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Asking for the moon: faster and cheaper machining and tooling are what OEMs want.

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Just like every other segment of an orthopedic OEM's supply chain, machining and tooling vendors are being pushed hard by their customers to deliver more services at lower cost. is an increasingly tough challenge for machinists and tooling shops, especially as products become more complex, smaller in size and incorporate new materials. To stay competitive, vendors must continue to invest in sophisticated equipment and better control systems to assure high quality, repeatable results. This especially is true for U.S. Food and Drug Administration (FDA) approvals and proper validation of process procedures. It is for these reasons, especially, that many machining and tooling suppliers are experiencing more demand for automation and intelligent equipment that simplify processes, increase quality and reduce human error.

This tremendous pressure from OEMs to reduce costs has changed the way contract manufacturers conduct business. Not too many years ago, components that required extreme levels of machining talent and expertise could demand the premiums required for a shop to maintain the high level of talented people needed to manufacture such components. Those days are gone-with the cost-reduction pressures in today's environment, OEMs are asking suppliers to do more for less.

This means machining and tooling vendors must be leaner and more productive than ever before.

"These requirements, whether coming from regulatory, design assistance, consultation, delivery speed or tolerance, are all increasing--but all the while these increased requirements are being demanded for less cost," said John MacDonald, vice president for AIP Precision Machining, a Daytona, Fla.-based provider of custom-machined, high-performance plastic components.

Not only do OEMs want lower costs, they want services delivered more rapidly.

Design-to-dock delivery times keep getting tighter. Therefore, machining and tooling companies are seeking ways to add value, streamline operations and reduce cost. The best way to do this is getting machining and tooling vendors involved earlier in the design process to share their expertise and enhance manufacturability. This includes packaging engineers, who often are the last team members "invited to the party," and very often receive little finalized product data to work with to initiate package design. This timeline compression cascades to the thermoform tray supplier, as well as the package sealer supplier and their respective tooling deliveries.

"When product managers or device engineers do not consult with the packaging engineer during the design phase, there may be some surprises later on that delay things," said John A. Abraham, president of Cincinnati, Ohio-based AtlasVac Machine LLC, which manufactures medical device tray sealers and sealing tool nests. "For example, they might discover there is no capacity in the packaging cell they planned to use, or that the size of the tray and tool will not fit the sealer. Or they might learn the package will require inner tray or inner alignment pieces to safely package the product, which takes more design time and testing. All of these scenarios involve more spending and impact the timeline."

Invest in the Right Equipment

Being able to manufacture a customer's smaller, more complex product in a shorter timeline (as well as nailing down future work) means investing in the technology that will achieve the accuracy, repeatability, tight tolerance and speed the OEM expects. An increasing number of orthopedic projects call for high-speed machines with large banks of live tools that can produce complex and sculpted shapes. For example, Okay Industries Inc., a contract manufacturer of precision machined and stamped components and assemblies based in New Britain, Conn., recently purchased a Tsugami CNC [computer numerical control] Swiss nine-axis machine with a programmable B axis to address these needs. The equipment can machine virtually any angle and produce contoured and sculpted parts in one operation with simultaneous five-axis machining up to 20 millimeters in diameter-making it ideal for machining temporary and final abutments, threaded and conical implants, pump impellers and rotors, biopsy cup jaws and angular dental implants.

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"The B-axis Swiss CNC can be easily and quickly set up to make parts with intricate features that are usually part of a secondary operation," said Sean Stowik, business development executive at Okay Industries. "This allows customers to test designs and design changes quickly for less. Production parts processed with multiple operations can be transferred seamlessly to one operation providing dramatic cost savings and improved quality."

For example, Okay Industries was able to take a customer's four-piece, laser-welded sub-assembly design and instead engineer a complete, single-part replacement in one operation, reducing lead time by weeks and cost by nearly a third.

Starrag USA, a Hebron, Ky.-based provider of multi-axis machining equipment, indicated it is receiving more requests from medical device and orthopedic implant manufacturers for equipment that can produce complicated parts that require turning, drilling, milling and even grinding, all in one setup. One of the machines the company provides--the Bumotec S-191, can handle this kind of work and maintain tolerances of +/- 3 microns throughout the day.

"Doing it all in one setup saves time and eliminates any variance in accuracy and quality," noted Stephan Swanson, sales manager for Starrag USA. "Anytime the part is handled, especially transferring it from one operation to the next, the operator runs the risk of creating variation, or even damaging the part in the process."

