We constructed a ring Halbach array of strong NdBeB grade 52 arc-segment magnets, with magnetizations chosen to create a one-sided magnet with the field magnified on the flat side. We investigated a repulsive axial levitating forces and associated circumferential drag forces acting on an assembly of inductors suspended above the rotating array. After measuring induced currents, voltages and magnetic fields in the individual inductors (in the form of short solenoids) of our induction wheels, we investigated the dependence of lift/drag forces on the speed of relative rotation of magnets and inductors. The ratio of lift to drag increases uniformly with the angular velocity, as expected from a related theory of the induction effects in linear motion. We experimented with the shape and density of the various inductive loads made from air core inductors, and with their nonmagnetic conductive material to maximize lift. We have achieved a maximum lift of some 20% of the inductor assembly’s weight at our limiting speed of 2500 rpm. More development is still needed in order to obtain better and more accurate results. Eventually this design could have applications as frictionless bearings or as frictionless gear in a wide range of systems, especially in machinery that cannot be easily accessed. This paper has implications for ideas to build frictionless flywheels and hover boards.

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