Abstract: A centrifuge (10) is provided with a cantilevered shaft (18) upon which the main drive rotor (26) is located. A bobbin (62) is attached to the planetary gear shaft (44), which is driven in planetary motion by the rotation of the rotor (26) and its toothed engagement with the shaft (18) of the cantilevered rotor. A flying lead section (72) extends from the bobbin (62) through an aperture in the cantilevered rotor (26). The arrangement provides a centrifuge structure which can handle higher rotational speeds while maintaining resolution. The flying lead section (72) provides a simple path for the inlet and outlet leads (84,86) which reduces dead volume and increases reliability. The bobbin (62) supports at least one coil (68). Rotor component (44) includes at least one bearing (50, 52).