A chuck useful for supporting a wafer during an edge bevel removal (EBR) process comprises a rotatable center hub having a plurality of support arms extending outwardly from the rotatable center hub, support pins on ends of the support arms, gas passages extending through upper surfaces of the support pins, and gas conduits in the support arms. The gas conduits supply gas to the gas passages or apply a vacuum to the gas passages. The support arms can include alignment cams which are rotatable from an outer non-alignment position away from a periphery of the wafer to an inner alignment position at which the wafer is centered. During centering, the wafer is floated on a gas cushion which reduces wear of the support pins.