Model-Making An Ancient Art Steps into the 90’s

Is model-making in the jewelry industry a vanishing art or an emerging science ? The answer varies depending on which industry segment you explore. The rapid development of technology to handle many parts of tool and die creation has, in many cases, replaced skilled toolmakers and modelmakers with trained technicians operating complex machinery . Casting, whether involving wax, white metal or the newer plastic resin models, still requires modelmakers with keen eyes and precise hands. Yet even in this area, new technologies are making in- roads on t-he ways in which models for jewelry can be produced faster and more efficiently. There are newer laser and CAD/CAM (Computer-Aided Design/Computer-Aided Manufacturing) technologies in the pipeline right now that could eventually change the entire process of modelmaking for both die stamping and casting as we know it today.

To get an overview of the state of the art in model-making today, AJM surveyed a number of industry experts and observers.

Die Stamping and Making Tools

For most of the larger companies working with tools and die stamping, electronic equipment has taken the place of hand workers, except in some cases where older tools or dies are being revamped, or prototypes for unusual decorative findings need to be produced manually.

Michael Salvadore Jr., president of the Metal Findings Manufacturers Association, outlines the current state of the art in this area.

“With the new machines like Electronic Discharge Machines (EDMs) to handle die cutting and die sinking, one-to-one duplicating mills, wire sinking equipment and other advances, for many manufacturers it’s become hardly worthwhile to train modelmakers,” he says. “Apprenticeship programs for hub and die makers take six years on average, and are few and far between. Meanwhile, with the electronic systems, all you need is a technician who can set up the machines, then monitor the system while it does the work. EDM has become the science as far as die sinking is concerned.”

Eddie Bell, vice president of Rio Grande Albuquerque in Albuquerque, NM, a major supplier of tools and supplies for the jewelry industry, further explains the growing popularity of the technology.

“The prices of CAD/CAM systems for jewelry design and model production have decreased dramatically in the last few years,” he notes. “These days, the bottom of the CAD/CAM lines, which are still highly powerful machines, are competitively priced with top of the line personal computers. There is still a real need for good designers and modelmakers in the smaller companies who don’t choose to work with the new electronics. And there will probably always be a need for specialists who can use machine tools to make models for new tooling, and modelmakers in any area who know how jewelry is produced, have fresh ideas for jewelry fashions or tooling, and know how to make those ideas practical and producible.”

Robert Dufault, owner of Andre’s of Lincolnshire in Lincolnshire, IL, is a retailer, manufacturer and computer software developer in the jewelry industry. He has set up a number of cost-effective electronic systems to handle milling, modelmaking for both casting and stamping, and high-precision inlay work and precision fitting operations based on combining computerized CAD/CAM systems with laser technology .

He advises smaller manufacturers thinking of installing computerized systems that while a PC-based system can handle many design and modeling functions, “right now, the CAD/CAM software for PCs isn’t yet user-friendly and sophisticated enough to handle much of the threedimensional work needed for designing and modeling jewelry. We can do 3-D milling on three axes on gold, silver or wax with high precision for geometric shapes or flat objects, but not free-forms,” Dufault says. “There is technology in place, like laser-based stereolithography, to handle three-dimensional modelmaking, but right now it’s simply not feasible for most manufacturers because of costs involved.”

Casting

The ancient art of making models for casting has been a mainstay of the jewelry industry since the dawn of recorded history. The development over the last century of tools like the flexible shaft machine, rotary polishers and electric casting equipment has served more to speed up the process of model-making than to replace modelmakers. In this segment of the industry, skilled modelmakers are highly valued, though becoming harder to find outside of major jewelry centers.

What does it take to be a good modelmaker? The composite portrait of the “ideal” modelmaker, cited by our respondents, includes: strong artistic sensibility, preferably with a sculptural approach; the ability to translate two-dimensional ideas on paper into three-dimensional, wearable and producible ideas in wax, white metal, plaster, and even clay or resins; an understanding of sprueing, investing, mold-making, and the other processes by which casting is done.

Also: a keen eye for surface flaws on the model that might later cause pitting or rough surfaces requiring hand finishing; steady hands with high manual dexterity; the ability to stay calm and work patiently under tight deadlines and stressful conditions; an ability to visualize how a given piece of jewelry for which the model is being made will fit around the human body; the knowledge of what can and cannot be cast durably in metals; and background (optional) in jewelry history .

The respondents also agree that there is not yet enough formal training for young modelmakers entering the industry. Jewelry arts programs are available at colleges such as the Rhode Island School of Design; Fashion Institute of Technology and Parsons School of Design (both in New York City), the Revere Academy of Jewelry Arts in San Francisco, Highline College in Washington state, Paris Junior College in Paris, TX, and others, as well as through the Gemological Institute of America. Most, however, do not have a comprehensive program for modelmakers that includes handson apprenticeships over more than one year in the industry alternated with classroom time.

Eddie Bell cites the concern of his manufacturing clients in the search for skilled modelmakers. “If the jewelry industry is serious about being a viable industry 10 years from now, we need to have highly skilled labor . We need more jewelry programs which turn out modelmakers who know as much about production economics, jewelry engineering and manufacturing processes, and new technologies as they do about carving, design and finishing models.”

New Technologies

In casting, the cutting edge of technology for making models involves working with light. For the past few years, Kerr Manufacturing Co. of Romulus, MI, has been selling an inexpensive “Customiser” model-making system that can produce models and molds made of special plastics that fit into a series of mold frames provided, of which the largest is 65mm (W) x 140mm (L) x 13mm (H), in about 10 minutes. This system takes a two-dimensional flat drawing, and exposes it to light to develop a negative, from which a three-dimensional flat model of either one millimeter or two millimeters thick is made by curing the resin. The photographic nature of the process allows fine detailing of complex patterns, and produces the model within 10 minutes. The mold then takes another 10 minutes to produce.

Perhaps the most exciting new developments, however, are in the area of three-dimensional modeling with lasers and computers. This process (mentioned earlier) is called stereolithography, and combines computers with lasers. Instead of having a milling machine with a tool path, the -stereolithic system has a tank of clear liquid resin through which a machine laser is directed. The light hardens the resin into microscopic beads of resin by millionths of inches, to build up and create a holographic plastic model of the design programmed into the computer. The model can then be invested and burned out like wax.

Bob Dufault has worked with the new stereolithic systems, and says there are still some major problems that need to be worked out before it becomes practical for making production models. “For one thing, the surface of a stereolithographic model is not microfinished. It’s like orange peel, and needs extensive hand finishing. For another, the machinery for the resin bath is very expensive, the software is not available in any easy-to-use format, and the system as a whole is slow. It might take the machine two full days to make what an expert modelmaker can carve in 15 minutes.”

Will all this machinery replace human modelmakers? The consensus among respondents in the casting segment is a resounding “no.” However, it is generally agreed that tomorrow’s modelmakers will need to have good training available to them, in both production and the more common benchworking tools and technology, simply to master the new equipment becoming available that can help them do their jobs more efficiently.

Advice to manufacturers seeking good modelmakers includes; Advertise in trade magazines, crafts publications and vocational school publications around the country; go to crafts fairs to see who is making precise sculptural jewelry there; look for universities with good art departments that have degrees in art and/or jewelry making, then hire graduates and train them in your own methods; start or support an apprenticeship program in your own region for model makers and designers; and even look at the work of sculptors in your area.

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