Precious Metals & Bench: Metalsmithing
The CAD/CAM Revolution
Now within reach of custom-jewelry designers who work in
jewelry stores, this equipment can save time and build business
The jewelry industry is keenly aware of the profound effect
diverse technology will have on its future. One technology destined
to cause a revolution is CAD/CAM, which stands for computer-aided
design/ computer aided-manufacturing.
Thought of most often in connection with large-scale production,
CAD/CAM also allows smaller-production designers and jewelry
manufacturers to provide unique designs at mass-production prices.
The greatest cost of a one-of-a-kind piece or small production
run is the labor in creating and perfecting the original model.
Traditionally, someone hand-carves a wax model or painstakingly
fabricates a white metal model. Once the model is made, its cost
is spread out over the number of pieces that will be made from
it; for example, larger runs are more profitable than small ones
because the cost of making the model is spread over more pieces.
The expense of models lies mostly in the time it takes to
make them. It takes three to 10 hours to carve a good-quality
wax model for a single custom piece or small production run and
up to 50 hours for a model used in large-scale manufacturing.
The difference arises because the custom jeweler stops adjusting
the wax model at a certain point; even if a small problem remains
in the model, the jewelry can be fixed once it's cast. Large-scale
manufacturers, however, scrap any flawed copies and start over
because it would be too costly to correct flaws in the mass-production
Enter Rapid Prototyping
Rapid prototyping refers to the creation of a three-dimensional
model that can be evaluated during manufacturing before tooling.
Some of these technologies are laser-driven and others are CNC-based
(computer numerical control, otherwise referred to as 3, 4 and
5 axis milling).
After creating a design using CAD programs, I use the Sanders
ModelMaker-II to make my models. This machine has the finest
surface resolution in rapid prototyping and produces combustible
models. The models can be investment-cast, which fits naturally
in jewelry manufacturing.
The virtual models created in CAD programs can be downloaded
to the ModelMaker-II for manufacturing. A proprietary technology
slices the virtual models in a process called sterolithography.
Once the files are sliced, the ModelMaker-II uses inkjet technology
to print each layer in a plasticized wax. Once one layer is complete,
the table drops down and the next layer is printed on top of
There are two waxes: green wax for the model and red wax that
supports overhanging geometries and is dissolved once the model
The build can comprise any combination of pieces. Building
a single ring can take five to 13 hours, depending on how thick
you make your slices. The thinner the slice, the finer the surface
quality and the longer a piece takes.
Economies of Time
If the machine takes as long to make a model as a human modelmaker,
where are the savings? Usually, a single ring isn't built alone.
A build with 10 rings can take 35 to 70 hours, but the machine
can work 24 hours a day while a craftsman goes home after eight.
You also gain consistency and the ability to create variations
on a theme. And you can design free from the constraints of conventional
reduction-based modelmaking. Instead of reducing a solid block
of wax, the models are built so you can achieve geometries once
This technology isn't cheap the entire setup can run
$75,000, not including training on modeling using CAD. But consider
- Assume a three-year life of the machine. At $25,000 per year
plus $30,000 to hire a CAD designer who can run the machine,
you have the custom-manufacturing capability to produce new lines
of jewelry continuously. The time to market is weeks instead
- Custom work and small-run production can be priced competitively
with mass-produced pieces. Of course, mass producers also have
this technology, but if price isn't a factor, superior design
will win the day.
- Small creative jewelers can markedly increase productive
output. Jewelers also can design in lower price points, which
used to be difficult because the jewelry's price had to include
the cost of making the model.
- Increased custom design work using CAD/CAM will individualize
an independent jewelers' business, fight branded goods and compete
against Internet sales of generic jewelry.
CAD/CAM requires an investment in money and effort. It won't
create designs for you and can't distinguish good-quality jewelry
CAD operators most likely will be goldsmiths or jewelry designers
who already understand such factors as necessary wall thickness
or structural integrity of various prong lengths.
It's unknown whether independent jewelers will pool CAD/CAM
resources or whether small manufacturers will offer more cost-effective
custom-design services. For example, your staff could learn CAD
and then send individual jobs to service bureaus running a ModelMaker-II
on a per-piece basis. However, all successful jewelry sellers
will have to have some access to this technology in the future.
Imagine the increased productivity of the goldsmith at the
dawn of the 20th century with the invention of bottled gas and
the flexible-shaft machine. Now imagine being the only jeweler
trying to make jewelry without them! That's how profound CAD/CAM
will be. For now, the early adopters can ensure their place in
the rapidly changing industry architecture. Later, CAD/CAM will
be just one more tool in the arsenal of the successful jeweler.
By Steven Pollack
Goldsmith Steven Pollack owns The Missing Link, a custom-jewelry
studio in Glencoe, IL. His school, XYZ Academy, offers on-line
classes in 3-D solid modeling using CAD for direct production
of wax models using the Sanders ModelMakerII Rapid Prototyper.
Contact him at (888) 300-8031, www.xyzacademy.com.
|Finished pieces the author created using CAD/CAM
|A CAD/CAM wax, cast and finished piece, prepared
by Sanders Prototype, maker of the ModelMaker-II.
||The ModelMaker-II is now used for computer-aided
manufacture in more than 100 jewelry companies, including the
author's. Though its cost is high ($66,900), manufacturer Sanders
Prototype offers a 60-month lease and says the system pays for
itself over time. Sanders Prototype Inc., Merrimack, NH; (603)
Copyright © 1999 by Bond Communications.