Revo540

But RP systems aren’t for everyone. Service bureau owner Ted Karl of Ted Karl Designs LLC in Evergreen, Colorado, is a mill man at heart. For him, the tried-and-true longevity of milling technology has kept him in the subtractive camp, and there are no signs of him going over to the additive camp anytime soon. “RP is still a new technology, while CNC milling has been around for decades,” he says. “Lots of money has been spent improving milling technology, and that has resulted in cost-efficient and highly reliable equipment.”

As proof, says Karl, one of his two Revos has serial number 45, and he insists that it hasn’t diminished in accuracy.

Producing five or six models a day, five days a week, Karl provides model making and casting services primarily to retail jewelry stores. Eighty percent of his business is stone-set rings, and he’s noticed an increase in requests for logo jewelry over the past few years.

Although the Revo540 mill is de-signed as a compatible machine to Gemvision’s Matrix CAD software, Karl notes that he can process CAD files created in almost any other CAD design program. “Most of the file formats used are standard now,” he reports. “I’ve never received a file that I couldn’t convert in Matrix to run on the mill.”

Karl says preparing most of the files he gets for milling takes only a few minutes, unless the design is more complicated. For example, a piece that includes interior latticework, azures, or undercuts must be broken into separate pieces, which can require additional prep time.

However, once a complicated design is broken down for milling, Karl sees few limitations in the mill’s capabilities. “If the milling machine can’t get to it, the chances of you polishing it are slim,” he says, noting that the Revo can accomplish 95 percent of these complicated cuts.

But while the cuts can be complicated, the operation of the Revo isn’t, reports Karl. “Machining can be very complex, but Gemvision has boiled it down to the push of a button with the Revo. You convert the file, load it into the mill program, and press start. The mill places the model for you and tells you what fixture you need to use. With only a few days of training, novice users can accomplish fairly complex cutting protocol.”

By preprogramming the fixtures with established safety boundaries so there is no chance of tool collision, Gemvision has built safety into the machine. “There are stories in the milling industry about machines programmed incorrectly—they’ll destroy themselves getting to where they are supposed to go,” says Karl. “Since the Revo has preprogrammed boundaries, there is no chance of that happening.”
Since he does his own casting of the models, Karl prefers using traditional wax as opposed to the alternative materials used by some RP systems. “It’s next to impossible to incinerate some of those RP materials,” he says. And carving wax is relatively inexpensive. Karl buys Ferris File-A-Wax in “diving board” size chunks that weigh about 25 lbs. Buying in bulk saves money, and he simply uses a band saw to slice the mammoth pieces into small chunks.            

In addition to the price, Karl likes File-A-Wax because the models can be worked after they come off the mill to make the surface even shinier and smoother. The smoothness of the polished model surface results in a smoother as-cast surface, which means less time spent finishing the model and diminished metal removal. Perhaps most important, says Karl, is Gemvision’s dedication to customer service. “I’ve never had a bad experience with this company when it comes to tech support,” he says. “They’ve always provided outstanding service.”

The quality of Gemvision’s service likewise impressed Jim Curnow of JewelTech in North Bend, Washington, who owns a Revo540. Curnow, a veteran goldsmith of 28 years, began his business as a service bureau, but now runs a retail store that specializes in custom design. “When I learned about Gemvision 12 years ago, I did so through a second party,” Curnow explains. “I bought their Digital Goldsmith software used, but when I contacted them for technical help, they treated me with the same dignity and support as if I had purchased the program directly from them—and today is no different than 12 years ago. I have yet to call this company with a question and hang up the phone dissatisfied.”

But Curnow reports that he hasn’t required an extensive amount of technical support for the Revo, due to the milling machine’s ease of use. “All you do is put the wax on the machine and press a button,” he says. “It’s that easy.” Even an intricate part, such as a detailed four-sided fancy head with prongs, can be executed on the Revo, reports Curnow. “In the past, the only way you could have made a model like this was with an RP system.”

But Curnow, who also owns one of Solidscape’s early RP systems, the PatternMaster, acknowledges the limitations of milling technology. “For pieces with lots of undercuts, RP wins hands down. And in terms of volume, there is no question: High volume users should opt for RP technology. Making 10 models on the Revo is time-consuming because you have to have someone there to pull the wax off and load the next part.” Both Curnow and Karl emphasize the importance of maintenance and cleanliness with the Revo. “The mill is messy compared to an RP system,” says Curnow. “I clean mine daily to keep it in good condition.”

Karl adds that greasing the mill every six months, which takes about 30 minutes, adds to its longevity.