Abstract: Technologies are provided herein for a modular deposition tool design that allows for both, the fast interchanging of materials and for easy cleaning of all wetted surfaces. A drive assembly for use in a solid freeform fabrication system, includes a drive module having a drive mechanism and a detachable material bay assembly that is detachable from the drive module. The material bay assembly includes a material bay holder, a material deposition tool, and a corresponding material bay actuation mechanism that can engage with the drive mechanism of the drive module when the material bay assembly is coupled to the drive module such that when the drive mechanism of the drive module is actuated, the material bay actuation mechanism is actuated, which causes the material deposition tool to deposit material from a material bay inserted in the material bay holder.