The Bumotec S-191 is a three-, four- or five-axis machining center with swivel B-axis spindle option and rotary table. It can be stopped at any time to inspect the parts without losing any positional accuracy during the inspection period.

"This is very important for our customers," said Swanson. "As parts get more complicated, the inspection process becomes much longer and the possibility for thermal drift increases."

Swiss machines especially are useful for producing small parts with very tight tolerances. For example, one application for Swiss machining that is on the rise is the precision machining of needle tips.

"Swiss machines can be used to produce intricate tips at tighter tolerances, basically eliminating formerly used grinding processes," indicated Tom Plantenberg, director of sales and marketing for Marshall Manufacturing Company, a Minneapolis, Minn.-based provider of full-service precision machining and assembly. "Swiss abilities can also be combined with laser-cutting and specialized bending techniques to manufacturing medical-related products that have multiple components that need to be joined together."

Early One on One

Machining or tooling solutions typically vary from customer to customer and project to project. Finding the best solution involves getting the machining and tooling vendor involved as early as possible in the design process--this is where creativity and innovation are at the forefront. Discussions include engineering data, design specifications, end-use environment, materials, assembly options and manufacturability expectations. The goal for the machining and tooling specialists is two-fold: 1.) completely understand the customer's performance expectations for the component, and 2.) tap their own deep experience and expertise to help the customer design the best possible manufacturing solution for the component. Repeated successful outcomes and growing trust will deepen the partnership with time.

"As with many innovations, they tend to come to us along the manufacturing path," said MacDonald. "This typically occurs in the form of process development and improvement during the actual programming, fixturing and setup operations. Each material reacts differently to being cut, held and modified. Even a slight change in geometry can result in a different material behavior from what we might have otherwise expected, based on prior experience."

For example, simply changing the way a part is fixtured can result in an entirely different feature size or condition. This is due to existing and machined-in stresses, as well as the low modulus of polymers. The engineering team might enter a project with a well-conceived manufacturing plan only to find that, due to a feature wall thickness, tooling or feed rate, an entirely different outcome is encountered.

"This is where the real process development occurs, "MacDonald added. "Our engineers apply over 30 years of polymer machining knowledge to work through the challenges of delivering some extremely challenging geometries and tolerances in relatively soft materials."

Recently, AIP had machined some thin-walled carbon fiber-filled PEEK rings for an aerospace application. Even after numerous stress-relaxation cycles, they identified variability of part features off the machine, from one end of the slug to the other.

"Once that issue was brought under control, the customer modified the part wall thickness slightly--less than 250 microns-and we started to note different behavior throughout the slug," said MacDonald. "We continued process development until we achieved repeatable tolerances."

In another example, a customer recently called on Marshall Manufacturing Company to produce a new product it had designed. The product consisted of seven precision machined components, all requiring very close turning and boring dimensions, followed by labor-intensive assembly. The product appeared to work for the application for which it was designed, although the customer was experiencing some assembly failures.

After conducting a "design for optimum manufacturability" study, Marshall's engineering team suggested an alternate process that virtually eliminated the need for multiple machined components, instead making the part from a single piece of material. This new process employed bending and forming stainless steel wire to new design specifications, while maintaining tolerances of pre-machined features.

"This saved our customer considerable lead time and reduced the final part cost 62 percent over that of the original design," explained Plantenberg.

Making It Faster

Every minute counts when it comes to meeting timetables and product launches--but as products become more complex with higher tolerances, it is harder to meet those timelines because these products, by nature of their design and materials, take more time to produce. That's why machinists and toolers are always looking for innovative ways to enhance speed and efficiency.

More companies are realizing that finishing a part in one setup saves a lot of time and money, making it worthwhile to investment in the equipment that can make it happen (for example, a Swiss machine can cost $300,000 or more). Doing everything in one step eliminates costly secondary operations. Investing in staff training also helps maximize quick setups and fast changeovers.

Machine features include multiple retaking options, quick-change material-handling colets, and intuitive customer CNC interfaces. Machine controllers are more operator-friendly with conversational programming and better simultaneous control of multiple axes and tooling for increased accuracy and overlapping of operations.

"Additionally," said Damian Zyjeski, CNC production development manager for Okay Industries, "user-friendly innovations for controllers on high-tech, state-of-the-art machines allow the CNC technician to complete more tasks in a shorter period of time. This also reduces the learning curve for this equipment. These machines are ready to produce in rapid time--a plus for both the customer and supplier."

Speed of process also can be affected by tooling nests--for example, where multiple trays are being sealed on a single cycle. All efficiencies are lost (as well as quality of package reduced) if the operator cannot quickly remove the numerous packages from the tooling, or accidently damages the seal edge. As a result, an increasing number of packaging engineers are recognizing the value in single-piece precision CNC machined tooling nests.

