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.
