After the 3D object has been imported into the symbol (mine is called cpu_rotate) and centered in the window, it's ready to be optimized. This involves deleting extraneous geometry, which reduces filesize (enormously) and gives the object a look that truly sings.
To do this, start by selecting the artwork in every frame (follow the preceding steps 14), then follow these steps:
Now, delete any line segment from the artwork that doesn't either define that CPU's shape or fit your intended style. Figure 05:12 shows what I ended up with.
Exercise the previous two simple steps for every frame in the animation. The results are often stunning. This animation, when fully optimized, weighs in at only 2k and plays smoothly with a full ten frames (see (see figure 05:13).
A good tip to use when deleting geometry, especially single lines, is to hold down the Delete key while clicking on the things you want to delete. The offending geometry is zapped away the moment you click.