Wax Works

By casting diamond jewelry with stones already set, US manufacturers save not only time and money but also sales.

No one bothered to tell department store quality inspector Bill Hoefer about the secret new weapon that American jewelry makers are counting on to stem the tide of business lost to Asia. He just stumbled on its existence by accident. “I was louping a tennis bracelet for defects and I noticed that a couple of stones had gold-Iined gletzen [fractures also known as feathers],” the San Jose, Calif., gemologist/appraiser recounts. “‘How can this be?’ I asked myself. Then I realized the piece must have been cast in gold with the diamonds already set and that some of the metal must have been injected into surfacebreaking cracks.”

It took a few seconds for the full impact of this discovery to register. Somehow or other, Hoefer realized, manufacturers had learned to set stones prior to casting. This meant they no longer waited to mount the stones until after casting metal mountings-a much more time-consuming and expensive process.

Hoefer had his revelation just before Christmas 1994, when this revolutionary new technique-usually called “casting in place” or “wax setting”-was used mainly in India. A year later, however, Hoefer found it had also become a common feature of American-made melee diamond jewelry.

What’s more, manyofthe companies that practice the technique evidently have improved their proficiency with it almost overnight. Indeed, when asked to provide a poorly made piece with diamonds that had been set in wax prior to being cast in gold, Hoefer could not produce a single one for us to photograph. “You should have asked me a year ago, when I was finding lots of reject jewelry pieces with stones cast in place,” he says.

Today casting in place is no longer a secret. “Nearly everyone of our customers is requesting it, ” says a New York-based Indian jewelry manufacturer who makes jewelry on a contract basis for many large retailers. But what still remains top secret is the method and how manufacturers are mastering it so swiftly. As the Indian manufacturer notes, “People ask for it without really knowing what it is.” Among those people are jewelry manufacturers themselves.

To make sure they learn casting in place as quickly as possible, many companies are hiring metallurgists with jewelry backgrounds to equip and train them. One such metallurgist, Timo Santala of Touchstone Metals, Providence, R.I., has already brought a dozen New York and Los Angeles factories up to snuff when it comes to casting in place. One of Santala’s New York clients, Abba Creations, recently permitted Modem Jeweler to photograph the technique up close.

“By the end of 1996,” predict Abba President Abe Arev, American companies that make diamond jewelry will be setting at least some stones in wax. one of the best ways for this country to recapture its comlpete tive edge.” So it would seem. Here, with the help of Santala and Arev, is a guided glimpsE the technique.

For more than 40 years, casting has been the predominant means of jewelry manufacturing, especially of gold jewelry set with diamonds and colored stones. Put simply, casting involves making jewelry items by injecting molten metal – usually gold or sterling silver – into hollow molds that originally housed master models used as patterns for the molds. Until about 1990, it was standard operating procedure to cast a head or mounting without seats for stones cut in it. The last step in the gemstone jewelry manufacturing process was usually reserved for specialists, who cut seats individually and then set stones in them.

As America started losing tell business to Asia, where cheap labor rates made it far less expensive to produce multiple-stone jewelry, U.S. manufacturers suddenly had to seek ways to keep their share of this once-lucrative business. Yet the fight to stay competitive seemed a losing battle–the cost of setting popular but problematic baguette diamonds was as high as $2.50 for each stone. (Round stones were far cheaper to set.) Short of forcing American setters to work for Asian wages, U.S. manufacturers would have to find ways to bypass traditional setters and setting methods. Just the savings of a dollar or two on a generic piece of jewelry in today’s price-conscious jewelry market could mean the difference between writing and losing orders.

The most promising possibility for new economy in multiple-stone jewelry making was modifying the casting process itself. If stones could be set before instead of after a mounting was made, manufacturers could pass on time and labor savings by significantly lowering prices. But how could the process be changed to allow stones to be set before casting?

