A printing machine is provided for imprinting forms with fixed data from embossed printing plates and variable data from manually settable print wheels by moving a roller platen from a start position across the printing elements and the form to an actuated position to perform a printing operation and back to the start position to complete a printing cycle. The print wheels are selectively positionable by keyset levers movable from a zero position to a selected printing position for rotating each of the print wheels to a desired peripheral setting. Reset means is provided for restoring each of the keyset levers from the selected printing position to the zero position in response to movement of the roller platen through a printing operation, and lock-out means is provided to inhibit movement of the roller platen through a printing operation following a printing cycle. The roller platen is unlocked for movement in response to movement of at least one of the keyset levers from the zero position to a new setting.