Abstract: A method and machine for forming longitudinally curved tooth surfaces in bevel and hypoid gears. A dish-shaped grinding wheel 26 is rotated about its axis 76 and oscillated about a cradle axis 66 in a timed relationship with a relative reciprocation of a work gear 20 along cradle axis 66. The timed relationship is defined by a power series equation to permit a simultaneous form grinding of adjacent tooth sides of one member of a work gear pair to be appropriately mismatched with simultaneously generated adjacent tooth sides of the mating member of the gear pair. A dish-shaped grinding wheel 176 having inner and outer stock removing surfaces 178, 180 for working opposite sides of gear teeth is also used in accordance with special timed motions of the present invention to improve contact characteristics between mating gear teeth.