A rotating separator disk is movable between sheet material articles in a stack of sheet material articles. A variable speed drive which is connected with the separator disk and rotates the separator disk. The variable speed drive is operable to vary the speed of rotation of the separator disk between a high speed and a low speed during each revolution of the separator disk. First and second restrictor members engage a sheet material article in the stack of sheet material articles. A suction applicator head is operable to disengage one sheet material article from the first restrictor member. A leading edge of the rotating separator disk is then moved between the one sheet material article and an adjacent sheet material article. As this occurs, the speed of rotation of the separator disk is increased and the one sheet material article is disengaged from the second restrictor member by the separator disk.