It All Adds Up
Additive manufacturing is bringing drastic change for the better to theorthopedic prototyping process.
It is an exciting time to be involved with orthopedic rapid prototyping. Technology is advancing to the point where the process is getting faster and more accurate, and in some cases the end results can perfectly resemble production pieces. Indeed, in the past year, the U.S. Food and Drug Administration (FDA) has begun to approve devices for use in the field manufactured with processes that previously were considered to be strictly for prototyping.
This means there are more reasons for orthopedic OEMs to make rapid prototyping part of their product development processes. It also means that it is in their best interest to find a partner, whether a contract manufacturer or a prototyping specialist, that can help them reap the advantages of the new technologies that are revolutionizing the process.
“There seems to be a trend with some manufacturers of establishing and leveraging supplier relationships versus making large capital investments in equipment and the personnel required for operation,” said Daniel Anderson, manager of prototype technology and design for Greatbatch Medical, a contract manufacturer based in Clarence, N.Y. “Companies are trending toward partnering with suppliers for concept development and prototyping.”
What follows is a depiction of some of the technologies driving the rapid prototyping market, and the advantages they offer to orthopedic OEMs.
DMLS and EBM Change the Game
Many orthopedic prototyping applications are moving from conventional machining and injection molding to additive technologies. Many additive technologies use Direct Metal Fabrication (DMF), and the most touted form of DMF is Direct Metal Laser Sintering (DMLS).
“The orthopedic market is experiencing an increased emphasis on speed in bringing new products to market. Accordingly, in the product development area, one of the hottest trends is the use of (DMF) earlier and deeper in the concept/product development process,” said Anderson. “DMF is generally defined as a process that fuses metal particles—usually in powder form—together versus standard machining processes. The DMLS system that we employ uses a laser to fuse metal powder into a part in 20-40 micron layer thicknesses.”
This means that prototypes now can be made with materials that are the same (or close to the same) as the ones used to make the devices themselves.
“Service bureaus can `print’ parts, similar to the previous-generation Selective Laser Sintering (SLS) process, in materials that were not previously available,” said John Vargas, engineering manager for Pro-Dex Inc., an Irvine, Calif.-based contract manufacturer and designer. “These new materials include plastics and metals that now conform or are close to conforming to ASTM material specifications. Some companies are already using this process to directly `print’ custom parts for use in medical applications such as [knee] implants. These parts can be modified using various secondary processes, and can be finished with a variety of coatings depending on the application.”
Recent advances have improved the laser sintering process for stainless steel applications, which could have tremendous implications for orthopedics, said Shane Collins, managing director of Directed Manufacturing Inc., a Pflugerville, Texas-based rapid manufacturing firm.
“The latest development in prototyping for orthopedics is the development of 17-4 PH stainless steel using the laser melting process,” he said. “Until a recent breakthrough, surgical instruments and trial components made with 17-4 stainless steel in the laser sintering process would not harden like the wrought material. Device designers and engineers no longer have to compromise with 15-5 PH stainless steel when the industry standard is 17-4 PH.”
Tim Ruffner, vice president of new business development and marketing manager for GPI Prototype & Manufacturing Services Inc., a Lake Bluff, Ill.-based service bureau specializing in additive technologies, noted that DMLS has become a particularly valuable technology for making products to be used in clinical trials.
“DMLS and SLS are some of the newest technologies that mimic closely to production-grade materials that can be used for rapid prototyping,” he said. “DMLS produces metal components that meet ASTM standards for metal composition and SLS is great for cutting and/or drill guides used during surgery.
Indeed, more and more companies are choosing to use DMLS as production for trials and devices to use in surgery. For example, DMLS is perfect for femoral trials. We have had great success working with Consensus Orthopedics on these trials. What makes this perfect is that we can create the trials in a stainless steel material in several sizes for both left and right knee condyles. During surgery the surgeon can use the trial for fit and function before putting the implant into the patient. This saves thousands of dollars. Where DMLS trials can cost a couple of hundred dollars, the implant costs thousands.”
