VMC Design Turned Upside Down - YCI Supermax breaks from convention with new machine tool design - Brief Article

Is there room for improvement in the fundamental design of a vertical machining center? At least one machine tool builder thinks the answer is yes. For its larger-travel VMCs, YCI Supermax (Santa Fe Springs, California) has broken from design convention to place the Y axis on top of the X axis. Improved precision is the reason for the change.

A conventional VMC has X atop Y. This means that support for the work remains near the middle of the machine no matter where the work is located in X. As the work moves toward extreme positions in X, overhang increases. Some machine tool builders address this problem with non-integral supports located on either side of the base. By contrast, placing the X axis on the bottom of the machine results in a one-piece base providing consistent support along the machine's travel.

There are tradeoffs. According to company executive vice president Bryan Chen, the design's one-piece, T-shaped base results in a machine that is more expensive both to manufacture and to ship. However, for large, heavy jobs, the improved precision may justify the added cost. The one-piece design not only counters overhang, it also improves leveling accuracy.

It may also improve floorspace requirements. The footprint for one of these machines is 20 to 30 percent smaller than the footprint for comparable machines with the same travels, YCI says. This design is available for machines featuring X-axis travels of 59 or 82 inches.