Okay, so we’ve gone through getting material prepped for printing- what’s next?
Let’s start with the gear! The lab is equipped with a Re3D GBX that’s been modified to print from recycled feedstock. Instead of using a traditional fused filament fabrication setup, the GBX uses a newer pellet-based printing system. This is a more recent development in the 3D printing world, known for being faster and more efficient. On our machine, systems such as the heating chamber and the extruder (the nozzle where liquid plastic is pushed out) have been widened to handle a greater variety of pellet sizes, since most pellet systems use a standard size. It has been such a treat working with the incredible Re:3D team and this groundbreaking machine
Learning as We Go
At the end of the day, ReCreateIt is a research project, and we find ourselves with a lot of opportunities to learn and grow. (read: failures.) Recycled materials aren’t designed to be melted down and forced through a 3D printer, so they’re far from optimized for it. As mentioned in our previous post, most of the material collected in the warehouse is polypropylene, which is well known for its tendency to warp when exposed to heat. Solutions for reducing warping often include applying glue to the print bed or carefully controlling the temperature as the part cools AFTER printing. This process is made easier by a fully enclosed print surface, which helps trap heat inside. Much of the printing process involves making adjustments on the fly. Tweaks to the print speed, the rate of plastic flow, and the distance from the nozzle to the bed can all be made to fine-tune each print based on the unique challenges of a project.
Embracing Imperfections
Even with strategies to work around the quirks of the materials we use, imperfections are still part of the process. Prints can warp, lift off the bed, or even cause clogs. Plastic can drip from the wide nozzle and leave little spiderwebs, and overhangs are almost impossible to print because of long solidification times. It is definitely an uphill battle, but we do our best with slicer adjustments and careful design that works with the specific strengths and limitations of our machine.
The Reward of Success
Working around unique challenges is mostly trial and error. Sometimes it can be a bit of a downer when projects fail again and again, but we have to remind ourselves that research is just as much about what doesn’t work as what does. The rush that comes from a successful print makes all the struggles worth it. We take a piece of someone’s trash, guide it through the long process of cleaning, designing parts, and troubleshooting the printer, and end up with something new that can go out and have its own life. It is incredibly satisfying to watch, and we feel so lucky to have a job that combines a passion for ecology with a love of tinkering.
