Here is a unique object produced from a similar process.




This one started off as a Revolved-by-Rail cylinder made with a grid of 24x18 control points.
Some odd points were scaled in, while evens were scaled out to even the outside.
An inner circle was trimmed in the Z direction to 'gut' the inside shapes, then I used Twist.

Could be an old push-mower blade, or some kind of exhaust grate.