I have both a 3D printer (which I rarely use) and also a CNC mill and
a CNC router. I use the router for production of parts so it is worth
the huge amount of time it takes to perfect the code to maximize
efficiency of production and to provide good finishes.
As Bernt Damm says, drafting a part is a huge amount of work. 3D
printers are very slow and unless you have a really good one and take
the time to learn how to get good prints, the strength of the parts may
not be very strong. I have successfully made some very strong parts
but it is amazing how complicated it all gets. 3D printing with
consumer quality printers is not easy to do well.
That said, here are some suggestions that may help to get some decent
results without making it an life consuming vocation:
Unless you are already familiar with a CAD program such as Autocad,
choose an easier one to learn. Rhino is much cheaper and much more
intuitive. I can design basic parts in Rhino but am hopeless with
Autocad. You really have to use Autocad daily and probably need to
have formal training or at least a lot of self teaching to get very far
with Autocad.
Designing a 3D printed part involves several steps and the slightest
error such as a gap in the STL mesh will produce horrible results. I
can design basic parts in Rhino and process with a couple of shareware
tools to produce printable STL. There is also a sharing site
(Thingyverse) for sharing STL files as well as customizable things like
little boxes.
There is another possibility and this is the main reason for writing
this letter. It might be possible to photograph and print parts that
do not need to be extremely precise using a method that I have not yet
tried but would like to try. I have a 3D camera on my newest computer.
It is made by Intel. It was not easy to find but Intel has a free
application ['app'] that operates the camera and produces STL files for
printing.
The app has a very useful feature that might make the quick production
of certain types of parts feasible without spending hours drafting in a
CAD program. The 3D photographs are often imperfect with gaps in the
photo. If these are converted to STL a closed solid will not result
and printing will be impossible.
Fortunately the app will automatically make closed solids from an
imperfect 3D photograph. I have tested the process but have not
actually printed anything using this method. I have used various
programs to check the STL files and theoretically the files from the
Intel program should print.
To make a 3D photograph you just need to set the object on a turntable
and rotate it. The Intel program does the work and the results are
quite good if the lighting is done carefully.
One problem for which I have not found a solution is that the program
produces STL files which are triangular meshes. These are fine for
printing but they are very difficult to edit. You can scale the part
in the 3D printer but something as simple as making a shell out of a
solid is very, very difficult.
CAD programs work with NURBS (Non-Uniform Rational Basis Spline) which
allow you to amazing stuff. Unfortunately it is not possible to
automatically convert an STL to a NURBS representation for further
processing. If someone ever figures out how to do this it will make it
possible to edit the models. Or if a camera control program is
developed that produces editable files this would accomplish the same.
That all said, if anyone can think of a suitable player part that I
could take a 3d photo of and print, I am willing to try. It must be
something that needs no editing other than scaling and be small enough
that it will not take forever to print. It is also possible that other
3D scanning systems hove worked out this problem but I have not checked
and do not need any more toys at this point.
Spencer Chase
Garberville, Calif.
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