The level of customization made possible by DMLS has the potential to revolutionize the orthopedic industry, according to Patrick Pickerell, president of Peridot Corp., a prototype manufacturer based in Pleasanton, Calif.
“Laser sintering of net shaped ortho implants is a rapidlymaturing technology,” he said. “This additive process coupled with3-D scanning of the patient’s anatomy are leading to a future where implants will be custom-produced on a one-off basis that exactly match the patient’s anatomical structure.”
Another advantage of DMLS is that it can greatly reduce the time it takes to produce a prototype and allow for more iterations to be completed in a given time frame, said Anderson.
“OEMs are beginning to understand the value of this technology beyond the obvious of just creating prototype or ‘show and tell’ parts,” he said. “Instruments produced with DMF are being reviewed in metal earlier in the process and are being tested in cadaver labs and, in some cases, live surgeries. Prototypes are generally critical path items, so DMF provides an avenue to prototype faster and/or with more iteration in a given timeframe. Of course, time and money savings by exploiting DMF technologies vary by situation, but there are times when these technologies can produce a prototype overnight that would take weeks to produce with standard metal removal technologies. In product development, time is money, so providing a faster product at a cost that is not necessarily cheaper will often result in long-term savings. The balance of time/money savings depends on the customers’ situation.”
Another additive technology making inroads is electron beam melting (EBM). As with DMLS, the FDA recently has approved certain products manufactured with it, so while it is not just for prototyping anymore, its use in prototyping gives orthopedic OEMs an extremely accurate precursor to what their devices will look and feel like.
In EBM, a metal powder is used to build layers of dense metal, which then is melted by a high-energy electron beam. Each layer can be melted to an exact geometry dictated by a 3-D CAD model.
“One of the reasons why DMLS and EBM have been used with FDA-approved products is that you can guarantee the density of the material when you cut it,” said David Olmsted, sales manager for Mark Two Engineering Inc., a contract manufacturing firm based in Miami, Fla. “Certain emerging technologies are gaining tremendous traction because of this.”
As a result, OEMs are better able to integrate prototyping with production, which gives them a tremendous advantage, according to GPI Prototype’s Ruffner.
“Because we can prototype the part in a material that best suits the customer’s needs and they find it works well with their project, they can go into additively manufacturing with the same process,” he noted. “This is great because it saves time and money. We have several customers in the orthopedic industry that use our processes for additive manufacturing of parts along with prototypes.”
But one thing that was holding back additive manufacturing is about to go away, said Collins.
“A limitation to the additive manufacturing industry has been a lack of standards that allow a purchaser and supplier to easily agree on component attributes,” he said. “Now that the ASTM F 42 Committee is developing these standards, that is going to change. Whether an additively manufactured component is for a prototype or production application, there will be standard specifications that have to be met and this will facilitate more transactions.”
Help With Timelines
Additive technologies are becoming attractive to orthopedic manufacturers because in recent years there has been extreme pressure put on the product development timeline.
“The clamor for impossibly short lead times irrespective of cost has now become cacophony,” said Pickerell. “Two- to three-week lead times impress no one in our market. Creative staffing and very tight scheduling are the keys to success here. There is no room for error.”
The FDA approval process has been taking longer, so in order to get a time-to-market advantage, firms need to get from concept to FDA submission more quickly.
“Compressing time to market has always been an important factor, but this has definitely increased over the past few years with increasing competition, and delays in regulatory approval,” said Vargas.
“To stay competitive, customers need their products to be delivered at a much faster rate—with high quality, precision, reliability, and lower cost. We address this through value engineering, concurrent engineering, cross-functional collaboration at the very start of the project, an emphasis on DFM (design for manufacturing), DFA (design for assembly), and lean manufacturing and collaborative communication both in-house and with our customers.”