The answer: Find a way to set stones in the wax model of a piece. (A wax model is used to translate the original design, which is represented by a silver model, into the finished gold piece.) The cost advantages of setting in the softer medium of wax were obvious at once-setting diamonds in wax is at least 50% cheaper than setting stones in metal. But to succeed at wax setting without damage to stones, manufacturers would have to exert more control than ever before over every stage of the casting process. That’s why Abba Creations hired Santala, whose background included stints at Leach & Garner, North Attleboro, Mass., and Stuller, Lafayette, La., among other companies, to gear up its factory for the change to casting in place. “We spent eight months experimenting with the new process before we were ready to start offering it to the trade,” says Arev. Last fall Abba began billing itself as a practitioner of the new technology and offering its services in wax setting to jewelers and other manufacturers. It undoubtedly will be followed this year by many competitors. Ironically, Abba’s Indian counterparts had already beaten the company to the punch by introducing wax setting as much as two years earlier. Perhaps some Americans were also toying with the new technology. However, many of the first wave evidently introduced the technique prematurely. That’s why Hoefer found so many gold-filled diamonds in the pieces of jewelry he inspected for various clients.

For wax setting to be successful, stage one of the casting process-preparation of a silver master model-must be perfect in every detail. Unlike conventional models, this one will be made with seats for the stones already cut into prongs or channels. The model maker must think as a setter does and check crucial criteria such as seat thickness and alignment with other seats. If a seat is cut too deep or is much higher or lower than other seats, the finished piece will be less durable and may have appearance problems.

Once the silver model has been completed and approved, it is packed tightly in vulcanized rubber, where it leaves an exact impression. Then the silver model is removed, leaving a reverse-detail hollow mold into which liquid wax will be injected. After the wax has cooled, it will serve as a model for the final gold article.

It is at this point that wax setting deviates from conventional casting a second time. Ordinarily, manufacturers take a grouping (called a “tree”) of wax models and embed it in what is called “investment” (a plaster of Paris-like material that contains special additives to make it heat resistant) inside a special flask. Next, the wax is burned out, leaving a series of full-relief imprints in the investment material. These imprints eventually will be filled with molten gold. Once the metal has cooled, the gold articles are retrieved from the flask and sent for setting and finishing.

Casting in place, however, requires one additional step between the creation of a wax model and its placement (along with other wax models) in the flask for burnout: setting of the stones in wax. Because wax is so much softer than gold, setting takes only half the time it does in metal. Even so, setting stones in wax requires the development of an even softer touch than is needed to set stones in gold. That’s why getting the hang of wax setting takes special training. Indeed, skill at setting stones in gold does not necessarily guarantee an instant aptitude for setting stones in wax. “You must understand wax and working in wax,” says Arev.

To be frank, at this point in time learning to work in wax is not a skill traditional setters wish to develop because the mass adoption of this technique by domestic jewelry manufacturers threatens them. And well it should. Wax setters are paid far less for each stone than precious-metal setters – especially for baguette work. Yet jewelry manufacturers say that they have no choice but to convert to lower-paying wax setting if they want to keep or regain sales of mass-market multiple-stone melee diamond jewelry styles, which have become mainstays of manufacturing in India, Hong Kong and Thailand during the past decade. It’s a Catch-22.

Nevertheless, traditional setters need not fear obsolescence as manufacturers rely on wax setting for pieces with increasingly larger stones. So far, the technique has been-and will most likely continue to be-reserved for melee goods, for both technical and economic reasons. “Because of the high temperatures involved in casting,” Santala explains, “there is always a danger of ‘frosting’ [bumingl stones. That’s why I do not recommend setting stones over 1;4 carat in wax.”

Even without the danger of blacken- ing diamonds, it is doubtful that many manufacturers will begin to set larger diamonds in wax. The cost differential between setting stones in gold and in wax is too insignificant to warrant it, especially with finer stones that require setting in pieces with immaculate finishes. Such fastidious results are not yet possible for pieces with stones that have been cast in place. “Wax setting is mostly for low-end jewelry,” says the Indian manufacturer. “The people who demand it are much more interested in price points than in excellence.”

Will wax-setting technology advance to the point that all cast jewelry with diamonds can be made using it? It’s highly improbable. But casting in place is still an evolving technology, and attitudes toward it are growing more and more favorable. A case in point: When we interviewed the Indian manufacturer last summer about wax setting, he expressed a low opinion of it and dismissed its relevance for him. Six months later, his factory was gearing up for the technique and he was offering it to any American clients who wanted it. “Our workers have made such strides with wax casting that it would be foolish to deny its many cost advantages to retailers,” he says.

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