Before I could start slinging plastic filament, however, I had to solve two design problems: First of all, I needed a rock-solid building material that could be easily assembled with simple hand tools. Secondly,
I had to find a professional-grade 3D design tool that would
enable me to draft a construction plan for my upcoming 3D
printer. An advertisement in SERVO Magazine solved my
first problem, while a wee speck of serendipity gave me a
design tool solution.
An Actobotics™magazine blurb convinced me that this
was the perfect building system for turning a 2D design
into a 3D reality. While I was skeptical about the real world
impact of an “intuitive design [which] makes building easy
for both the experienced engineer and novice hobbyist,” it
was the system’s matching aluminum channel components,
overlapping hole patterns, and tight tolerances — all of
which were supported by a large library of 3D computer-aided design (CAD) files which helped to clinch the deal.
Lucky for me, there were two unusual files tucked away
inside a compressed file that accompanied the assembly
manual for my failed 3D printer kit. One file was a STEP
(ISO 3D CAD file format) converter for handling all of the
Actobotics 3D files, and the other was Autodesk 123D
Design. Within one hour, I had downloaded an enormous
collection of Actobotics’ STEP files, converted them to
Autodesk-readable OBJ files, and was moving pieces and
parts around on a monitor trying to create a plan for a new
3D printer concept. You can see this concept slowing
emerging in Figure 1.
In less than one week, DUPe1 was born — or, Dave’s
Unorthodox Printer experimental version 1. What makes
this printer unorthodox? Well, first of all, there is no
extruder, thermistor, or hot end! These three big typical 3D
printer stumbling blocks are all handled by incorporating a
3Doodler™into the design. Yes, there are certain
(i.e., proprietary filament, constant filament replacement,
two hour operation ceiling), but the elimination of filament
feed issues, bulky filament spools, and hot end clogging
help to minimize these minor annoyances.
(In case you’re wondering, that’s “dupe” as in a noun
or verb meaning “duplicate;” not “dupe” as in the verb
tense to “cheat, trick, or hoax!”)
Other features that make this 3D printer design
unorthodox include: a Z axis trolley that moves with gravity
assist; an X-Y axis trolley that is driven by a gorgeous rack
and pinion gear system; and the use of three small low cost
stepper motors.
One thing that isn’t unorthodox, however, is the
lightweight rock solid platform that was made from
Actobotics aluminum channel. This space-age metal system
is easy to assemble and remarkably interchangeable with
numerous options for solving any design challenge.
On a hot summer night, I built my first 3D printer. It was a no-name, low
priced kit that provided me with a solid understanding of 3D printer
components, but not much else. The resulting prints were poor, and within
three hours of operation, the Y axis stepper motor had failed. Shortly after
this failure, I began planning my own 3D printer design.
By Dave Prochnow
SERVO 05.2015 55
Post comments on this section and find any associated files and/or downloads at
www.servomagazine.com/index.php/magazine/article/may2015_Prochnow.
Figure 1. Designing DUPe1 in Autodesk 123D Design.
More Extrusion
For practical applications for using your 3D printer, check out
Chuck Hellebuyck's “Practical 3D Printing” column in Nuts & Volts
( www.nutsvolts.com).