If the prototyping process can take less time than it usedto without sacrificing accuracy and verisimilitude, that is asignificant benefit.
“Many customers continue to see internal resource restraints and various barriers to a fast development process. They areseeing the value in working with us earlier in the product development process—e.g., design and concept development phase—which then dovetails nicely with our expertise in exploiting new technologies for producing prototypes,” explained Anderson. “We’ve had recent situations where we started with a napkin sketch, designed an instrument and had a working prototype in a couple of weeks. From there, we refined the design from the prototype phase to a product that could be easily mass-produced. Some customers are becoming somewhat accustomed to the shorter lead times that can be achieved with the new technologies, and expectations have changed accordingly. Prospective customers often request lead times that generally could not be achieved with ‘standard’ technologies. It is important to know the technology options and the best ways to exploit them to help customers achieve their goals.”
Ruffner agreed.
“Additive manufacturing is taking a turn for the best in today’s economy,” he said. “Nowadays you can get parts created without any tooling and reduce your lead time significantly. A couple years ago there were SLA (stereolithography apparatus) systems on the market everywhere, now it’s hard to even find an SLA machine for sale. What does that say about the manufacturing technology climate? I think it says a lot.”
Vargas said more customers are asking Pro-Dex for prototypes earlier in the product development process, and their demands are for good reason.
“To ensure customer needs are nailed down before the design and its test protocols are developed, a trend, at least with Pro-Dex, is to create a ‘functional’ prototype while still in the feasibility stage,” he said. “This is a bare-bones, primitive prototype of what the customer is requesting. Making prototypes much earlier gives the customer or potential customer something to see and feel. This helps guide more constructive conversations with customers because they are based on an actual model, not on one- or two-dimensional drawings. This helps the supplier ensure they are on the right path, and gives the customer confidence that the supplier clearly understands what they are wanting.”
Olmsted cited similar experience with additive manufacturing.
“We are trying to push rapid prototyping and additive manufacturing at the RFP level,” he said. “If a product design engineer has a concept, with additive manufacturing, you can try multiple different ideas in one shot, seeing how it looks in 3-D with a relatively quick turnaround. For example, if you have three different handles you are considering for your design, you can put out three different versions using additive technology without having to do retooling or reengineering.”
Collins notes that thanks to the increased popularity of additive manufacturing, “there is increasing demand for integrating additive manufacturing into conventional manufacturing processes. The additive processes are becoming another tool like injection molding and computer numerical control (CNC) machining to deliver customer-driven solutions.”
Another byproduct of the technological advances, Collins said, is an increased interest in linking prototyping processes withproduction ones.
“Customers are looking for prototype technologies that can transition into production where design for manufacturing guidelines are not a concern,” he said. “Now, hundreds of total knee replacements are performed each day where cutting and drilling guides are made custom to patient anatomy through the additive manufacturing process. As the materials in the additive processes mature, more and more components will transition from prototype-only into production, maintaining complex designs.”
Another demand is for instant quotes, often online, said Ruffner. Many prototyping firms can pull these off, but OEMs need to make sure they have all their bases covered if they are going that route, he cautions.
“The newest trend for prototyping jobs is the fact of getting instant or online quotes, which saves time for the engineer,” he said. “The biggest concern with this trend is the fact that while online quoting saves time, the actual technician that will produce the parts doesn’t look at the actual model to see and help with any design changes for the process. What happens is the engineer will complete the order online, receive the parts and become unhappy when they receive parts that they thought would be to their spec. We have worked very closely with our customers and we will make sure that we talk about the project to the fullest before production.”
Indeed, said Justin Creel, Ph.D., director of product development and marketing for Consensus Orthopedics, an orthopedics OEM that has worked with GPI, it is not speed but the quality of earlier work that is his top consideration when picking a partner for a prototyping job.
“The most important factor in determining who we are going to work with on future projects is prior performance,” Creel said. “Were they easy to work with? Did they perform as promised? Were there any problems? Did they solve the problems quickly and efficiently? After those considerations, price and turnaround time are probably the next most important considerations.”
