Racing to Production with 3D-Printed Insert Tooling
by Dianna Brodine, managing editor
3D printing offers an opportunity to move quickly from design to molding to testing. Photos courtesy of Polymer Conversions, Inc.
Working to find value in the 3D printing process beyond prototypes and fixtures, the Natech Plastics team, including (foreground) Gary Bunch, senior mechanical engineer, and Domingo Hernandez, plant manager, is exploring the design options with 3D tooling.
A buffer chamber project was one of the first by Natech using 3D-printed inserts to create a molded part. Photo courtesy of Natech Plastics, Inc.
From left, Allan Baillo, an engineering intern from the University at Buffalo; Nathan Greene, process engineer; and Mike Swift, tool and die maker, are part of a team at Polymer Conversions focused on understanding the potential and limitations of 3D-printed insert tooling. Photo courtesy of Polymer Conversions.
The Boy Scouts Pinewood Derby project provided a model for the benefits of 3D-printed mold inserts. Photo courtesy of Polymer Conversions.
Two New York plastics processors are working to circumvent the extended lead times and additional costs surrounding the research and development process of new product launches. Both companies take great pride in the engineering technical expertise offered by talented employees, and both see the potential in using 3D printing to create insert tooling to increase the level of service offered to their customers.
Natech Plastics looks for a competitive advantage
Natech Plastics, Inc., located in Ronkonkoma, New York, opened in 1998 when Gerd Nagler started a molding facility focused on luxury cosmetic packaging. While consumer packaging still comprises 30 percent of the companys business, Natech Plastics has become increasingly engineering-driven. Currently, the ISO 9001:2008-certified company is a provider of custom injection molding and contract manufacturing focused on the medical, electronic and consumer markets, with a reputation for research-based experimentation.
The evolution of client support
Gerds son, Tom, now is the companys CEO and has been the force behind the switch to an engineering-driven production environment. Ive watched the industry evolve, he said. Transactional suppliers are at the lower end of the food chain, and customers expect greater value. Nagler admits the engineering services involved in a new design are his favorite component of the business, and the opportunity to secure client loyalty by becoming a supply chain partner that could fill a complex need appealed to him. In order for us to bring that design service to our customers, we had to be embedded in their businesses. It was very resource intensive for us, but it made us valuable.
Understanding the additive manufacturing landscape
Nagler has devoted time and resources over the last two years to watching the developments in additive manufacturing. As we talked about engineering services being a larger part of our business, we had to talk about how additive manufacturing would fit into that, he explained. It was never compelling to me for prototyping, because I can get that done with a service bureau just as quickly and at around the same cost. So, where did it fit?
Nagler went to a couple of additive manufacturing tradeshows, including RAPID, to gain competitive intelligence. Admitting that whats on a tradeshow floor isnt realistic, but rather a tradeshow version of whats possible, he nonetheless saw potential applications.
As were looking at what we want our business to be, part of the conversation was about what I had learned, he said. We had to decide: What do we want to do with additive manufacturing? We dont want to be a service bureau, so whats the value to us? And, whats the value to our customers? Its not that compelling of a story if we just print prototype parts. But, maybe there was some value if we could shorten the timeline or test out complex components. That was interesting, because it was sort of in our wheelhouse.
Mold building as a competitive advantage
Gerd Nagler trained as a master toolmaker before emigrating to the United States from Germany, but Natech Plastics outsources a majority of its mold building to other US toolmakers, applying Gerds knowledge to the relationships Natech has nurtured over the years. Working 100 percent domestically is an important differentiation point for Nagler, and he believes its a competitive advantage. Relationships are incredibly important to the mold building supply chain, he said. Every year, we specifically devote effort and time to find the right tool builders and develop the relationship with them. Its a critical part of our business.
Nagler explains this relationship because he isnt trying to replace tool makers with 3D printing. In the same way he offers an expectation of partnership from Natech Plastics to its customers, he also believes the mold builders his company works with are partners bringing crucial skills to the process. Instead, additive manufacturing technology could play a supporting role – and Nagler was intrigued enough to start a few experiments to better understand both the possibilities and the drawbacks.
