Metal Extruder and Syringe Pump

thingiverse

The final three-part mini-series episode focuses on making things using low-melting-temperature alloy, creating a hot material transfer system that can extrude molten metal or wax. This is inspired by Dr. Sells and Prof. Bowyer's work. Remember, low-melt alloys are toxic and dangerous, so only handle them if you have lab experience. Wax handling is safer but still requires caution. Possible uses for a wax system include automated wax casting and using wax as support material. A standard RepRap prints layers of plastic (like HDPE or ABS), then the metal/wax toolhead deposits molten material in the formed channels or cavities. The system includes a heated cup, heated copper nozzle, syringe pump, and heated plate for optimal performance. Safety measures are essential as the nozzle, cup, and plate get extremely hot. Use good ventilation, avoid unattended operation, and know your fire extinguishers and escape routes. The cup heaters were purchased from American Science and Surplus, while the copper nozzle was derived from the old RepRap Thermoplast Extruder V1.1. A syringe pump and heated plate complete the system. For electrical interface, it is compatible with older single-Arduino setups. Necessary parts and materials include copper bar stock, PTFE bar stock, cable ties, hose clamp, JB weld, silicone caulk, superglue, 12cc disposable plastic syringes, 0.2 inch thick acrylic, a Solarbotics gear motor, two microswitches, assorted nuts and bolts, wire, and connectors.