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Armstrong Rapid Manufacturing

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Upstate New York Firm Offers Prototypes and Low-Volume Parts for Medical Industry

Low-Volume Parts for Medical Industry

Offering services focused on rapid prototyping and short-run production, as well as offering parts in both metal and plastic, Armstrong Rapid Manufacturing fulfills a niche demand for the medical industry, which is often seeking low-volume production and over-molded parts. While Armstrong serves many industries, medical is one of the company's biggest markets, as it supplies mostly parts for diagnostic equipment.

As an ISO 9001:2008 certified company, Armstrong offers a breadth of capabilities in manufacturing parts in both aluminum and polyurethane plastic. The company also offers services to suit product manufacturers doing prototyping, product development, and short-run production. "We offer a seamless transfer from developing a product, making changes, and then getting it into production," said Armstrong's director of sales, Paul Armstrong.

Where worldwide demand for a medical product might be only in the hundreds, the medical industry is interested in a supplier that can accommodate manufacturing only a few hundred units a year while offering cost savings and high quality. Low-volume manufacturing, which the medical industry is focused on, is more like "prototyping on steroids," Armstrong said. That's where Armstrong's rapid prototyping services, as well as its range of capabilities to make quick-change, low-cost solutions to design challenges, come into play.

"Our company's mindset is quick turnaround, and we have processes that are there to serve people in product development. One of our most important features is the way we go about making parts," Armstrong said. "We can accommodate design changes on the fly. If they do an analysis in their lab and realize they need to change a feature, it's really easy for us to go in and change a feature in our molds because we're not making molds out of steel, like they do in production, where they can't make a change. We can easily change geometric features as the design evolves during a product development cycle."

With a business model that for 40 years has been built around prototyping and low-volume production, East Syracuse, N.Y.-based Armstrong Rapid Manufacturing helps customers take their design and concept and make it easier to manufacture, Armstrong said. "We're trying to make it a more robust design and, at the same time, the lowest-cost design they can get while still giving them all the capabilities that the design would need. Medical companies know their technology very well, but what we try to do is be experts at manufacturing, so we try and guide them on that and how it will impact their cost and quality."

One option Armstrong offers that saves money upfront and shortens lead time is one-shot casting, where the company is able to make aluminum castings without the tooling.  "We're able to make one to ten prototype aluminum castings without tooling expenditure and get them parts in about a week for casting because it not only cuts costs, but timing," he said. Plaster molds are poured directly from laser-sintered models, which are burned out of the mold after the plaster has set. "We're eliminating tooling, which eliminates a step and you just get a part."

One medical customer came to Armstrong with a design challenge to overcome radio frequency interference. The customer needed to create an RF shield and Armstrong was able to create the part using one-shot casting. "We made one very quickly in a week or two. We provided a quick turnaround and were able to test out their idea at a low cost in a quick time frame," he said.

Medical customers are striving to make products that are more technologically advanced, less expensive to produce, and smaller in general, said Armstrong. While medical products are tending to get smaller, leaner, and more efficient, many diagnostic machines are larger pieces of equipment. That means they're more expensive to ship and parts are more expensive because they're bigger. "So anytime you make things smaller, it's more economical to manufacture because the parts aren't as big and are not using up more material," he said. "By making things smaller, prices will be driven down in general. There will be lower shipping costs, less material, less floor space taken up, and less storage costs."

Parts for diagnostic equipment are a growth industry for Armstrong Rapid Manufacturing because the demand for new medical equipment is being driven by an aging population and advances in medicine. "The medical field is exploding, and they need the equipment to support all of that new medical technology," Armstrong said. "This equipment is being used for both testing and procedures."

Offering parts in both metal and plastic benefits the customer because Armstrong is able to provide multiple parts and capabilities from one supply source, so the customer doesn't have to seek out several suppliers to get one part made. "In the prototyping mode, we're also able to try things in plastic and aluminum to see which is going to give them a better performance," Armstrong said. "All we want is for them to get the best possible solution to their design problem." Many times, the company can make a metal part that has been over-molded in plastic. "The medical industry is big on that because there are usually all kinds of hidden components and there are strength and insulation issues," he added.

Other capabilities Armstrong offers are rubber plaster molding, air set sand castings, graphite mold die casting, and reaction injection molding (RIM). Rubber plaster mold replicates the appearance and physical properties of a die casting. "It can either replicate a die casting for low-volume, or if someone is ultimately going to go to a die casting, it gives them a good, cheap, and quick way to test and prove it all out before they invest in the die cast tooling," Armstrong said.

Air set sand casting is used for larger, thicker walled castings. "There's a lot of application for that in the medical industry where they need something that's sort of a larger, bulkier part. We actually take a cast base that we do in sand casting and overmold plastic over it so it looks like a plastic part," Armstrong said, explaining that it is used frequently with portable defibrillators because they want the look of plastic while having the heavy metal weight at the bottom.

Because the graphite mold die casting is ideally suited for making 100 to a few thousand parts, it is applicable to the medical industry, which doesn't usually have the volumes to support true die casting. "Processes like plaster mold become very expensive and cost restrictive to them," Armstrong said. "Graphite molding is similar to die casting except we make a die or mold out of graphite, instead of steel. So we're able to make the same mold over and over and get much shorter cycle times, which makes the piece price cheaper," he said.

With reaction injection molding (RIM), the company is able to produce parts with intricate detail that are dimensionally stable, chemically resistant, physically tough, and wear resistant. It is suited for larger plastic parts produced in short run or low volume production quantities. Reaction injection molding is used with medical diagnostic devices and for medical enclosures because it can accommodate thick and thin-wall sections that would not be suited for injection molding. Thermosets, polyurethanes, or foamed polyurethanes are used, and because of the low viscosity and low injection pressures, large, complex parts can be produced economically and in low quantities.

This technical information has been contributed by
Armstrong Rapid Manufacturing

Click on Company Name for a Detailed Profile

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