[Wayne C.]

the rack just slides around on the carpet and is held in a rough position by the chains attached to the fixed central plate. As I understand it, they will give the rack a slight twist each time to reposition the prongs. That means the width of the side alleys will also be variable to some extent

The whole thing is quite heavy. I dont know if it is legal to grab it and keep it spinning (but we thought of that).

The spokes are somewhat rigid in place but if you jar them they will rock around.