����ý

“We are not a quarterly company,” says Denny Reiland, third-generation owner and CEO of Minnesota-based manufacturer . “We are a decades company.”

That long-view perspective has shaped General Pattern’s evolution over its 103 years, from its founding in pattern making to its current role as a custom plastic specialist.

Featured Content

How Vacuum Drying Is Revolutionizing Plastics Processing READ MORE

ColorForm From KraussMaffei Brings Key Competencies to One System READ MORE

AI-Driven Capabilities Advance Efficiency and Quality in Your Molding Environment READ MORE

Where other long-tenured manufacturers might have become hesitant or stagnant, General Pattern has embraced change and reimagined itself multiple times over the decades. That reimagining has sometimes meant abandoning markets that no longer make ����ý sense. But it has also meant bravely stepping into new ones, and adopting the right technologies to serve them.

Additive manufacturing (AM) is one such technology. While General Pattern has been using 3D printing for prototyping since the 1980s, the company held off on deeper implementation of AM until the technology felt more mature. Today, General Pattern has embraced several types of additive manufacturing to produce tooling for its injection molding services, alongside conventional moldmaking. I visited the company’s Minnesota campus late last year to learn how General Pattern is applying 3D printing technology to support its tooling needs today, and the role AM could play in its future decades.

Molding and Moldmaking, Vertically Integrated

General Pattern has seen plenty of change in its century-plus history. The company, founded in 1922 by Reiland’s grandfather, began as a pattern-making ����ý to support foundries. When casting work began moving overseas in the 1970s, the company took the skillsets it had acquired in pattern making and pivoted into the related field of model making, this time for the toy industry.

That pivot also brought about an acceleration in the company’s typical delivery timelines, as toys typically go from concept to product in stores in less than a year to meet the holiday rush. Driven by customer needs, General Pattern soon jumped from model making into injection molding of parts to support the toy market. Keeping up with the pace of product development also necessitated producing the mold tooling to be able to deliver parts within a matter of weeks.

Supporting product development has continued to be a significant part of the company’s activity. General Pattern adopted its first 3D printer in 1987 to help automate modeling and keep up with demand for rapid product development and prototyping. This responsiveness and willingness to iterate quickly with customers on new products has remained a core capability, even as part-producing through injection molding has grown to the largest share of the company’s ����ý, supported today entirely by tooling made in-house.

Product development is a step on the way to winning the scale production work, and beginning to collaborate with the customer on a new product or part in its prototype stage helps with the workflow later, when “we have to live with production,” Reiland says, explaining that this collaboration entails not just working out technical details but establishing trust as well. “Part of prototyping is the relationship that we build.”

The Long View Looks Toward Additive

The road from pattern making to vertically-integrated injection molding hasn’t been a straight one, but over the last few decades molding has proven to be an enduring ����ý. With each new customer and opportunity, General Pattern aims to take the long view. Rather than quick transactions, the company embraces opportunities where it can become a long-term production partner for the customer, ideally for multiple projects.

“Once the trust is earned, we work with the customer to support the multiple needs of our wide breadth of service,” Reiland says, describing how one job frequently leads to more with established customers. It’s been a successful strategy; the company’s top 10 customers have all been using its services for more than 20 years.

Longevity carries through within the company as well. Today, Reiland works alongside his daughter Staci Thill, president and part of the fourth generation of family to lead the ����ý. Average employee retention is 14 years, and some employees have even been with the company since the pattern-making days.

General Pattern currently occupies 18 buildings in Blaine, Minnesota, and also owns a plant in Indiana. The company’s 85 molding presses cover injection molding at all scales — low, medium and high volume — as well as urethane casting, foam injection molding, rotary molding, and various finishing operations including painting and assembly.

On top of all this, the company continues to manufacture all its own tooling in-house. The company operates 62 CNC milling centers, many of which are dedicated to producing mold bases, cavities and inserts. Of its 200 employees, 10% are full-time toolmakers.

These experienced professionals have been incredibly important to General Pattern’s growth and ability to quickly develop and produce molded products. But the toolmaking workforce is aging, and there aren’t enough young people in training to fully replace what will be lost when they retire. Therefore, General Pattern has been keenly watching new technologies including computer vision and 3D printing to bridge potential gaps and shore up its capacity for the future.

3D Printing As the Toolmaker’s Reinforcement  

General Pattern is farthest along with the latter technology, 3D printing, as an augment to its existing toolmaking workforce and capacity.

After watching the market for some time and experiencing frustration with laser powder bed fusion (LPBF) tooling for its postprocessing needs (“If you gotta cut it anyway, you might as well cut it to begin with,” Reiland says), General Pattern made the decision to invest in a different metal 3D printing platform from Mantle.

This machine in its soft green state; upon sintering in a separate furnace, a printed mold insert made this way can often go straight into a tool, without finish machining or further processing in many cases.

“Moldmakers are a finite resource,” Reiland points out. The addition of the metal 3D printer was a way “to help get more throughput.” And moldmakers have taken to this tool, leveraging it for everything from quick-turn prototype and production molds to inserts for larger tools and design iteration of specific features. (One of the operators of the Mantle platform is actually a pattern maker, someone who has been with the company since before its multiple waves of reinvention.)

