Step 5: Refinement

Picture of Refinement
Edit 9.jpg
Edit 9b.jpg
This step is why it's awesome to use Inventor.  After the 3D part is rendered, the sketches from which the revolutions were derived can still be altered.  Here I adjusted the splines and brought the ends of the two axis together on the top.  When turning, both axis will have the same center on one side.  The result is a slightly different shape with a nearly rotationally symmetrical head.