User manual

12 User Manual
Arduino Materia 101
Before you start printing with your Arduino
Materia 101 it is important to understand how
you arrive at a finished object.
This allows you not only to know what you
need to do to give form and substance
to your ideas, but it helps you to identify
any constraints and limitations of the
technology used by this printer.
In the table (FIg.1, page 17) we summarized
the steps required to obtain a 3D printing.
MODEL
It all starts with creating or downloading a
three-dimensional model of the object that
you want to print in 3D.
The creation is done through one of the
many modeling programs available over the
internet as freeware, shareware or software
for a fee. There are many and each of them
has specific characteristics. In this respect it
is worth noting that you can have different
modeling requirements and this is reflected
in the variety of applications. Some are
more suited to mechanical design, other
artistic modeling, other than architecture.
Remember that 3D modeling was primarily
used to create projects or for rendering.
In the first case the model was thought to
be accomplished physically and therefore
is subject to a series of specifications and
constraints that allow the project to be
turned into something real. In the latter,
the aim is to create an image for certain
requirements: the model might then be
flawless as display but physically impossible
When you choose the program that you want
to use for your models you must then ensure
that it is able to create a file suitable for the
production (especially 3D printing) so those
programs that offer features of rendering or
animation driven.
DOWNLOADING FROM
INTERNET
The net offers many ready-made 3D models,
but also in this case there are differences
between the models that you “see fine” and
those who “print well”.
A good indicator of the ability to print the
pattern is of the form: the most popular
3D printing is STL (sites that intend to
offer printable objects use this format).
If there is no STL it is likely that the
intended use is different and the result
on a 3D printer is not guaranteed.
FROM A 3D MODEL TO
A PRINTING FILE
The real “secret” of three-dimensional
printing is the transformation of three-
dimensional object into a sequence of
two-dimensional slices that overlapping,
reconstruct the object. Imagine a series of
slices of bread: If the stack rebuilt the loaf
from which they were cut. In the case of 3D
printing every slice may consist of two-
dimensional shapes not connected together
as it is their sum to create the finished object.
Thanks to this breakdown, the object can be
complex as desired because the printer will
draw with the plastic one layer after another
without overlap; a square or a doodle for the
printer have the same difficulty.
The most important work the software
makes is starting from the 3D model –
usually a mesh of triangles in space called
mesh and transforms it into a sequence of
slices according to a number of parameters
(slicing). Because the process is completed
correctly the mesh should be closed and not
have triangles that are oriented incorrectly
confusing the “inside” and “outside”. It
happens that some model is not made to
art: at this point or the software that does
the slicing manages to repair the mesh
or the result of errors that will prevent
the correct reproduction of the object.
A GOOD STL,
A GOOD SLICING,
A GOOD PRINT
The STL file is the starting point for
the entire procedure, so from the file
should be removed anything you don’t
want to print (hidden objects, etc.).
The 3D drawing must be a solid and not
a solid sum interpenetrate or match.
Similarly, the design must be as clean and
precise as possible: articles must have an
inside and an outside well defined so that
the surfaces perfectly match each other
without leaving holes. most 3D design
software gives you the possibility to carry
out an analysis of borders to check for
holes.
The 3D drawing must be oriented in
such a way as to have a face adjacent
to the XY plane of your drawing
software: in other words, the design
should not “float in a vacuum”,
otherwise the machine will not print.
If you’re working on a STL downloaded
from internet or given to you by a client,
there are free software for checking and
correction of STL as Netfabb. The “slices”
are printed in a specific format (called
G-Code); This format is nothing more
than a set of instructions for moving
the instrument (cutter, laser or extruder
head) along a path X, Y, and Z axes.