Maximizing Efficiency

Doesn't Have To Be Like Pulling Teeth
Makino Helps Enhance A-dec Productivity

Most people prefer to think of a trip to the dentist as little as possible. While it’s still not going to make many lists of favorite ways to spend an afternoon, visiting the dentist has become a much less unpleasant experience over the relatively recent past. In large part, this can be attributed to the efforts of companies like A-dec, a manufacturer who has spent the past 40 years devising solutions to maximize the comfort of dentists and their patients.

Founded in 1964 by Ken and Joan Austin, A-dec began by offering a single product. A true innovation at the time, the AVS (Air Vacuum System) performs high-speed evacuation of water and debris from a patient’s mouth. The original design proved so reliable that A-dec still sells 400 of the units on an annual basis.

The success of the AVS propelled A-dec’s growth, allowing for further innovations. Today, the company maintains its position as the largest dental supplier in North America by focusing primarily on ergonomic issues. With its latest product, the A-dec 500 dental chair system, the company reexamined every aspect of chair design to maximize patient comfort and eliminate factors that often lead to spinal and vascular problems in dentists.

In order to gain the competitive edge provided by new technology and the lean manufacturing attributes of cellular manufacturing, A-dec sought out Makino to provide the machinery necessary to manufacture the components for this new product.

Rapid Response [back to top]
A-dec already had two Makino A55E horizontals with a 24-pallet Makino Machining Complex (MMC) to compose one of its primary manufacturing cells. They then decided to add two Makino a81 horizontal machining centers (HMCs) with a 12-pallet MMC to compose a new cell for the new 500-model dental chair.

Due to tremendous internal pressures to go to market quickly, the components for this new chair had to be manufactured fast and accurately. A-dec needed rapid acquisition, setup, training and lean operational output on the a81 cell. They worked with Makino and Ellis Machinery, its distributor in the northwestern U.S., to get the system installed and operating as soon as possible.

"The new product required all new parts, all new fixtures and all new programs on the two a81 horizontals and the MMC," according to Tony Getsinger, machining manager at A-dec.

Lean Operations [back to top]
Rapid response and setup was necessary in the development and creation of the new A-dec 500-model dental chair. But the company now had to face a plethora of manufacturing challenges that required a Makino lean manufacturing solution.

Getsinger says that A-dec was able to institute several lean manufacturing concepts once the Makino machining cell was in place. "We eliminated set-up time on repetitive jobs, which saved us a significant amount of process time. We were also able to eliminate all dead spindle time when setting up a new part, and to run the operation unattended.

The new product required all new parts, all new fixtures and all new programs on the two a81 horizontals with an MMC.

"This combination allowed us to make parts in real time to meet customer orders. The powerful and user-friendly Makino cell control software, coupled with the reliability of the Makino machines, allows A-dec to achieve true JIT (just-in-time) manufacturing."

"When we had any type of operating issue with the Makino a81 and MMC cell, Makino got right on line and corrected the issue," says Getsinger. "We have called the company after hours, when all other machine tool operation experts have gone home, and we are able to talk to a qualified technician who was able to help us."

Manufacturing Solutions [back to top]
One of the first challenges that arose was in the formation of the newly designed base plate of the chair. The engineers at A-dec focused on giving the base plate a smaller footprint. This provides dentists the ability to work closer to their patients without having to bend at the waist which can lead to fatigue and, over an extended period of time, spinal problems.

"The new base plate was really a radical shift," says Brian Cappoen, A-dec senior programmer. "The old base was an aluminum part weighing 37 pounds. To get the stability we needed with the smaller footprint, we did a complete re-design and changed to a cast iron part weighing 120 pounds. The new part design created new challenges with tool reach and process stability and reliability."

While examining the best process to machine the job, A-dec worked with Makino and Sandvik Coromant to come in and offer a fresh perspective. Makino supplied the machining solutions, and Sandvik suggested use of the Coromant Capto modular toolholding system to dramatically increase the reach of tooling without sacrificing any of the speed, quality or accuracy.

The new part design created new challenges with tool reach and process stability and reliability.

"By stretching out the Capto and then putting a hydrogrip chuck at the end on the Makino machinery, we were able to get to where we needed to be on tool length," explains Cappoen.

"With the Coromant Capto coupling, we have drills that are hanging out 18 inches and that are holding tolerances of 0.001 inches on the Makino machines. Also, it is small enough that we’re able to get through narrow passages in the fixtures to reach where we need to be.

"The MMC cell controller on the Makino system allowed for greater machining flexibility to maximize spindle in-cut time," says Cappoen. "Using the Makino cell control technology software creates even more opportunity for unattended operation. Utilizing other Makino machining technology allows us to check for tool breakage. The tool is checked outside of the Makino machining envelope as it is being put away so it does not effect the part cycle times."

Productivity Improvement [back to top]
A-dec developed a lean manufacturing team to gather thorough data on parts that were contributing to bottlenecks. Several weeks later, members of the team returned with their findings and recommendations on over a dozen parts.

With the technology provided by Makino and Sandvik, one troublesome part that had a total cycle time of 40 minutes was initially reduced to 28 minutes. Changing the end mills allowed for an increase in machine operation feedrates from 30 ipm to 60 ipm, which cut the part’s total cycle time to just over 11 minutes. The CoroMill® Plura end mill that was utilized permitted the increases in speeds and feeds, reflecting a total time savings in the process of over 60 percent.

After nine months of integrating the team’s recommendations with the machine performance of Makino and the tooling of Sandvik, A-dec estimates that they have eliminated over 4,000 machining hours from its processes annually. Weekly production runs have grown by 50 percent without the addition or replacement of any machines.

On another challenging part, A-dec was running at 4,000 rpm and 40 ipm to achieve the minimum surface finish the part required, which was 32 µm. By changing to the new CoroMill 590 face mill with diamond inserts from Sandvik, and increasing the Makino machine spindle speed up to 14,000 rpm and the feedrate to 1,000 ipm, the finish was actually enhanced to 20 micron. The process then ran in just 20 seconds instead of the previous 2 minutes and 40 seconds.

Such improvements in machining processes have allowed A-dec to maximize efficiency and minimize costs, while experiencing steady growth. In 2004, sales grew by 24 percent and continued growth is expected.

A-dec credits its machining personnel and the technology of Makino and Sandvik Coromant with helping to enhance productivity—with much less pain than a trip to the dentist!

Story reprinted and updated courtesy of
A-dec and Sandvik Coromat.
A-dec USA, Newberg, Oregon
Phone: 1-800-547-1883
E-Mail: domestic@a-dec.com
Web: www.a-dec.com