The beginning of the experiment
We happened to have an urgent situation, said Nagler, before laughingly adding, Theres always an urgent situation! Natech Plastics was near kickoff for the steel mold build of a complex part that was one component of a larger diagnostics assembly, while at the same time another portion of the component was being modeled. Because of the difficulty of the build, Nagler knew a sample with a shorter lead time would be beneficial. We specifically chose something that was difficult, he said. We felt if the 3D insert printing process couldnt help us through something like that – geometrically complicated, with internal core pins and a detailed exterior – there wasnt value.
Nagler looked for a partner, and CADD Edge, a reseller of Stratasys equipment located in New York, was chosen to print the tooling inserts. By exchanging Natechs engineering and processing expertise with the 3D printing expertise of CADD Edge, the envelope of knowledge is pushed, and both companies benefit. Were building a database that tells us where the benefits are and where they are not, said Nagler.
It took three to four iterations to build a useful piece for the initial project, and Natech didnt beat the original lead time as the company had hoped because of the learning curve. Since the client hadnt been told a shorter turnaround could be possible, no one was disappointed – and the data gathered was a definite step in the right direction. We were able to confirm how much the part would shrink, which provided a good benchmark, Nagler explained. We also learned how to reduce ovality in cylindrical parts. Those are two things that are not exactly clear to begin with, and now we have that information in a database.
In the end, that first part wasnt all we wanted it to be, Nagler admitted, but it certainly wasnt a failure. Did it realize its promise? What were coming to believe is that the real sweet spot is not so much as a source of low-cost pre-production parts, which already is available in the market, but as a very powerful design tool allowing rapid iterations of risky design elements.
Natech Plastics completed a second experiment – this one a polypropylene application with a breakaway feature, one of Naglers so-called risky design elements. He explained: 3D printing the mold insert gives us a chance to test this feature out. We designed, printed and molded in the production material, and then we tested multiple iterations of the feature within days. Were not aware of any other technology that would allow us to move so quickly from design to testing.
The learning curve
Nagler admits the experiments have been fun, but the reality of getting a client to actually pay for it? Thats still unclear.
All of this is only meaningful if you are a design partner for your clients, not a molder, he said. However, we could either wait for other people to learn all there is about 3DIM – and then lose the value to our clients – or we could get the knowledge ourselves and create value. In the end, its still about the clients we chose and the strategy we put in place.
Natech Plastics is on the brink of an expansion plan, and Nagler and his team are deciding whether or not to bring additive manufacturing equipment in house. At the moment, I think the process has limitations, but we were able to adjust from one set of inserts to the next because were processors and mold builders. Our engineering expertise gives us an edge.
The technologys other applications may swing Nagler toward the investment, including the ability to print fixturing or a prototype on occasion. Its the potential, however, that is truly exciting. Its why I come here every morning, he said. Were a learning organization, and this is a new area for us to explore.
Polymer Conversions takes its knowledge to the derby
Some 400 miles to the northwest, in Orchard Park, New York, the team at Polymer Conversions, Inc., is engaged in a similar investigation. Polymer Conversions opened its doors in 1979, and one of its earliest projects was molding the plastic eyes for Kermit the Frog toys. Today, engineering and tooling expertise, combined with ISO 9001:2008 and ISO 13485:2003 certifications, have positioned Polymer Conversions as an innovator in the medical device, health care, pharmaceutical and aerospace industries.
Reducing the costs of R&D
Were a high precision molder, explained COO Ben Harp, and we like making parts with critical dimensions. Those dimensions lead to very expensive tools. One of the things that deters research and development is the cost to look at different design concepts and make changes, but the advent of 3D printing has shifted the landscape. Now, OEMs can hold design possibilities in their hands – they can feel the part and connect their thoughts and concepts to reality.
Prototype printing, however, has its drawbacks. Specifically, material limitations often mean the 3D-printed part is not created from the intended material as specified on the print, so chemical resistance and strength characteristics do not match. The perfect scenario would provide samples with the faster speeds and lower costs offered by additive manufacturing technology, but that could be used for early stage clinical trials. Polymer Conversions began to explore the possibility of 3D printing the tooling inserts, rather than the end-use part, to create the geometry needed in a shorter time frame without compromising the base materials.
