Abstract: Apparatus for coating successive batches of workpieces with respectively different paints, composed of a plurality of coating tank units disposed along a conveying path and each arranged to hold a bath of a respective paint, a workpiece conveyor extending along such path for conveying workpieces therealong, a carriage movable along the conveying path to the region of a selected one of the tank units, and a conveyor guide structure carried by the carriage for controlling the movements of the conveyor in order to cause workpieces being conveyed by the conveyor to be immersed in the bath contained in the selected unit where the carriage is located.