A tool head for use in a 3D printer includes at least two drivable tools, at least one of which is an extruder tool for melting a modeling material suitable for building an object in layers. A shared or common drive system for the at least two drivable tools serves, in the context of the at least one extruder tool, to feed the modeling material into an extrusion unit. A selection device can establish an operative connection between at least one tool selected from the number of drivable tools and the drive system.