Production Machining - Your access to the precision machining industrial buyer.
Issue link: https://pm.epubxp.com/i/105154
MEDICAL MACHINING :: The finished part extends from the bushing, waiting for engagement of the subspindle's collet for backworking operations. until scrutinized, revealing subtle contours and details that could be trickier to manufacture. Oddly, a few parts stuck out that were obviously not Swiss. Actually all of the parts Mr. Ortiz was showing us really were made on Swiss machines, and some of them, for complex medical devices, were simply not what one would consider coming from a Swiss machine. Many looked more like they should come from a machining center. However, as Mr. Ortiz explained, the multitasking capabilities of today's CNC Swiss machine technology blur the lines between some machine tool operations. "If a part fts on a Swiss-type, why not run it there?" says John Makris Sr., president of Roberts Swiss. "With all the innovation over the past 20 years, there's little a Swisstype can't do, and they have several distinctive advantages. First and most important, we don't need to handle parts for secondary operations." Mr. Makris continues, "Secondary operations are costly. Te fastest and most advanced automatic part handling systems are custom designed and cost big money to buy and maintain. It's even worse if the parts require handling by humans. Why handle parts more than once if we can do them right the frst time in one setup?" 30 PRODUCTION MACHINING :: FEBRUARY 2013 Te lack of custom fxturing is another huge beneft of Swiss-type. Fixturing amounts to a collet and a guide bushing. Collets and guide bushings are a relatively low-cost fxturing method, such as a universal workholder, within operating their range. Again, the rigidity this simple system afords the process is impressive. Te bushing concept is at the heart of another great advantage—the inherent accuracy of Swiss-types. Te unique guide bushing design means that everything is concentric because of the support and synchronization of a collet and guide bushing. Swiss-type concentricity is typically ±0.0001 inch. In many cases today, these machines actually use two collets. Te second is for the subspindle. Tat collet might be a standard size or might be a custom shape for the fnished front-end of the part. Tis ability to hold the part by the front end after it's done means the machining process can continue machining on the back side, with positive alignment with the front-end, and with no handling. With live tooling that can drill or mill on the front or back end of the part from any angle in space, access to virtually all possible surfaces is provided.