For Atlas Vac Machine, this means typically starting with a Mic6 aluminum tooling plate and machining tool profiles into the single plate. This results in superior tools that cannot go out of alignment and also eliminates the stack-up of dimensional tolerances from multiple pieces used in older design tooling.

"Self-ejecting tooling can provide the speed and ease of removal," said Abraham. "One customer requested this on an eight-cavity tool installed on sealers running three shifts per day. There would be no way to hit the aggressive cycle times without the self-ejecting assist to the operators."

Technologies Advance

3-D printing and precision electrochemical machining are starting to show great promise for economically manufacturing complex shapes with high quality. Vendors are working closely with OEMs and contract manufactures to develop customized machining solutions, especially for new materials such as polyetheretherkcrone (PEEK), carbon fiber, sintered ceramics and even quartz. For example, the Bumotec S-191 provides grinding operations with its 150,000-revolution-per-minute spindle attachment. Special guarding also ensures the grinding swarf (material such as metallic particles and abrasive fragments removed by a cutting or grinding tool) is contained to insure longevity of the machine tool.

AIP Precision Machining constantly is developing new techniques and researching custom tooling and fixturing methods for critical custom machining of plastic and composite components. Due to the competitive landscape within the machining industry and non-disclosure agreements, MacDonald cannot share the details of the proprietary machining techniques and tooling solutions the company has developed.

"We are continuing to look at methods to reduce material cost via increase yields for expensive implantable PEEK and surgical-grade, carbon-fiber polyetherketoneketone (PEKK)/PEEK variants," said MacDonald. "This involves getting much more creative with the materials, machining processes and tooling in order to squeeze out every last ounce of yield we can for a given part. This will allow us to offer the customer cost improvements, while still being able to maintain and challenge our workforce."

For Starrag USA, the majority of its machines are "turn-keyed" for specific customer operations. This includes special improvements related to the specific application, along with programming of the part, sourcing tooling, developing the process, part run-off and customer acceptance. By doing this the company continually gains knowledge of new materials and cutting tools.

"We will be launching a new line of high-accuracy, highly productive machines this year at EMO (Machine Tool World Exposition, a European trade show for the metal-working industry)," Swanson told Orthopedic Design & Technology. "We expect this to change the industry standard. Key benefits of using this equipment include superior rigidity, high-speed linear motor drives and rigid, high-speed spindle (40 up to 60,000 revolutions per minute) with ham/mill function. These features improve reliability, extend tooling life and improve surface finish. The high-speed spindles are more robust and last longer. We also provide numerous options for the retaking of the part to finish the final face (sixth-face machining)."

In packaging, force sensing is a recent improvement where the actual compressive forces against the tooling face are measured in real terms to assist the packaging engineer with determining the exact parameters used to seal packages in the tooling. The development of sealing equipment, at a price point acceptable to the traditional medical device tray sealing customer, also has streamlined the process--including an all-electric sealer that provides very precise sealing forces that takes advantage of the existing precision tooling. The all-electric model was just released in 2012 and represents a fundamental change in how medical device trays are sealed.

Ultimately, one of the biggest challenges for the industry will be developing an ample supply of future manufacturing engineers and machinists.

"Think of the tools available to today's machinist and manufacturing engineers in terms of CAD/CAM software, tooling, machine capabilities, etc.," said MacDonald. "Then compare these capabilities to the 1960s and how easier it makes the machining of, say, a turbine blade for an aircraft engine. Then think back to the requirements and precision required of the Apollo program to assure multiple successful launches of the Saturn V rocket used to deliver our astronauts to lunar orbit. That is sheer talent, discipline and genus all in one. How do we continue to develop that level of talent?"

MacDonald believes that developing and maintaining an interest and passion for the art of custom manufacturing in future engineers is the biggest challenge facing the custom-machining industry today.

"Where are these talented people going to come from?" he asked rhetorically. "The ones that never give up and work smart with talent and persistence--the type that figured out not only how to machine those many precision Saturn V engine components, but actually did it with primitive- type tools relative to today's standards."

By Mark Crawford * Contributing Writer

Mark Crawford is a full-time freelance business and marketing/ communications writer based in Madison, Wis. He can be reached at mark.crawford@charter.net.
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Title Annotation:Machining & Tooling
Author:Crawford, Mark
Publication:Orthopedic Design & Technology
Article Type:Company overview
Date:Sep 1, 2013
Words:2629
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