trackball from the mouse menu to rotate the model and facilitate the process of selection.