To aid in the discovery process, Polymer Conversions appointed a team focused on understanding the potential and limitations of 3D-printed insert tooling: Dan Schwab, lead mold designer; Nathan Greene, process engineer; Ryan Gillon, process engineer; Mike Swift, tool and die maker; Leanna Bradley, quality engineer; and Alan Baillo, University at Buffalo intern.
Learning the limitations
The best case scenario is to have the ability to take the customers design, print an insert tool within 24 hours and drop finished molded parts into the mail for the customer 24 hours after that, said Schwab. What were attempting to do is great in concept, but what can we really achieve? Will it work in all materials, and what are the tolerances we can hit?
Much like Natech Plastics, the team at Polymer Conversions is focused on data collection. There are questions about cycle times and how much heat and pressure can be applied before the insert blows apart. What we hope to accomplish in this exercise is to better understand what can be done, to what tolerances and resulting in how many parts, so we can coach the customers in what to expect, said Greene. For a very low cost, we can get them further down the design path in product development or a small-volume application. We add significant value by saving the customer time and money.
Investing in the possibilities
Polymer Conversions does not have 3D printers on site; instead, the injection molding company partners with Staub Additive, a high-tech organization only four miles from its plant. Our toolroom is capable of building every tool we supply to our customers, said Schwab, but were prioritizing the support of our production floor for existing tools. At some point, we may invest in additive manufacturing equipment, but now it makes sense to work with a company that already has the equipment and the expertise in 3D printing.
Harp explained, What were trying to do is take our affinity for learning things and applying technology we already know well to benefit our industry sector. Medical device companies are having early stage success validating 3D-printed medical devices, but you can count those FDA approvals on one hand. We think this is a step better because were using legitimate production resins. In medical manufacturing, the faster we can meet our customers needs – safely – the faster their devices can be put to use.
For one of its first projects, the team chose a part it has been molding in the conventional manner for 10 years. The learning process will come with an extensive paperwork trail that includes timelines, costs, tolerances and run sizes. Steel, aluminum and 3D-printed tooling will be compared in great detail to provide data the Polymer Conversions team can use to then prove results with the customer.
We know exactly what we can do with eight-cavity tooling, said Greene. We know exactly what the part costs to build in the highest quality materials and in less expensive materials. And, we know which materials have been successful. Now, well try out production with insert tooling, and well learn.
To date, the teams internal science project has produced approximately 300 parts and endless amounts of data. Swift detailed some of the experimental processes, including ramping up the clamp tonnage and testing various venting methods. We were concerned about the plastic cracking or collapsing, but it made it to 50 tons, which was amazing considering we were going up against plastic.
Greene added, The actual 3D-printed cavity finally cracked and started chipping at 300 cycles at about 50 tons. For low-volume production, 300 pieces could very well be enough for an entire year for some customers, but it was important to know when that cracking began to occur.
In fact, said Swift, the results have been impressive, even on a small scale. Coming from a tooling standpoint, the 3D-printed tool held up very well, considering the fact that it was a plastic part molding a new plastic part.
The team continues to emphasize that the process is what is important right now. Were documenting everything we do, said Greene. We keep 99 percent of the parts every time, even if its a bad part. Then we label it and document what happened during that test so we can learn whats possible.
Playing with the possibilities
Engineers and mold builders, however, cant be given access to new technologies without expecting a little side job here and there. Enter the Boy Scouts of America Pinewood Derby® project. The first derby was held in 1953 and, although kits are sold by the Boy Scouts to ensure similarity of materials among competitors, an open class allows modifications – including those to the wheels.
Swift was enthusiastic about the possibilities, which included machining some of the plastic for improved tolerances and better shutoffs. We had a few things we were going to try, so we could make them the fastest cars around, he laughed.
What started as a fun project for a local troop and the son of a Polymer Conversions employee became the poster child for the benefit of 3D insert tooling. On the first tool we created for this project, said Harp, we gated into the outer part of the wheel surface that would be in contact with the racetrack – and we realized what we had done right after we molded our first part.
After we laughed and shook our heads, he continued, we were able to make a quick part design change and were back in production within 24 hours. Sure, its a funny story, but it also proved the benefit of what we were trying to do. The ability to test designs and make adjustments almost immediately could be a game changer, and its exciting to be at the front of the learning curve.