Researchers have developed an improved version of a desktop extruder that makes filaments for 3D printers, and they have made assembly instructions available online for free.
Students at Michigan Technological University in Houghton, Michigan, developed a version of what is known as the Recyclebot, a small plastic recycling system.
“We have developed a new version of the Recyclebot that has sufficient control to make commercial filaments from more or less everything. We have demonstrated this with pellets, regrind, and even waste composites like wood, ”wrote Joshua Pearce, professor at Michigan Tech on the plastics recycling update. “The plans are completely open source and most of the parts of the new machine design are 3D printable themselves.”
In an interview, Pearce said he saw opportunities for plastic recoverers in a number of areas. First, the equipment is an inexpensive way to test composites and polymer blends. Reclaimers can also use it to make 3D printer filaments, a relatively small market where the markups are still huge. With the wider use of the Recyclebot extruders, reclaimers have a new market in which to sell flakes.
“It’s still a small market … but it’s growing a lot,” he said. “This might be something some of them would be interested in and our device can help them get to market right away.”
Creating the Recyclebot
Full plans and assembly instructions have been published in Elseviers HardwareX. This document explains how to create a model called the RepRapable Recyclebot, so named because it is aimed at a 3D printing community that the paper says is focused on self-replicating open source rapid prototypes called RepRaps, concentrated.
According to the online article, a RepRapable Recyclebot can be made for less than $ 700 in materials and can be made in about 24 hours. The RepRapable Recyclebot produces filaments for 3D printers at a rate of around 1 pound per hour and 10 minutes. For every pound produced, 0.11 kilowatt hours of electricity are used.
The researchers estimate that filaments made from commercial pellets can account for about a fifth of the cost of commercial filaments. It can recycle waste plastic into filaments for about 1.1 cents per pound, compared to over $ 11 per pound for commercial filaments.
The system can process polymers with extrusion temperatures below 250 degrees Celsius. It is “able to manufacture custom filaments through a wide range of thermopolymers and composites for materials science studies of new materials and recyclability studies, as well as for researching novel applications of 3D printing based on molten filaments,” the paper states.
The paper acknowledges that this is not the first desktop-sized extrusion system that has been developed and the plans of which are made available to anyone. The plastic recycling update looked at other desktop extruder products, many of which were mentioned in the newspaper, and that publication wrote about one back in January 2013, the Filabot.
However, developers of the RepRapable Recyclebot say it is made up of parts that can be found at hardware stores or purchased online. In addition, many of the parts can be 3D printed so filaments from the device can be used to make another.
In addition, the paper points to other unique features, such as an adjustable hopper size and shape with emptying function, an aluminum cooling path for more cooling than with passive or compressed air processes, an adjustable crossbeam for different coil sizes and a modular structure for the addition of water bath cooling, pelletizers or injection molding system.
“These properties make it ideal as a research system for those studying novel filaments,” the paper says.
Pearce said he plans to have his students use the equipment next fall semester to make as many different polymer composites as possible.
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