Plastic injection molds that form products ranging from an everyday flip-top lid for a grated cheese jar to the sleek, elegant compacts and containers for cosmetics are built at AJ Tool. Located in Hubertus, the company has 26 employees and operates two shifts. For more than 14 years owner Al Jubeck's choice in sinker EDMs has been Mitsubishi from Schweda.

"I was impressed with the quality and repeatability of these machines, and the service from Schweda and Mitsubishi," he said.

AJ Tool was one of the first Wisconsin users of the Mitsubishi Fuzzy Logic control, so it seemed natural to start the new millennium with a new Mitsubishi EDM equipped with the new Fuzzy Pro-2 control. Installed on January 2, the new machine, which also features E.S.P.E.R. programming, has been setting records for speed and finish. For example, the mold for the flip top lid has four cavities. In eight hours, the old EDM burned one cavity and was halfway through the second, according to Matt Stiever, a toolmaker who, along with John Gonzales, operates the EDM department at AJ Tool.

Fuzzy Pro-2 enables the new machine to burn all four cavities in six hours, Matt said, noting that the faster burn time results in less electrode wear. The flip-top lid has a ridge around the top that facilitates stacking the lids during trans-port. Matt pointed out this ridge as a former problem-area of electrode wear which the new machine has eliminated." Longer electrode life can easily save $1,000 to $3,000 on a mold," he added.

Fuzzy Pro-2 burns with induction rather than resistance, eliminating build-up of an orange-peel-like surface on the electrode. Finish is particularly important to AJ Tool in the molds it makes for the cosmetics packaging industry. Matt said that for a cosmetic case the new EDM could burn eight cavities with one rougher and one finisher and produce a finer finish than the old machine would have produced using more electrodes.

Introduction of the E.S.P.E.R. programming system into the shop has been a test of faith in the machine's ability to suggest and apply the best programming strategy. Matt has 15 years experience, John has 10 years experience, and they both know just how to program their Mitsubishis to get the results desired. However the E.S.P.E.R. system, with artificial intelligence, sometimes takes a different path to achieve the same end. For a less-experienced operator this is a great advantage, because the system prompts the operator to enter all the necessary information. For the experienced EDM operator, when E.S.P.E.R. programming makes its own choices, sometimes it is tough not to second-guess the system. Matt said that he has been well pleased with the machine's results, however, and he prefers E.S.P.E.R. to the original F.A.P. system because he can view a 16-cavity job all on one screen, instead of having to go through 12 screens. E.S.P.E.R. is ideal for large jobs with lots of small burns, Matt noted.

To keep pace with the needs of tool and die shops, Mitsubishi EDMs continue to evolve, adding ever-improving technology for better and easier operation. In Mitsubishi's world of change, quality endures, and to AJ Tool, that has made all the difference.