Here's an example of clam edge, and what the geometry should be. The larger examples are the same curves, just widened to bring out the difference.
Current state of the wheel, clam edge edition:
You can see the change near the edge, where it should be even, is fairly abrupt. If you look closely, you can also see signs of the hamon coming out.
You can see fairly clearly the "dips" I wrote about last night, and the clam edge is pretty evident as I haven't done much to smooth that out yet.