An additive manufacturing system has a plurality of manifolds in an extruder. Each manifold is connected to at least one nozzle of the extruder so the at least one nozzle extrudes thermoplastic material through a corresponding aperture in a faceplate mounted to the extruder. A plurality of valves is configured between each manifold and each nozzle connected to the manifold so the nozzles connected to a manifold extrude thermoplastic material from the manifold selectively. The faceplate is also configured for rotation about an axis perpendicular to the faceplate so different orientations of the nozzles and the apertures of the faceplate can be obtained. The different manifolds of the extruder enable a plurality of thermoplastic materials having different properties to be extruded simultaneously so the materials can join to one another while the materials are at an elevated temperature.