Hi All I am considering a project to manufacture a ring with a spinning centre band but have absolutely no idea how to do it.
I have not read every suggestion so this may have already been
submitted or it may not be practical, but have you considered
hammering the edge of the inner band to hold the outer band?
Make two rings one that fits inside the other, the inner band will be
wider than the outer band, slip the outer band in place, lay on an
anvil and carefully hammer the edge of the inner band. This should
cause the inner band to mushroom out (like a rivet) and hold the outer
band…it will also mushroom towards the inside and you will need to
cut or file the inside ridge away.