Metal casting with 3D printing

During the 2024 AMUG Conference, David Moodie of Foundry Lab and Cameron Peahl from Eaton Additive Manufacturing Center of Excellence discussed using new technology in manufacturing, particularly in die-cast metal production.

Moodie shared his experience as a startup founder, highlighting the challenges of producing diecast metal, including the need for a fast and efficient system. The conversation touched on the differences between digital casting and conventional casting, emphasising the advantages and challenges of each process.

Moodie, originally from New Zealand but now operating in California, highlighted the limitations in traditional prototyping, particularly in die-casting. He shared, “Customers wanted either a strength profile or a thermal dissipation profile. The problem was the prototype by casting; it’s too expensive.” His frustration with conventional methods led to a unique solution. Moodie explained, “I took a microwave into my backyard, and I discovered that I could produce die-cast equivalent parts without a furnace.”

A metal cast used for a car mirror. Photo by Michael Petch

This innovation evolved into a more sophisticated system. The process begins with designing moulds, which he acknowledged as a significant barrier due to a reluctance to engage in mould design. To address this, Foundry Lab developed a plugin for Fusion 360 that automates mould design from CAD files. The moulds are created using a binder jet printer, which lays down layers of ceramic powder and binder.

The heart of the system is what Moodie refers to as the “microwave system,” which heats the powder to set the binder, creating moulds that can be as thin as two millimetres. “It’s super-fast today,” Moodie stated, showcasing the efficiency of his process. The microwave system melts the metal within the moulds, ensuring an even casting. This is followed by a quench system that rapidly cools the casts.

Moodie’s approach significantly reduces the time and cost associated with metal casting. “This is casting for dummies,” he jokes, emphasising the simplicity and accessibility of his method. It’s adaptable to various metals, with temperatures ranging from 1 100 degrees Celsius to 2 000 Fahrenheit.

A metal part made using the Foundry Lab process. Photo by Michael Petch

Moodie highlighted that their technique results in parts requiring some post-processing, akin to traditional casting. He explained, “When you’re finished, you end up with a sprue on top, which you’re going to need to cut off. You treat the rest of it like a casting because that’s what it is.” The process, as he outlined, allows for the moulds to be reused multiple times, depending on the design’s geometry.

Despite the successes, Moodie was clear about the ongoing challenges and the learning curve involved. The technology has begun to attract interest from various companies for evaluation, even for applications not previously attempted, like stainless steel casting.

Cost-effective moulding process for die cast parts
Cameron Peahl from Eaton Additive Manufacturing Centre of Excellence provided insights into how their large-scale industrial power management solutions company is integrating additive manufacturing across their 300-plus global manufacturing sites. Eaton, which operates predominantly in the electrical and industrial sectors, considers castings crucial in their wide range of products.

Peahl outlined Eaton’s approach to additive manufacturing, which revolves around four pillars: Technology, advanced materials and processes, patenting, and supply chain resiliency. He stressed the importance of this integration, particularly in prototyping, stating, “We need our parts in conventional materials to stay in production, and we run into a lot of problems with additive because it is a different process.”

Highlighting the challenges of requalifying parts for additive processes in the face of supply chain issues, Peahl remarked, “We don’t have the luxury of resources to go and requalify those parts for an additive material process.” To tackle this, Eaton is exploring how additive manufacturing can expedite part production without compromising quality.

Peahl shared Eaton’s evaluation of a new technology, focusing on casting porosity, part tolerances, and microstructure. They experimented with three parts of varying complexity, including cast-in-place steel pins. He noted the distinct surface finishes and multi-shot casting, allowing multiple parts in a single run.

Eaton also utilised CT scanning to examine the castings, revealing significant differences between conventional and digital casting processes. Peahl expressed his surprise at the results, “With the digital casting process, it’s amazingly dense.” This density was especially notable in parts with cast-in-place pins, where the technology allowed for smooth metal flow and even cooling.

Throughout the experimentation, Eaton maintained low porosity in their parts, an important factor in ensuring quality and durability. Peahl’s presentation underscored Eaton’s commitment to leveraging additive manufacturing to enhance efficiency, quality, and resilience in their supply chain.

The article first appeared in 3D Printing and can be read at https://3dprintingindustry.com/news/metal-casting-with-3d-printing-david-moodie-foundry-lab-cameron-peahl-eaton-additive-manufacturing-center-of-excellence-230128/