I am having problem with orientation of the slinky cross section on the rail revolution. The cross section of the arched slinky reveals that the orientation of the cross section does not properly follow frames perpendicular with arch.
This looks really good. Interesting solution to develop the individual rectangles and then sweep them on the rail. I believe you solved my problem. Thank you for your help.
On my original model I added another rail at a slightly smaller radius and used the Sweep2 command.
Using Sweep2 with both rails, the rectangles behaved properly and stayed perpendicular to the rails.