Paste extruder (clay)

thingiverse

We crafted this clay extruder inspired by a syringe extruder, capable of accommodating syringes up to 100 mL. All design files were created with OpenSCAD and can be modified parametrically for flexibility. The original project featured one NEMA17 motor but for heavy-duty applications, two motors can be driven in parallel as seen in the image. A housing for two LM8UUs was initially designed but testing revealed it wasn't necessary. It's essential to pay attention to the positioning of the nut and nut coupling along with washers at the top, ensuring they don't obstruct vertical movement while allowing free screw rotation. The extruder was successfully mounted on a Prusa Mendel i2 but required careful experimentation to determine the optimal clay/water ratio and printing speed due to the printer's design. Using an hair-drier close to the nozzle helped stabilize the printed object. Next, we plan to integrate this device with a 3Drag, which allows the extruder to move solely on Z while the object is moved in the X-Y plane, eliminating the need for a tube and enabling thicker clay paste. The project was part of a thesis at the University of Pavia (Italy) by Raffaele Terranova.