3D Printing STEM Projects and Information
3D printing has become
very affordable and there is a lot of mathematics that can be learned when designing
projects. The plastic of choice for schools is PLA which is actually a corn
starch but also a very good building material and lasts for a few years. The
choice of printers is large now and in the beginners or entry range are some
quality well priced machines. Do your homework here, ask around.
My printer is an
Aquila X2 made by Voxel Lab
and supplied by MakerShop
in Auckland. I chose this one because of the $400 price, the reports were
excellent and I could buy it here in NZ. It was delivered a few days after
ordering and I was so impressed after printing a few jobs I bought another
which remains unpacked under the bench. I bought a variety of PLA colours and
some ABS to experiment with as well. No other spare parts needed yet. It comes
with a printhead nozzle cleaner and assembly tools.
Assembling the printer
was quite straightforward but I also looked on the internet for Assembling the Aquila X2.
The link takes you to a Utube presentation on
building and levelling the printer. An invaluable help. There are several
versions.
HINT – If you
are in a school build this printer with a couple of tech-handy students. You
are going to need a techie just to keep an eye on and help out with
“levelling”, “loading”, unloading”, “plastic jams”, “general care” and “a go-to
person”. Keep it covered when not in use and use it on a solid bench to
eliminate vibration and bumps. Train a 3D Printer Student.
Levelling the print bed is
important. The heated bed the print is made on is about 0.2mm below the print
head. The print head moves in a level plane and the bed is adjusted using twist
screws on the four corners. A piece of A4 paper is used to just grab the print
head and so create a constant gap across the bed. See the utube
vide. I spent 30 minutes convincing myself the level was correct and have only
readjusted it once more in 6 months. This printer has an offset adjustment as
well to raise and lower the print head 0.1mm at a time.
Using the 3D Printer
Step Zero – Have a small project in
Mind.
Step One is Designing whatever
you might want to make. I like math puzzle models so my first projects were to
design the Soma Cube, Maltese Cross, Pentominoes and a Packing Problem. This
was done on CAD software.
Tinker
CAD
is free and an excellent first choice introduction to 3D design. It is intuitive
to use and learn.
Here is a screenshot of the home
screen and one of the work space showing my Maltese Cross design. Tinker CAD is
based on AUTODESK which is one of the standards of professional 3D design. Good
future proofing for careers!
Once designed the file is exported
to your computer in .STL format. Here
is an example. This is the icon for my Maltese Cross in the picture above.
Step Two is the SLICING SOFTWARE – This comes
with the printer and is the software that looks at the .STL file and creates a
series of layers that build up the 3d print. The print head prints each layer,
one by one, to build up the final model. The slicing software is CURA and is free. No
need to download as it all comes on the little SIMM that comes with the
printer.
This is the
35th slice out of 50 in total and shows the internal structure.
The fill and fill pattern can be changed,
a raft can be added as shown. I use a raft to build the model on so that I have
flat edges on the bottom layer. One of the many things I learned. I had to hand
file my early models! The adjustments that can be made to the print file are
many and I will leave that to you to discover.
Step Three - TRANSFERING THE FILE TO
THE PRINTER – This had me puzzled. It does have a USB port which I have
never used. My Mac has a Micro-SD port and so does the printer. Job done.
Insert the Micro-SD and it just appears on the desktop of the computer like a
Data-stick and drag and drop the file to the Micro-SD card. Eject from the Mac
and inset into the printer. Select PRINT, select the file and everything starts
to happen. The plate heats up, the print head heats up and then when it is at
temperature the printer moves and prints.
LOADING and CHANGING PLA – The Aquila has a control screen and
Automatic Load and Unload can be selected. This is really easy to use. I did
break the PLA filament a couple of times by leaving it too long in the printer
or letting it dry out or something. That required figuring out how to extract
broken pieces. Not hard and it reloaded easily. Hint is when finished a print
“Auto Unload”. It is easy enough to load it again.
MAINTENANCE - I asked Mike
at MakerShop if there is any maintenance and he
replied -
Hi Jim,
I'm glad to hear that you are having such a great
success with your printer. We'll be getting more, but for the moment we're out
of stock. Better get onto that if you're promoting them for us.
There's no
specific maintenance that I would recommend. Just generally keeping them
clean. Removing dust. Avoid storing it in a damp place.
Keep an
eye on the filament drive roller. If the teeth become clogged then clean them
out with a pin or a blade.
The filament tube and the nozzle are the parts
that may need to be replaced eventually. We usually have these in stock.
Perhaps more important is keeping your filament
dry. Any opened filament rolls are best be stored in a sealed container
with some desiccant and you should reactivate the desiccant periodically by
baking out any moisture. You'll get better print quality and fewer print
failures with dry filament.
Regularly
wiping down the print bed with alcohol (ethanol, methylated spirits or IPA)
will help with adhesion. It removes the oils that comes from touching it
with your hands.
Regards,
Mike
I would add to keep an eye on the
drive belts which must stretch after a while. Just tighten a tinch every so often. Check the bolts are all tight on the
frame. The fans and motors will eventually wear out but after thousands of
hours. Mike has spares.
Starter Projects – The design is the
learning with STEM.
This is also from Mike at MakerSHOP.
One of the messages I would like educators to
understand is that learning to use a 3D printer is not the goal here. The goal
should always be to get students excited about design and problem
solving. The 3D printer enables students to turn their designs into
something tangible and functional and helps to motivate students to learn new
skills in design.
Tinker cad is a great starting platform. From
there you might want to look at Fusion 360 or Onshape.
Both are free for non-commercial use and have ready-made course materials for
educators.
#1 Packing Problem. See Picture 1 below. The six 2x2x1 (cm) blocks
which will fit in a 3x3x3 box and the lid will fit on top to keep it all tidy.
It is an easy project to design with some interesting measurement tolerances
that have to be estimated so everything fits. It is also an interesting puzzle
to solve. A bit of fun.
Picture 1.
More starter projects coming.
2/2/23