Abstract: Apparatus for adjusting the height above the floor of a plate to which is attached a pad in a rotary floor machine to accommodate pads having a range of thicknesses includes a yoke disposed about the generally vertical support shaft of a caster positioned within a centrally-located aperture in the pad in contact with the floor. The yoke is also disposed about and supports a rotational drive arrangement coupled to the plate and includes a ring bearing to facilitate rotational displacement of the drive arrangement within the yoke. One end of the yoke is pivotally coupled to the machine's housing, while a manually adjustable coupler attaches a second, opposed end of the yoke to the housing to permit raising and lowering of the yoke in a pivoting manner.