Mold manufacturer turns to high-speed machining for business growth
C.M. Solé, S.A.
NX Machining for high-speed machining (HSM) lets C.M. Solé take on more work
Planning for growth
C.M. Solé couldn’t take advantage of the late-1990s boom until it boosted the efficiency of its mold manufacturing process. C.M. Solé, a manufacturer of high-precision plastic injection molds, guarantees its products for one full year or one million injection cycles. With quality assurance like that, it’s no wonder that during the late 1990s the company found itself with opportunities to grow. Orders were coming in at an increasing rate from customers such as Hewlett-Packard, Lear Corp., Alcoa CSI and Schneider Electric. But company managers Jaume Solé (Technical Manager) and Josep Solé (General Manager), sons of founder D. José Solé Pagés, knew they were approaching the limit of what the company could handle. “We needed to reduce lead times dramatically or we would not be able to cope with the excellent growth opportunities of the bullish market,” explains Josep Solé.
The Solé brothers identified electrical discharge machining (EDM), and in particular electrode manufacturing, as the critical process where a significant time reduction could be achieved. Those days, a typical mold required the construction of between 400 and 500 electrodes. The Solés set a goal of cutting this number in half by adopting high-speed machining (HSM) techniques. HSM would make it possible to do some of the carving of the mold cavity formerly done by EDM directly on steel using special high-speed milling machines. (Some amount of EDM would still be required for places in the cavity that are not easily milled.) HSM eliminates much of the electrode manufacturing while providing excellent surface finishing that eliminates the grinding needed after EDM.
Setting up a high-speed system
C.M. Solé had no trouble locating high-speed milling machines. Finding computer-aided manufacturing (CAM) software was another matter. “Only a few programs are capable of feeding the machines with the detailed information for milling at very high rates,” says Jaume Solé. The company conducted a series of pilot tests using real parts to evaluate CAM programs they thought would be suitable for HSM.
C.M. Solé selected NX™ Machining software for a number of reasons. In addition to its strong support for HSM, the software is open by design, able to accept customers’ solid models in a variety of data formats. C.M. Solé also appreciated the enormous flexibility of the software’s machining strategies and process definition, as well as the ability to control finish tolerances. Finally, the proven quality of the technical team at Siemens and the implied guarantee of support were also paramount in the final selection.
C.M. Solé paired NX Machining with a Mikron HSM700 high-speed milling machine. The conversion to this system enabled the company to meet its objective of decreasing the electrodes needed in the production of a typical mold. The company actually surpassed the 50 percent target, now requiring somewhat less than half the number of electrodes it needed in the past. As a result, the company is spending less time on electrode manufacturing. It is also spending correspondingly less time on finish grinding.
These efficiencies have helped C.M. Solé decrease overall mold manufacturing time. Since the introduction of NX Machining and HSM, total mold manufacturing time has dropped by 20 percent to 30 percent. While much of this is due to the need for fewer electrodes, NX Machining’s ability to simulate toolpaths also saves time by allowing the company to spot and fix errors prior to cutting metal.
Most importantly, overall lead time has decreased as a result of the new system, allowing the company to take on an increased volume of work and meet customers’ expectations for fast delivery. At the same time, the company’s excellent quality has been maintained due to HSM’s high accuracy and excellent surface finishing. The Solés estimate that the costs of the new equipment and software have been more than justified by these results. Concludes Josep Solé, “Results show us that our decision to introduce HSM was right, and we are now collecting the fruits of our investment: excellent accuracy and surface finishing with reduced manufacturing time.”