Reaching the apex: Drilling Performance

Like most machine shops, Apex Precision Technologies faces challenges, ranging from higher costs to more demanding customers. “Material costs have been rising dramatically for several years,” said Dan Seacat, co-owner of the Camby, Ind.-based shop. “On top of that, customers want parts cheaper and faster. Most shops think there’s no choice but to pay more, charge less and watch your profit margins shrink. That couldn’t be further from the truth.”

Apex Precision makes most of its custom tools on a81 HMCs. The large, heavy tools are up to 9.25 ” in diameter and can weigh 40-plus lbs. Apex’s combination tools (inset) perform multiple operations, such as drilling, shoulder milling and finishing. All images courtesy of Makino.

Apex is meeting these challenges in part by using machine tools that allow it to implement combination cutting tools and custom fixtures created for customers’ orders. Seacat, who is also Apex’s engineering shop floor manager, said the time savings its custom tools provide and the flexibility of its horizontal machining centers allow his shop to meet just-in-time delivery requirements.

“Most of our orders are for big contracts delivered in kanban quantities to large, demanding customers,” Seacat said. “So we have two contrasting needs: We must produce large quantities, but in small batches. These kanban orders demand flexibility as much as speed. Our response was to develop internal capabilities to design, build and utilize custom-made fixtures and combination tools.” (Kanban is a signal in the JIT system and a directional device that gives information about a material or product, such as quantity or delivery. It is used for controlling production and inventory on the shop floor.)

Apex makes most of its tooling on Makino a81 HMCs. “When you’re using large, heavy tools up to 9.25 ” in diameter weighing 40-plus pounds, you need a strong, accurate and reliable machine,” Seacat said. He said the a81 machines provide the flexibility the shop needs, as well as features such as a chip and coolant evacuation conveyor, rigid spindle design, long axis travels, rapid tool changes and the torque required to handle the shop’s frequent cast iron machining operations.

Large-Part Producer

Apex was founded in 1953 in southwest Indianapolis. The company produces large parts for many well-known, off-road and automotive part suppliers, specializing in differential housings, transfer cases and axles.

Apex President Jerry Jackson began his work at Apex as a lean management consultant. His lean techniques have helped Apex grow from annual sales of $7 million in 2003 to $26.2 million in 2008. The company received ISO 9001certification in 1997 and ISO 14001 certification in 2005. Apex won the Toyota Forklift Supplier of the Year award for 2007, besting 149 other suppliers. Its current 40,500-sq.-ft. facility houses 30 machine tools and other equipment.

“Our lean approach involves more than cutting down on waste,” Jackson said. “True lean facilities also look for reliability, versatility and flexibility in both programming and machining. With limited floor space, we need machines that can demonstrate those qualities.”

Apex first purchased a Makino A55 in 1993, a second A55 the following year and A77 machines shortly thereafter. Several Makino A-series machines were combined in a Makino manufacturing cell to run large-quantity jobs. The cell assigns work and initiates operations automatically, based on machine and material availability, for higher spindle utilization and shorter cycle times with little operator intervention.

The company has since invested in several large new HMCs from Makino, including an A88, three a81s and most recently an a81M. The a81 HMCs are used primarily for quick-run operations and JIT parts. The A88 and A77 machines are used for smaller quantity parts. Some short-run or common-designed parts run on the A77 cell.

Combination Tools

Apex’s engineers and CAD programmers have developed combination tools that reduce tool changes and out-of-cut time, and increase machining efficiency. The tools range from 0.150 ” to 9.25 ” in diameter. They are typically made from carbide or HSS and accept inserts.

To run its combination tools, Apex relies on machines such as the a81s for low-end torque, low spindle runout and the ability to handle long and heavy tools. The combination tools perform a range of operations. For example, one tool drills, shoulder mills and finish bores a feature.

In addition, because they design tools that perform operations in the same area of the part, Apex can often program its machines to go from one operation to another simply by changing the DOC. “It isn’t uncommon for a part to require 50 or more tools,” Seacat explained. “With this many tools, we require rigid machinery with faster tool changes for longer tool life and reduced out-of-cut time.”

Apex’s combination tools typically have several layers, with each separate operation moving farther back onto the tool shank. One 9 ” long tool has a drill on the end, large-diameter boring inserts in the center and even-larger boring inserts farther toward the back. “These tools may look crazy, but they get the job done much more efficiently than changing out a tool each time we need a new operation,” Seacat said. “With greater tool reach, spindle rigidity and tools designed specifically for odd part features, we’ve been able to reduce vibration for higher accuracies and lower scrap rates. This has also enabled us to achieve improvements in tool life, resulting in even fewer tool changes and lower tooling costs.” He noted that changing tools in the a81 machines takes about 2 seconds.

Dan Seacat, engineering shop floor manager for Apex Precision.

Apex’s adaptability is an asset when a customer’s JIT quantities suddenly change. In one instance, Apex had to change from producing 120 pieces one week to 350 the next with only a few days’ warning.

Apex’s ability to engineer combination tools enables it to exceed customer expectations. “A customer used their facilities in Japan as an example of how they thought the part could be most efficiently produced. Their facility produced the part in four operations, and the customer was very surprised when we showed them we could produce the part in only two operations with combination tools,” Seacat said.

Apex can quickly design a combination tool—often in less than 2 days—and produce it in less than a week. The tools are typically applied in operations that would otherwise slow the machining process, such as finishing large holes or reaching through a window fixture to cut a specific feature.

“Not every machine can handle our tooling,” Seacat said. “When your machine places strict limitations on you, it forces you to compromise in your tool and fixture designs.” However, the a81 has features that make using combination tools more effective, he said. For example, the spindle face is just 50mm from the pallet center, which allows the shop to use long tools without losing rigidity.