Software increases spindle utilization: Drilling Performance

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END USER: Mainland Machine, (805) 543-7149, www.mainlandmachine.com. CHALLENGE: Increase spindle run times. SOLUTION: CAM system that enables efficient programming when machining with custom fixture plates. SOLUTION PROVIDER: DP Technology Corp., (805) 388-6000, www.dptechnology.com

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Competing in today’s stormy economic climate requires maximizing spindle run times because value isn’t being added to a workpiece if chips aren’t raining down. Mark Ames, owner of Mainland Machine, sought to dramatically increase the San Luis Obispo, Calif.-located job shop’s spindle run times and accomplished it with a CAM program capable of maximizing the benefits of several machining strategies being implemented at the shop.

Founded in 1983 by Ames, Mainland has machined parts for photography gear, microwave communications, the medical and aerospace industries, motorcycles and motion control equipment. In addition to machining, the shop offers assembly, laser engraving and product design services. “At Mainland, we do not just make parts to a print, we get an understanding of what the part is doing,” Ames said. “Just because a part is made to print does not mean it is going to perform the function the customer needs it to; parts aren’t always ‘toleranced’ correctly.”

Mainland was able to support its customers’ needs with tried-and-true methods such as machining several parts one side at a time in multiple vises on its 17 Fadal 3-axis vertical machining centers. However, this method limits spindle run time to about 33 percent efficiency because tools are in the cut for a relatively short period of time—from seconds to a few minutes. This requires the spindle to stop frequently for tool changes, which consume about 20 seconds on a Fadal VMC.

ESPRIT software performs a simulation of Mainland Machine’s pallet system with two setups. Image courtesy DP Technology.

That time means little when the tool is in the cut for an hour but is significant when, say, applying 25 tools to cut a group of parts with a 15-minute cycle time, Ames noted.

To increase spindle run time, Ames upgraded some of its VMCs with Midaco pallet changers, which enable a machine to run one pallet while an operator unloads and loads the next one. To maximize the potential of the pallet changers, Mainland also designs and builds fixture plates that hold workpieces and allow multiple machining operations on multiple parts. For example, a part that requires two operations could be machined in a fixture holding four rows of 10. The first two rows could be operation No. 1 while the next two could be operation No. 2. Therefore, each time the operator changes out, 20 parts will be completed.

However, Mainland discovered that its CAM software was only capable of generating code that would machine multiple parts of the same operation or generating code that would machine all of the first operation, then the entire second operation and so on. The latter requires many redundant tool changes. “Most CAM software programs are designed to program one operation at a time,” Ames said. “They’re not set up for programming a part complete all at one time.”

Mainland Machine uses a Midaco pallet system with a custom fixture plate, designed and built in-house, and ESPRIT software to streamline manufacturing. Image courtesy DP Technology.