Hi Deirdre;
When you use 3d software, you’re making a model, not just a drawing.
It’s important to make the transition mentally, to start thinking in
three dimensions. The sort of software to get depends to a large
extent on the type of jewelry you wish to make. It’s perfectly
possible to use 2d software to design jewelry, of course - you can
produce vector graphics, for instance, and use them as masters for a
photo-etching process. But when you make the leap to 3d, a 2d drawing
is just a single view of the object you’re building; the model is
something you can look at it from any direction.
There are a few different approaches possible when designing jewelry
using a computer. There are programs that are specifically tailored
to jewelry design, that assume you’re going to be making one of
various standard sorts of things - rings, say, or Tiffany-style
heads. They usually have libraries of stone shapes, and range from
something that a salesperson can use to quickly match a customer
with a certain size stone in the right size setting, to powerful
programs that allow a skilled modeler to create nearly anything that
comes to mind. But jewelry-specific programs tend to be more
expensive (or a lot more expensive) than general-purpose programs
that can do the same basic things.
It is also possible to create jewelry in programs that were designed
for general-purpose modeling. There are many programs available that
can be used. The primary requirement is that they be able to generate
a STL file; this format was developed for data exchange into additive
Rapid Prototyping (RP) systems, which build up a part by depositing
successive layers of material. It’s also used by CAM (Computer Aided
Machining) programs, which translate models into toolpaths a
computer-controlled mill can execute, to carve the model from a block
of material. There are other output formats as well, but STL seems to
be the most generally accepted and least problematic.
Asked for my recommendation a few months ago, I would have had to
suggest you buy several separate programs, but just lately they have
been coalescing into a single offering. Rhinoceros is an extremely
powerful but simple-to-use 3d modeler which uses splines (aka NURBS)
as the basic structure for making surfaces that are lightweight (so
the computer doesn’t bog down) and infinitely scalable. It excels at
making smooth, dimensionally accurate compound-curved surface models,
but isn’t very well-suited for subtle sculpting of organic details.
The Omni arm and Claytools software from Sensable Technologies, on
the other hand, is perfect for that. This system includes an
articulated arm device with force-feedback, which allows a user to
actually feel a virtual 3d model as it’s being worked on, and a set
of software tools that enable carving, smudging, tugging, smoothing,
and embossing and stippling with 2d art, as well as a number of other
functions. Using it is as close as a digital modeler can come to
actually using a real tool on real material - with some advantages,
like Ctrl-Z undo, and the ability to work from the inside of a form,
that aren’t available in the real world. This has now been made
available as Claytools for Rhino, which gives one the benefit of both
types of modeling in a single reasonably-priced bundle.
Once you have a digital 3d model, you can choose from a range of
processes to generate an actual part. The RP system most jewelers
prefer is made by Solidscape; it’s an expensive and touchy machine
but gives excellent surface detail, part configurations can be just
about whatever one wishes (as long as the model is totally solid),
and it prints 3d parts in a waxy material that burns out well. There
are a number of service bureaus that use them, and the price per
model is generally competitive with hand-carving. The other
alternative is CNC (Computer Numeric Controlled) milling. This
involves using a 3, 4, or 5-axis milling machine fitted with stepper
or servo motors which can replicate a 3d model by removing material
using rotary cutting tools. This requires running the model through
a CAM program and making some choices about tool size, feeds and
speeds, fineness of cut, etc. Part configurations are more
restricted, since the tool has to be able to reach the surfaces, or
they won’t be cut. But CNC machines are much less expensive than
additive RP machines, and a great variety of materials (wax,
plastic, wood, bone, stone, metals) can be cut, given the correct
machine and tooling. If you wanted to go this route, VisualMill, a
very powerful CAM program, has just been incorporated into Rhinoceros
as a plug-in (RhinoCAM Pro), and it’s being offered at a special
introductory price, so you could get all the software you need in a
single bundle.
Andrew Werby
Scanning, Modeling, and Milling Products at Discount Prices