October 2008 Edition

grinding

Throughput quantum leap

Tool grinding capability changes the name of the game

KEO Cutters found itself at a crossroads. The demands of the market meant increasingly tighter tolerances and specifications for the toolmaker. To stay competitive, the Warren, MI, company would have to put itself on the forefront of innovation.

"We have a very strong brand name and we have been making excellent tools for many years, but to compete successfully with new tool designs and larger diameter tools, we knew we needed state-of-the-art capability," says Chuck Curtiss, president of KEO Cutters. "We needed the capability to participate in a range of spaces, including medical, aerospace, off-road, even jewelry making, auto racing, Ivy League universities, automotive, and more."

KEO found that, like many users of machine tools, it had to expand its capability in order to stay competitive against global players. With improved capability comes an ability to increase throughput.

The company had been known for its center drills which are double-ended tools, but in recent years has expanded its product range to include carbide end mills, keyseat cutters, and dovetail milling cutters, countersinks and miniature HSS steel end mills, and specials. Most of the production is high speed steel.

"We focus on the kinds of tools that most other tool makers avoid, but which are very important to users," says Phil Samuels, marketing vice president. "As a result, we have greater volume in these tools than probably anyone else. That’s been the case from the beginning in 1941."

Meeting the challenge

The investment KEO Cutters made in equipment has given the toolmaker greater capacity and capability to meet the challenging requirements of its most sophisticated customers.

To accomplish that goal, the company invested in three ANCA TX7+ production CNC tool and cutter grinding centers.

"The ANCAs allow us to produce tools we didn’t have the capability to even consider prior to their installation about a year ago," says KEO director of manufacturing Danny
Zuelch.

KEO ordered the advanced tool and cutter grinders with Fanuc workpiece loading robots. The robots works with a pallet system at the back of each machine, loading stock and removing finished tools. Each pallet can hold up to 175 and 756 tools, depending on tool diameter, which permits the ANCAs to operate unattended overnight and through weekends.

Provided with a special wrist motion, the robots can flip tools end for end so the machine can produce KEO’s double-ended tools without missing a beat.

Lights-out capability

Since the ANCAs went to work, throughput has improved significantly. For some tools, the turnaround from bar to shipping box has gone from 30 days to two days. Much of this has come as a result of the ANCA capabilities, including the ability to changeover quickly and to handle special customer requirements.

"The cycle time for some of our tools is not always shorter, but our overall ability to deliver accurate tools quickly has improved a great deal," says Zuelch. "The lights-out capability was huge for us and saved a lot of labor, plus the consistency of production has been improved — the first part is always the same as the last.

"And we have the capability to hold tolerances on specials just as accurately as we do on our standard tools," he says. "At the end of a day running specials, we can use the ANCA to run standard products all night long. We just load the pallets, select a new program, and hit ‘start’."

The ANCAs also are helping the toolmaker get better at what had already been one of its specials: make any design or size of any center drill, standard or special.

"Some center drills have angles, flats, and flutes all in a specific relationship to each other," says Curtiss. "To try to make a slightly different design in the conventional way would take a great deal of time and be in queue with all our other work or we would have to interrupt production to do the special. With the ANCAs, we simply change angles, points, and specifications in the program and have the tool done accurately tomorrow."

Since the ANCAs went to work, throughput has improved significantly at KEO. For some tools, the turnaround from bar to shipping box has gone from 30 days to two days.

This type of tool-making capability has allowed KEO to successfully pursue more specialties.

"A lot of customers specify flute orientations, which means we have to grind flats in relationship to the flutes within a couple of degrees to the cutting edge," says Zuelch. "Previously, this would be done with human intervention of the most skilled workers in the plant. With the ANCAs we can do it faster and consistently first to last. Lights out."

Streamlined process

The machining capability of the powerful ANCAs also means that the company can streamline its tool manufacturing process.

"With the ANCAs we also been able to eliminate a lot of milling operations," says Zuelch. "Where tools used to be milled with a milling cutter, we now can grind from a solid bar, which results in a higher quality, more consistent surface finish.

"Standard drill making equipment has fixturing," continues Zuelch. "And that takes some time to changeover, adjust, and tryout to do another tool. On the ANCA, it takes me two seconds to tick in the part program the angle I want to change, for example, and how, and then I can drop the part complete. For that reason, we can have a much faster turnaround with the ANCAs, rather than running a tool through a series of operations through the plant. Workpiece handling can add quite a bit of in-process time."

The design of the ANCA TX7+ allows for precision tool production. The machines feature a 49hp, 10,000rpm spindle, an automatic wheel changer, optional auto-loading system, and a 3000rpm headstock.

Built for rapid changeover

The TX7+ can be programmed to automatically perform a complete changeover of wheel pack, coolant system, workholding collet, and pallet in less than three minutes, allowing KEO to manage batch sizes and handle specials seamlessly. Typical machines require 15 to 20 minutes, to even several hours, for changeover to produce another type of tool. For the TX7+, wheel packs and corresponding coolant manifolds are prepared off-machine and quickly exchanged to grind a new tool.

The direct drive, high-speed (3000rpm compared to 200rpm typically) work head (A-axis), allows the company to include cylindrical grinding operations, preparing stock for its tool grinding process, and to fully grind stepped or tapered blanks. OD grinding for reamers and drills is also possible.

These capabilities mean tools can be produced complete in a single setup, and this helps to minimize production time for many tools that may have required two or more operations to complete.

The capability of the machines has actually allowed KEO to develop a system for delivering tools quickly — called KEO KWIK.

In addition to speed of changeover, the CNC wheel changer allows the manufacturer to utilize up to eight wheels in a single setup, accomplishing more operations per setup and allowing complex and special tools to be dropped complete. Mounted on a manifold, coolant piping changes with the wheel packs, so that coolant flow is always tuned to the wheel in use for optimum coolant application.

The TX7+ also includes in-process dressing which avoids some downtime and helps assure optimum wheel condition, resulting in consistent grinding and tool quality. Mounted to the back of the chuck on the high-speed work head, the dresser roll is easily accessed or introduced to the wheels with minimal axis strokes.

Now on the right side of the technological curve, KEO Cutters is well on its way to meeting the demands of its customers for precision tools.

ANCA

What do you think?
Will the information in this article increase efficiency or save time, money, or effort? Let us know by e-mail from our website at www.ToolingandProduction.com or e-mail the editor at dseeds@nelsonpub.com.