Digital Designs and Scientific Hardware - Open-Source Lab: How to Build Your Own Hardware and Reduce Research Costs - page 186

Reprap extruder nozzle has a 2 mm minimum feature size, 0.1 mm positioning accuracy, and
a layer of 0.2 mm thickness. There has already been considerable work done to move to smal-
ler filament diameters and nozzle sizes, which have, for example, pushed the step height to
0.1 mm (100 μm), but extremely high tolerances are still not accessible to low-cost open-source
3-D printers. This will unquestionably change in the near future, but that does not help you
now if this is needed for your project tomorrow.
In the same way, the Arduino platform is meant primarily for prototyping so microcontrol-
ler boards designed for a speciic purpose can have beter performance or have properties not
available currently (e.g. able to handle higher voltage ranges). The Arduino platform is also
costlier than just using the microcontroller chip itself, so there are always considerable cost
savings from making a specialized board for a specific application such as the Melzi board
discussed for the RepRap in Chapter 5 . Third, in general, there are no warranties associ- ated
with open-source optics equipment—the users get what they make. Thus the quality of the
components and the work that can be done are sometimes user dependent. For example, parts
printed from acrylonitrile-butadiene-styrene (ABS), the same polymer that makes up Lego
blocks, are relatively robust if printed with sufficient fill. However, the mechanical strength
of the components is dependent on the quality of the print, which will vary among print-
ers/users. Further work is needed to determine if the layered material can endure consistent
rough manipulations in educational applications (e.g. the purposefully destructive beatings
equipment can take in public schools) so the lifetimes of printed parts can be compared to
industrial-manufactured injection-molded components or those made in more robust materi-
als such as steel. Finally, although the sharing of open-source optics designs significantly re-
duces the complexity of replicating equipment, there are still substantial knowledge sets ne-
cessary to take full advantage of the power offered by the open-source approach. These know-
ledge sets can act as barriers to entry for researchers and educators. For example, the software
knowledge necessary to operate OpenSCAD, the printing software, and the Arduino coding is
largely dependent on prior exposure to and basic programming ability and skills of the user.
The more experience you already have in these realms can be leveraged to quickly complete
highly advanced projects to develop scientific tools. Not all groups are necessarily as well en-
dowed as some of the example labs we highlight throughout this topic. However, there are a
vast array of free online tutorials, videos, examples and instructional materials available for
the novice users for all three types of software. In addition, there is work by our group and
others (e.g. the entire education system of the Netherlands) to assist young students gain dir-
ect exposure to open-source 3-D printing and Arduino programming. As these students climb
up the ranks of academia, they will represent an enormous wealth of super user/developers
to accelerate the evolution of scientific equipment and science itself in both academic and in-
dustry labs.
Future work on the technological development of this open-source optics model is neces-
sary to meet the full potential of the concept. Although 3-D rapid prototyping is currently used
primarily in research and development and thus contributes only to a tiny fraction of global
manufacturing, the process has an enormous potential to fabricate more complex components
with improved precision and materials selection. RepRap-like printers need to be developed
that can print other materials with sufficient resolution to produce lenses, filters, mirrors, and
other both optics and nonoptics equipment in the physics lab. With advanced deposition tech-
niques, chemically active components and optical coatings could be printed. Thus mirrors and
filters, with different wavelength ranges could be custom digitally fabricated by simply depos-
iting desired species. In addition, 3-D printers in the future are expected to have higher resolu-
tions, which enable other applications. Taken to the atomic limits, 3-D printing can be applied