Help With Costs
No discussion of a manufacturing process is going to be complete without consideration of costs. Some OEMs might be cautious about working with new technologies that require new capital equipment, but there are ways around that if they find a partner who already has it. And they also must consider that more efficient technologies could reduce costs in the long run.
“Once the initial investment of capital is made, significant costs can be saved in product development, because you can go from concept to reality much faster,” Olmsted said.
Ruffner said he understands OEMs’ concerns there.
“There are a lot of companies out there that are low cost, but these companies sometimes put a bad name to the good companies, because low cost often produces low quality,” he said. “Choosing low-cost prototypes isn’t always your best bet. Numerous times I have seen upset customers because they purchased a low-cost prototype and ended with a low-quality part. The implications for us are that not only are we constantly looking for lower cost materials, but if we can help with a little longer lead time to help utilize the build envelope and its scales of economy, that also helps customers reduce costs.”
The ultimate cost of rapid prototyping often comes down to how efficient an OEM’s product development process is, said Vargas.
“The best way to keep costs down is being very clear upfront as to what the customer wants and what the real-world application of the device will be in the field,” he said. “New technologies can sometimes help keep costs down, but it really comes down to a company’s processes. The more efficient and streamlined their processes are, the lower costs are overall.”
One place where a supplier can help is by having sophisticated machinery that reduces the number of steps involved, said Pickerell. This already exists at a number of machining operations.
“Multi-axis CNC machines that can cut down on or eliminate time-consuming and therefore costly secondary operations are mandatory in today’s ortho market,” he said.
The same eventually will be true for additive technologies, said Directed Manufacturing’s Collins.
“Common to the additive manufacturing process are machines that run autonomously with little operator intervention. Often, one operator can set up and operate many machines,” he said. ”However, when the components come out of the additive manufacturing machines, there are significant manual operations that require too much bench time. What will keep costs down in the future are technologies and processes developed specifically to address these post-processing operations.”
Partnering for Success
No two prototyping projects are alike, so one thing OEMs must keep in mind is that there is a benefit to choosing a partner who can offer a multitude of options from a technological standpoint.
“If all you have is a hammer, everything looks like a nail,” said Anderson. “Being familiar with only a short list of technologies limits the ability to benefit customers’ projects in the best way possible.
Suppliers with knowledge and access to a broad range of technologies can provide the best service to their customers. It is not unusual at all to see concept models and prototypes that incorporate components produced with several different technologies.”
OEMs also should get as many of their departments involved in the project from the beginning.
“Concurrent engineering is so key,” said Vargas. “For a fluid, efficient progression from design to manufacturing, it is critical to bring engineering, RA/QA (Regulatory Affairs and Quality Assurance), manufacturing, procurement, and business development together at the same time, at the very start of a project. Bringing these multidisciplinary perspectives together from day one results in better ideas and solutions and eliminates unnecessary steps, set-ups, materials, and restarts. Early discoveries of these issues allow for team members to flexibly arrive at alternative solutions and make adjustments that will work better for both design and manufacturing before the project progresses. Adaptability and flexibility are what exposes and resolves issues faster, improves quality, eliminates waste, reduces the time it takes to finish a project, and minimizes cost.”
And companies should involve their partner early on, too, according to Pickerell.
“Early stage discussions with your contract manufacturing partner is critical to avoiding mistakes and delays downstream,” he said. “Take advantage of the many years of experience that your supplier has by discussing materials, shapes and your projected build schedule as early as possible in the development cycle.”
If that is done, OEMs may end up with a rapid prototyping process that is orders of magnitude more efficient and effective than what they have been doing.
“We want our customers to think outside of the traditional machining box,” said Olmsted.
Eric Swain is a freelance writer based in Phillipsburg, N.J. He hascovered the medical device industry for 13 years.