A timed feeder for feeding corrugated boards to nip rolls of a box finishing machine. A feed member is raised to the feed path to engage and drive a board to the nip rolls and then lowered away from the feed path until the next cycle. An indexing drive mechanism, driven by a computer-controlled servo motor, activates the feed member and has a feed phase when it drives the board to the nip rolls, and a dwell phase when the feed member is away from the feed path and the output shaft of the indexing mechanism is at zero velocity. During the feed phase, the output shaft of the indexing mechanism accelerates the feed member and the board beyond the nip roll velocity and then decelerates them to the nip roll velocity at the point where the board enters the nip rolls. During the dwell phase the input shaft which was at constant velocity during the feed phase, is either accelerated and then decelerated or decelerated and then accelerated to shorten or increase the duration of the cycle allowing different size articles to be fed with minimum or zero spacing downstream of the nip rolls.