Graphics Reference
In-Depth Information
CAD Software
There are three different kinds of software being used during the 3D printing process. First
there is the 3D design modeling software or CAD (Computer Aided Design) software. After
the object has been designed in form of a digital drawing it is time for the CAM (Computer
Aided Manufacturing) software, which in the case of 3D printing often is called a slicer,
since it prepares the CAD drawing for printing by slicing it into layers. At last there is the
software that controls the 3D printer.
The most important software for 3D printing is the CAD software used in designing and
drawing an object before the actual printing. The finished design is usually saved in an STL
file, a format which was originally developed by 3D systems in the end of the 80s. There are
also many other formats like PLY, OBJ etc. One important aspect for 3D printing is that the
drawn object is “watertight”, since all edges might not be connected although it looks like
that on the screen, there might be holes in the structure etc. Another issue is that size has to
fit in the build chamber, wall thickness cannot go under specified values etc.
The way the software handles and builds geometric shapes are categorized by some differ-
ent terms, for example:
·
Solid
·
NURBS (Non-Uniform Rational Basis Spline)
·
Sculpting
·
Polygonal
·
Parametric
Typical CAD software used by engineers and industrial designers is usually based on Solid
modeling. The solid model is a complete and unambiguous representation of a precisely en-
closed and filled volume. In difference to a simple wireframe drawing all the visible surface
of the object is shown. Solid modeling shows the object as close as possible to the real man-
ufactured product. Solid modeling software includes free programs such as Autodesk 123D,
Sketchup and Tinkercad. These programs are somewhat simpler and easier to learn and more
user-friendly for the beginner. The professional program Solidworks from Dassault Sys-
tems is used by engineers all over the world for precise industrial design, however it comes
with a cost of thousands of dollars. Autodesk's Inventor plays in the same league as Solid-
works. Other popular professional software are PTC Creo (formerly known as ProEngin-
eer), the more complex Catia (from Dassault Systems) and the long runner AutoCAD (from
Autodesk) which originally was a 2D CAD program.
