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100 MMS June 2014 mmsonline.com feature the more he wanted to be able to machine them. Lithophanes are etched or molded artwork tra- ditionally made from thin, translucent porcelain. They have what looks to be a rough image that comes alive with backlighting (see the photos on page 99). He sought to machine these for friends and family from Corian plastic, and began looking for a CNC machine tool that would enable him to do that. Clearly, machine size was a consideration, because it would reside in one bay of Mr. Rosen- thal's two-car garage (the other bay is reserved for his wife's car). The CNC machine he purchased is an industrial benchtop unit from S&W; Engineer- ing that certainly is no toy. Mounted on a steel frame, it weighs 850 pounds and fe ature s a heav y-dut y steel structure with a proprietar y internal casting to minimize harmonic resonance and add structural integrity. Its X-, Y- and Z-axis travels measure 18 by 12 by 8 inches, and it was purchased with a number of options that brought its total cost close to $100,000. This includes a 60,000-rpm spindle to provide the speed neces- sary for small-diameter tools in balanced toolhold- ers to perform detailed cuts in plastics and alu- minum. He also ordered the machine with a 10 -position automatic toolchanger, a touch- trigger probe, a tool-length measurement probe and an optional rotary table to enable four-axis machining (although he's yet to use the rotar y table). In addition, the machine has an air blast system, which is helpful for machining plastics, and an oil mist delivery system for aluminum parts. Mr. Rosenthal first used the machine to create a number of lithophanes and other relatively simple personal machining projects. In 2013, however, he added his first and, at least for now, only customer: a venture capitalist acquaintance who learned about the machining work he was doing. His customer understood that he wasn't a hugely skillful machinist at that time but decided to fe e d h i m s o m e s i m p l e p rotot y p e wo r k i n plastic materials knowing he'd likely offer quicker t u r n a r o u n d t h a n c o n v e n t i o n a l s h o p s t h a t often don't like to take on one-off-type work. Plus, the customer preferred machined prototypes over those printed via additive manufacturing because machined surfaces are smoother than the slightly stair-stepped finish additive equipment leaves behind. Mr. Rose nthal s ays the CA M sof t wa re he originally used was functional but still required him to make a number of choices related to cut- ting data. These choices would have likely been easy for a veteran machinist to make, but not for him given his limited experience. Af ter some i nve s ti g ati n g, M r. R o s e n th a l l e a r n e d a b o u t iMachining CAM software from SolidCAM and purchased the company's 2D iMachining module. He says what was important at that time was not necessarily minimizing programming or machin- ing time, but rather generating tool paths that wouldn't break the small-diameter tools he was using. What he particularly appreciated about the software was how he could leverage its built-in intelligence to generate effective tool paths based One signature feature in iMachining software is its "morphing spiral" tool path, which maintains a consistent load on the tool through consistent tool engagement. Another is its Technology Wizard, which uses application-specific information to determine the optimal cutting data for a job. 0614_MMS_retired.indd 100 5/14/2014 8:43:56 AM