Here is a little gizmo very useful for anyone who wants to turn some wooden rings :
It's a simple piece of wood, turned round with different steps of the different inner ring diameters you need.
Then the end of the spindle is cut on the bandsaw, along the axis, vertically and horizontally.
You chuck one end and the other end (the split end) is pushed against the live center, so that it will expend the shaft and hold the pre-drilled piece of wood in place.
And with this kind of tool, you can make this :