Multi-screw extruder for large format 3D printers

A method of extruding molten printing material,

• the method comprising:
• introducing a solid printing material to a plurality of isolated screw compartments within a multi-screw extruder;
• driving a gearbox of the multi-screw extruder and thereby rotating a plurality of extruder screws, wherein a corresponding one of the plurality of extruder screws is located in each isolated screw compartment, each isolated screw compartment being an independently-defined elongate cavity;
• activating a plurality of heaters substantially circumscribing each isolated screw compartment and thereby providing a heat flux into each isolated screw compartment;
• melting the solid printing material into the molten printing material within the plurality of isolated screw compartments;
• collecting the molten printing material in a common collection chamber from each isolated screw compartment;
• and
• extruding the molten printing material from a nozzle in fluid communication with the common collection chamber.

An extruder barrel assembly comprising:

• an elongate barrel body;
• a plurality of isolated screw compartments distributed throughout an interior of the body, each isolated screw compartment being an independent elongate cavity defined through a length of the elongate barrel body;
• one or more of heaters substantially circumscribing each screw compartment and operable to provide a heat flux into each isolated screw compartment;
• a common collection chamber provided at a bottom end of the elongate barrel body and in fluid communication with each isolated screw compartment;
• and
• a nozzle in fluid communication with the common collection chamber and providing a material outlet in fluid communication with a working area.