Raw pellets are generally not manufactured with 3D printing in mind, most are intended for large-scale injection molders. Their particle size and geometry can vary greatly depending on polymer type or individual supplier, and some present greater difficulty than others when traveling through the feed throat of a vertical extruder such as the MDPH2 or MDPE10. Since the pellets’ route through the feed tube of the extruder and into the throat of the screw and barrel assembly is driven by gravity, it can fall prey to obstructions if the individual pellets are especially large or sharp-edged. Regrind is another example of a feedstock material that is especially problematic due to bridging in the feed throat. Once an obstruction forms, it often leads to feed starvation which will create an underextrusion scenario, eventually inducing a failure state for the print.
The Feedstock Agitator from Massive Dimension safeguards against material bridging by delivering vibration to the feed throat extension at customizable intervals matched to extrusion speed and material geometry. An ultra-compact pneumatic linear actuator delivers vibratory force to the feed throat extension, operated through a control box that allows for fully adjustable on and off times. No wiring is required, and timer adjustments are made through easily understood dials on the control box. Just plug it into the wall and route your compressed air lines and you are ready to go!
Whether you have an MDPH2 or MDPE10, modification to the machine is simple and straightforward and can be done with minimal tools and time. The mount for the linear actuator is incorporated into a new elbow that is a direct replacement for an existing piece of the feed throat extension. The user just needs to remove the extruder enclosure and swap out this piece, requiring little more than a screwdriver, Allen key, and adjustable wrench.
Don’t be frustrated by stubborn materials that create feed throat obstructions and abort your large format prints- agitate your feedstock and keep the extrusion flowing!