This year, Science teacher Jennifer Long and Art teacher Christian Tonsgard explored the possibility of implementing a 3D printer into their courses. The MakerGear M2 printer can extrude material at thicknesses as low as 0.1 mm, which is as thick as two sheets of paper! Our ultimate goal was to create an object with the 3D printer that we could then cast in ceramics. While we didn’t quite get there, we were able to weigh the pros and cons of implementing this technology in two different subject areas.
We tried printing with two different materials, PLA (polylactic acid) and ABS (acrylonitrile butadiene styrene). PLA is made from organic material (cornstarch and sugarcane) and as a result, is more biodegradable. It has a lower melting point, requiring lower temperatures to print, but is a bit more prone to breaking. This can be useful as you can cut, file sand and paint it but it can limit its application if you want to print parts to bear weight. In contrast, ABS is an oil-based plastic that is both strong and sturdy. Unlike PLA, it tends to bend instead of break. It can’t really be painted or sanded easily, but it is possible to get a glossy finish if treated with acetone or other solvents after printing. ABS also has several cons in that its high melting point requires the print bed and extruder to be at higher temperatures. In addition, ABS produces fumes when melted during printing and needs to be in a well ventilated area. For these reasons, we primarily printed with PLA.
Our initial goals were to practice printing with free designs available online to evaluate the ease of use. There are several websites that provide free downloads of others’ designs and very little adjustments had to be made before using these files with our printer (www.thingiverse.com,
https://pinshape.com/, www.3dprint.nih.gov.) We discovered that the printer was relatively easy to use once the print began. However, before each print, the distance between the extruder and the print bed had to be adjusted. Most of the time, this was quick and easy, but at times could take nearly a full class period to tweak. We printed a range of files that required print times between 20 minutes and 6 hours. In the end, printing already available 3D print files was easy to accomplish and students were fascinated watching and learning about the process. The printer lived in an office next to one of the chemistry classrooms and the students always wanted to see what was being printed!
Our second goal was to investigate the variety of 3D modeling software platforms available. These include Sketchup (which is used by Mike Willey’s Engineering class to design green building projects), Blender, TinkerCAD, Solidworks, 123D Design. Many of these platforms are free for basic use and there are dozens of available YouTube videos, online tutorials and even online courses through sites like Udemy to provide instructions and user tips. During the Launch Grant, we practiced with Blender as it is a free and relatively easy to use. We found the design process much more difficult than the actual printing. Even with the YouTube videos and online tutorials we found, learning the keystrokes, shortcuts and tricks needed to generate a viable 3D printable model took a significant amount of time. It is much easier to generate models that have polygonal structures, but we ran into trouble figuring out how to create freeform lines and shapes. We explored whether it was possible to import 2D images into the software and then add volume to make it three dimensional, but found that this was not feasible. Christian designed and printed a simple vase, which took approximately 8-10 hours from the time he began learning to use Blender to final print. We are sure that the students’ learning curve would be much less steep than ours, but it still would take a significant amount of class time dedicated to software training and design before an actual print could be accomplished.
Ultimately, we found that printing already available designs was easy and was of great interest to the students. The design process was much more challenging and time consuming than we expected, as we had no prior experience with 3D modeling software. Implementing 3D printing into curriculum would therefore require careful consideration of the amount of time needed to teach students (and the teacher first!) how to use the software, as well as design and print time, vs. the added learning value that the project would bring.