| Abstract Scope |
Large-format material extrusion (LFME) systems are limited in their ability to produce parts with overhanging features. This is due to (i) the use of screw-style extruders, which render material changes for depositing a release material mid-build impractical, and (ii) the use of post-process machining tools, which cannot access all deposited features, to remove the sacrificial support structures. The authors address these constraints through a novel multi-material process in which a water-soluble material is deposited via a secondary extruder to serve as a sacrificial interface between the printed support structures and part. After printing, the interfacial layers are dissolved, allowing the support structure to be removed without post-process machining. Additionally, a method for dividing the printed support structures into smaller, removable chunks is demonstrated to enable facile removal from complex, hollow large-scale printed objects. Utilizing these processes in conjunction, a geometry was manufactured that would traditionally be considered un-manufacturable in LFME. |