Creating 3d objects in AI

Hello,

I am new to creating 3D objects from paths in AI. When I create a simple path (or half of the final object I want to be 3D), and then use the Effects\3D Materials\Revolve option, the results are just a round shapeless 3D object. It loses the shape of the half path I created which shoud have completed into a completed 3D shape of the half path.

Any help will be greatly appreciated.

Best,

Mark