From Volume 2 Issue 1 of Connected.
The manufacturing process involves a lot more than the production of a single assembled product and its parts. At the heart of the process is the machinery doing the work. That machinery is what produces the parts for the final product through a series of designing, engineering, cutting, shaping and forming of materials known as machine tooling.
Often the components created through tooling are custom made and require molds, toolmaking and time. Production lines don’t have time to wait on machine components when the line is down. Additive Manufacturing, or 3D printing, allows the manufacturer the ability to print spare parts and tools when needed to keep the line up and running.
Two of our manufacturing business units — Kirby Risk Service Center and Kirby Risk Precision Machining — have begun to incorporate the use of 3D printing technology to improve the efficiency of their manufacturing processes and in turn lower the costs of production.
3D PRINTING AIDS MANUFACTURING PROCESSES
At Kirby Risk Service Center, 3D printing is being used to create fixtures or tools that supplement the facility’s methods and processes rather than produce customer-facing products. According to Michael Miller, Engineering Manager at the Service Center, they 3D print 150-200 different parts or tools that assist them in manufacturing quality products.
For example, mating connectors are often created for wire harnesses that connect to a sensor or an engine control module (Photo 1). The connector itself cannot be bought off the shelf — it is built specific to that particular sensor or control. Instead, they create a 3D printed connector so they can determine that the harness plug will fit perfectly into the actual connector. The printed connector is also fully functional electrically, allowing for harness continuity testing.
The Service Center also uses 3D printing to create poke-yoke type fixtures, or items that help a process work correctly the first time, eliminating mistakes. Miller cited the example of a T-shaped unit that goes on a formboard and must always be positioned in one direction (Photo 2). “We’ll make a fixture to hold the item in the correct orientation every time,” he says.
Assembly tool aids designed to help in the production of a specific customer product can also be 3D printed. For example, the Service Center will often assemble a control panel with connector holes that must be plugged up where wiring will not be inserted. They 3D printed a template that lays over the connectors, allowing them to position all the plugs per the template. Once positioned, the plugs still need to be pushed into place. They 3D printed a tool that comes along and, in one move, pushes all the plugs into place before removing the template. Miller says he can see the Service Center potentially using 3D printing to do more of this — if someone can conceptualize it and it is within their size and scope, they can make it.
The Service Center can use 3D printing to design prototypes of new products. During the pandemic, the Service Center worked together with Purdue University to design a prototype for an N95-style reusable respirator mask (Photo 3).
The Service Center uses two types of 3D fabrication: Stereolithography (SLA) and Fused Filament Fabrication (FFF).
Stereolithography (Photo 4) uses a liquid-based resin that hardens when a UV laser light source is placed on it. It builds a product layer by layer, producing a fully solid object. Miller says the Service Center uses this process for objects that need to have very fine features, or if the product requires very tight tolerances.
Fused Filament Fabrication (Photo 5) is a material extrusion process that uses a plastic filament, similar to a large fishing line. The filament is pushed through a heated nozzle that melts the plastic. The printer deposits this material along a predetermined path on the build plate. Once cooled and solidified, another layer is added. The printing of cross sections is repeated layer upon layer until an object is fully formed. Miller says they generally use this process for tooling or fixtures that need less precision. The process is less costly to use and maintain plus the filament used is less expensive.
Currently, the Service Center does not 3D print customer-facing products, but requests to do so are increasing. Miller says he sees this as a possibility in the future, but they would want to assure that they were following all the customer’s product validation processes. “I would never want to release anything to them as a product unless I knew they were fully testing it in their application,” says Miller.
As new materials used in 3D printing have become more pliable and easier to use, the opportunity to use them to create new items has expanded in the five years since they began using this technology. “I remember the original first SLA models that we dealt with and we had to handle them like glass, they would break that easily,” Miller says. “As new materials become available, it gives you more and more flexibility on what you make.”
The advantage 3D printing gives to the Service Center is providing another method of making custom parts or tools that are not available or can’t be purchased outright. They can produce the fixtures and tools needed to improve upon processes without having to seek an outside resource.
“We want a holistic approach to our engineering software and hardware, so we are using a singular system to do all our work. And that takes us from design all the way through to finished product.”
MAKING STEMS TOWARD 3D PRINTING
While Kirby Risk Precision Machining has been using 3D modeling software since the early 2000s, they do not do 3D printing onsite. Plans are in the works to purchase a 3D printer within the next year. A dual extrusion system is being considered that uses a plastic filament along with an inlaid carbon fiber filament. Using this material would greatly increase the strength and durability of the parts created.
As a precursor to acquiring a 3D printer, last year Precision Machining purchased a 3D laser scanning system and upgraded to Siemens NX software. Eric Kauffman, Senior Engineering Manager at Precision Machining, says this new system allows the integration of 3D modeling, with CNC programming, 3D Printing, 3D laser scanning and other computer aided engineering tasks. “It is an overarching change to our engineering system,” he says. “We want a holistic approach to our engineering software and hardware, so we are using a singular system to do all our work. And that takes us from design all the way through to finished product.”
Precision Machining uses the 3D scanning system in a variety of ways. They scan castings that are used to verify that they meet customers’ engineering needs. They scan old parts to get 3D data that may not have been available before. Precision Machining can also scan broken repair parts then reverse engineer those parts to make new ones. Once they add a 3D printer to their process, they can move to the final step of actually printing these parts. For now, Precision Machining must create the items, send them to an outside source for manufacturing, or send them to the Service Center for 3D printing.
Kauffman agrees that creating tooling used to check parts or manufacture parts is most likely how Precision Machining will use 3D printing. It will be a time saver as well, as the 3D printer can run unattended while they continue to work on machine tooled parts. He also sees other customer benefits. “The 3D printing tool is not a replacement for making parts for our customers. However, it is a way to better utilize 3D data to create quick wins for our customers, whether it be a one-off replacement part, or some physical model somebody can hold in their hands to see if it’s going to be what they want,” he says.
Kauffman envisions future opportunities for creating parts for our Supply division. For example, perhaps they could 3D print a particular bracket for hanging a light fixture if the bracket is hard to source, backordered or no longer available.
Both the Service Center and Precision Machining engineers see 3D printing as a valuable service that Kirby Risk can offer to customers. From 3D printing a replacement part or producing a tool that aids in the efficient production of the customer’s product, 3D printing definitely has a role to play in the future of Kirby Risk Manufacturing.