Every once in a while, Jack McGrail will cut a potential customer's part for free, just to prove a point. These rare occasions usually involve customers who are convinced that the work is best suited for Mr. McGrail's wire EDM equipment. Typically, their initial skepticism becomes pleasant surprise with the revelation that he can meet required specifications in less time using abrasive waterjet machines from Omax (Kent, Washington).
Mr. McGrail is president of Jack's Machine Co., an 11-person job shop in Hanson, Massachusetts that specializes in both waterjet and EDM. The shop got its start in 1985 offering high-volume wire EDM work. The company added its first abrasive waterjet cutting system 10 years later, a move motivated by processing speed. An abrasive waterjet can cut parts that don't require extremely tight tolerances much faster than wire EDM, Mr. McGrail says.
As accuracies continued to improve, the shop invested in newer machines that enabled moving even more parts from EDM to waterjet. Its current equipment consists of two JetMachining centers from Omax: the 2652 and the 55100. The cantilever-style 2652, which is the shop's newest waterjet, features Omax's Maxjet 5i nozzle, programmable Z-axis movement and a sealed ballscrew drive system. It offers X- and Y-axis cutting travel of 52 by 26 inches and a table size of 69 by 30 inches. The 55100 is a larger cantilever-style machine, sporting a table size of 126 by 65 inches and X- and Y-axis cutting travel of 100 by 55 inches. The cantilever Y axis mounts on a bridge X axis, and the machine features a motorized Z axis. One advantage of this design is that it provides three open sides for material loading, Mr. McGrail notes.