A 3D printed tool is generally comparable in cost to one made conventionally, Reiland says. But where the Mantle process shines is making not the full mold, but its most complicated parts — the smaller inserts that provide the detail of the finished part — while the cavity and larger pieces are machined, effectively stretching the capacity of toolmakers. Meanwhile, TrueShape also offers speed; a complete H13 tool steel insert can be produced in just a week, with “amazingly minimal handwork,” Reiland says.

General Pattern actually had the chance to put the process to the test against conventional toolmaking for the mold pictured below. This tool for molding the A-pillar of a truck was initially produced using sinker EDM to create the deep ribs, and features 31 hand picks (or sliding elements for undercuts or recesses). Four toolmakers completed the core, cavity and inserts in about four weeks with about 400 hours of labor. But when the customer came back with an updated redesign, it meant rebuilding the tool from scratch. 

This time, General Pattern leveraged the Mantle technology for the hand pick inserts. These pieces took 110 hours to print and 48 hours to sinter, time that mostly left the toolmakers free to focus on the core and cavity. No secondary operations were required on the 3D printed inserts before use. Producing the tool the second time around required only 200 hours and the work of just two toolmakers.

A Dual-Tooling Strategy

While the Mantle platform has been a boon to General Pattern’s toolroom, early product development requires a different technology. The company more recently has been exploring polymer 3D printed tooling using , a technology developed by AddiFab and currently available through Nexa3D.

FIM involves 3D printing mold tooling using Nexa3D’s resin-based 3D printing platform; rather than a permanent tool, however, FIM produces dissolvable, one-time-use tooling. And the platform is fast — a tool can be printed in just one day on the Nexa3D desktop machine that is suitable for use with an 8-ton press. The technique makes it possible to mold parts with complex internal structures, overhangs and geometries that would not be viable with standard injection molding, even during the early development stages. 

For General Pattern, the technique also has the advantage of being a fast, efficient path to prototype tooling that is compatible with typical molding materials. The Nexa3D solution offers a way to easily and quickly iterate the product design before cutting (or perhaps 3D printing) a metal tool, allowing prototypes to be made from the same material intended for production. This is particularly useful for customers such as medical device companies; a quicker path to molded parts can accelerate the FDA approval process.

But FIM’s speed pays off for various types of product development. For example, in one instance an engineer from a customer company traveled to General Pattern to see initial prototype molded parts for the chin strap buckle for a child’s helmet but found that the engagement of the buckle wasn’t quite right. He went back to his hotel room to make some CAD adjustments and sent a new design to General Pattern, which then printed new tooling with Nexa3D, and assembled and shot the mold to produce new prototype parts within 24 hours.

Beyond speed, FIM also offers new ways of approaching difficult molding geometries, especially when used in combination with Mantle-printed tooling. This mold for an earbud component is an example.

Undercuts in the design required hollows in the tool, which were difficult to 3D print unsupported with the Mantle process. After struggling to achieve the exact geometry with metal printing alone, General Pattern implemented Nexa3D FIM to make smaller lifters that can mold the undercut features as part of the same tool. When the FIM lifters are dissolved out later, the overhang is left standing.

AM for Tooling — And Beyond

With 3D printing capability, General Pattern provides 16 different tooling categories to support injection molding in its separate low, medium, large tonnage  and high-scale volume facilities. Tools range from early development and short lead time (the Nexa3D FIM tooling) to the most complex and longest-lived (full steel). General Pattern aims for “volume optimized tooling” (VOT) whereby the selection of tooling material and strategy is matched to the expectation of annual use and longevity of the program.

“We consult on the program and lifespan to match our proposal to best fit the needs of the project and ROI,” explains Marcy Krosch, senior vice president of sales. Sometimes needs change, in which case tooling can be remade or adapted; lower-cost aluminum tooling initially made for smaller volumes can be treated with a Teflon-nickel coating to extend its life rather than remaking the tool in steel, for example.

“It depends on the quantity, material, timeline and life of the part,” Krosch says. “Having multiple solutions to offer helps us problem-solve with our customer, which is another of our advantages.”

Skipping tooling altogether in favor of production through 3D printing may become a more significant one of those options in the future, though direct printing of parts is only a small part of the ����ý today. For quantities of more than 500, General Pattern finds that injection molding, with tooling made through one of its internal processes, is still the way to go. Currently General Pattern offers 3D printing services only to existing customers, and most of this capacity is still dedicated to tooling and functional prototyping.

Its HP Multi Jet Fusion 3D printer, for instance, is almost completely dedicated to quick-turn prototyping for clients. For example, a power tool company that frequently iterates new products on a 15-day timeline, has a standing order for time on the machine; each day General Pattern starts a print around 4 p.m. and ships the parts the next day. “Our sense of urgency is the secret sauce,” Reiland says.

Production through 3D printing might look like more of this work: fast, responsive manufacturing to provide small quantities of parts right away. It might also be a way for General Pattern to deliver aftermarket parts or components needed only on an intermittent basis.

The company is currently building a library of parts like this using software from Dozuki. For parts designed or adapted for 3D printing that are stored in this database, AM could be a way of filling some of these needs in the future. 

“We’re in the process of graduating 3D printing into production,” Reiland says. Currently, there is no immediate rush to jump into direct additive manufacturing of polymer parts. But if the demand comes, and the technology can meet it, General Pattern remains flexible and ready to pivot.

About the Author

Stephanie Hendrixson reports on 3D printing technology and applications as executive editor for . She is also co-host of , a video series that highlights unique, unusual and weird 3D printed parts, and co-host and creator of the .