An apparatus for chemical mechanical planarization (100). The apparatus has a platen assembly for holding an object (e.g., wafer, disk, flat panel, glass) to be planarized. The apparatus (100) also has a polishing head coupled to a polishing pad, which has a smaller diameter than the object. The polishing head is movable (e.g., pivotable, rotatable, translational) from a first region overlying the platen assembly to a second region, which is outside the first region. A removable substrate is coupled between the polishing pad and the polishing head. The removable substrate is removably coupled to a coupling on the polishing head. The apparatus also has a first magazine (511) disposed in the second region, where the first magazine houses at least one substrate comprises a first polishing pad to be placed on the coupling on the polishing head. A second magazine (513) housing at least one substrate comprising a second polishing pad may be provided in the second region. A disposal site (502) may also be provided in the second region for receiving a used substrate or a faulty substrate.