Abstract: A method is disclosed for erecting flat carton blanks into a tubular configuration, folding the minor flaps inwardly normal to the minor sides in three steps at a first work station, moving the erected carton blank to a second work station while partially folding the major flaps toward the folded minor flaps and applying glue to the minor flaps, further moving the carton blank to a third work station where the major flaps are pressure sealed to minor flaps and then discharging the finished carton from the work area. A machine for performing the method includes unique motor driven chain drive assemblies that enable adjustments to accommodate various size carton and a cam regulated valve system to control application of vacuum to suction cups and compressed air to a glue gun and to pneumatic pistons that move control arms and the like.