Prepare two plastic turntable ,copper roller and drill holes
for mount magnets installation on bottom side.
Top side insert magnets and setup magnetic pole.
Buy a cooking pot and modify it for suitable assembly turntable later.
Modify pot to be a magnet mount rack. 12 pcs alnico magnets will on this rack.
The magnet rack drill a big circle for embed a plastic turntable.
Embed together to find screw hole distance.
Try turntable rolling on magnetic floating platform and estimate distance of float.