WAAM-based Vipra AM shows the power of application-first development

For over a decade, Italian company Caracol has developed and honed its large-scale robotic additive manufacturing technology, first with a focus on the thermoplastic and composite segment (with its Heron AM platform) and more recently with metal WAAM capabilities. Caracol’s official entry into wire arc additive manufacturing came in 2024 when it launched its Vipra AM robotic metal 3D printing platform. 

The Vipra AM solution is a highly automated turnkey system engineered for large-scale metal manufacturing. With its development driven by Caracol’s application-first ethos, the DED printer is designed to solve challenges faced by manufacturers in industries like aerospace, automotive, energy, marine, and architecture. As we’ll see in more detail, the Vipra AM solution is a force within the growing metal LFAM segment as manufacturers realize the cost, time, and efficiency benefits that AM can offer for applications ranging from near-net-shape part production to large-scale tooling.

Vipra AM, in a class of its own

Caracol’s Vipra AM, is a WAAM-based robotic 3D printing system, meaning that it builds three-dimensional structures by melting and depositing welding wire using an electric arc. Within the AM industry, WAAM technology is known for a few things, including its material versatility, its large-scale capability, and high-deposition rates. While this approach is not itself unique to the Vipra AM, Caracol has integrated a distinctive combination of software and hardware features that do make the large-scale metal AM system stand out. 

Among these distinctive features is a deposition head engineered for “extreme productivity”. Specifically, the Vipra AM integrates a print head based on Cold Metal Transfer (CMT) technology that uses a low-heat welding source to melt wire feedstock (such as aluminum and nickel alloys). This CMT approach enables high-deposition rates while minimizing thermal impact and metal distortion, a capability ideal for large-scale applications with demanding lead times.  

Another key feature of Caracol’s WAAM technology is that it is based on a nine-axis architecture. (Most competing WAAM solutions are built on eight interpolated axes for comparison.) With the addition of a ninth axis in the form of a positioning slide, the Vipra AM facilitates the handling of large, heavy parts. Without it, operators would have to rely on auxiliary lifting systems, like forklifts, to handle large-scale WAAM parts. In short, the slide eliminates the need for auxiliary equipment inside the printer cell, making loading and unloading operations safer and more streamlined.

Caracol has also integrated a number of advanced features to ensure the safety of Vipra AM operators. As the company says, WAAM printing does come with risks associated with robotic handling, elevated temperatures, optical welding, and potential fumes. It has therefore gone above and beyond with its safety infrastructure with features like a closed cell environment with an automatic door. This door is designed to ensure total optical protection during the welding process and is equipped with smart sensors that “make it an active safety element, not just a physical barrier.”

Inside the production cell, the floor is embedded with sensors that will stop the system from activating if an operator is still inside the cell. This feature mitigates risk and prevents accidents, something that is particularly important in highly regulated industries that must produce formal risk assessment documentation. 

Other critical safety features include a fume extraction system and a surveillance system (with no-shadow lighting) that ensures operators can closely monitor the print process while the door is shut. All these safety features are controlled and accessed via a centralized Human-Machine Interface (HMI) system. 

“We designed every safety layer of the Vipra AM cell to work in concert” said Giovanni Avallone, Chief Innovation Officer at Caracol. “The sensor-embedded floor triggers an immediate system halt if an operator is detected inside, the automatic door provides full optical shielding during the arc process, and the centralized HMI ties it all together into a single control interface. In high-regulation industries where formal risk assessment is mandatory, that level of integration isn’t optional.”

Advanced process monitoring

Beyond printing capacity and safety, the Vipra AM platform is also engineered for reliable, industrial production with a suite of process monitoring tools and sensors. Among these are built-in core sensors that support production and process characterization as well as a number of optional tools, which we’ll explore more below.

The core of the Vipra AM’s modular process monitoring system is a pyrometer that measures the temperature of every printed layer (or at specific points defined by the slicer). This sensor is integrated into a closed-loop automation system—developed in cooperation with Fraunhofer IAPT—that actively ensures that the optimal thermal window is being maintained throughout the printing process. In more specific terms, the thermal data from the pyrometer is fed into the automation system, which will automatically adjust wait times between layers so that the optimal print temperature is maintained. Other core sensors monitor and measure layer geometry, thermal development, and gas flow.

Vipra AM customers also have the option to add more sensors for additional capabilities and more robust process monitoring. For example, the Vipra AM platform is fitted with an inert gas shielding system that mounts on the torch in under 30 seconds. As Caracol says, this add-on “allows the material to be locally inerted during printing when needed, without having to configure a fixed inerting system. When not in use, the end effector remains more compact and agile.

Other optional process monitoring tools include a thermal welding camera that produces thermal maps of the entire work area and can be used to reconstruct temperature distribution; a profilemeter that uses 2D scanning to capture weld bead profiles for material characterization and setting new process parameters; and a 3D scanner that captures 3D snapshots of the printed part throughout the build process to establish dimensional accuracy as compared to the 3D CAD model.

“When you combine a nine-axis architecture with CMT-based deposition and closed-loop thermal control, you stop talking about individual features and start talking about a fundamentally different manufacturing capability,” Avallone commented. “Our customers are seeing lead times drop from weeks to hours, material waste cut at the source, and parts that wouldn’t be feasible any other way. That’s the shift Vipra AM brings to the table.”

Application-first 3D printing

While we could continue to talk about the various features and capabilities of Caracol’s WAAM system, it is important to remember that the technology does not exist in a vacuum. That is, Caracol’s entire metal AM development process has been driven by the needs of end users and specific application requirements. Applications like large-scale tooling components that benefit from complex geometries impossible to achieve using subtractive production methods as well as dramatically shorter lead times, or end-use parts that do away completely with costly and time-consuming tooling requirements. 

In one notable use case, Caracol’s Vipra AM technology was used to 3D print a stainless steel sampling valve body for ship repair specialist JOME Engineering. By leveraging metal AM rather than traditional casting, JOME Engineering was able to reduce the part’s lead time from 60 days to a mere 48 hours. Not just that, by circumventing the casting process for the sampling valve body, the company was able to lower its energy consumption as well as material waste thanks to the near-net-shape build.

The technology has even found a use in the demanding aerospace sector, where Italy-based Eligio Re Fraschini S.p.A. recently 3D printed a spar tool component through a collaborative pilot project. The project, which was meant to determine the viability of Vipra AM for reducing lead times and production costs for the carbon fiber lamination tool, was a success on all fronts. The 3D printed part generated far less material waste than traditional tooling methods and was faster to make thanks to Vipra AM’s high-deposition rates. The 3D printed tool was also 50% lighter than its conventionally made counterpart, which showcased how the WAAM-based technology could influence part performance in addition to production efficiency. 

In the defense sector, NP Aerospace recently employed Caracol’s metal WAAM solution in the production of a 110 kg suspension and differential carrier for the Mastiff armoured patrol vehicle. The part, printed in just 60 hours, is a critical component in the vehicle and must withstand dynamic loads, shocks, and harsh environments. By 3D printing the part, NP Aerospace was able to not only meet these performance requirements but also achieve a lead time reduction of 50%. 

These use cases are just a small sample of the capabilities of Caracol’s Vipra AM system. The technology has also been used in the production of large-scale marine propellers, pressurized tanks for carrier satellites, custom industrial machinery components, automotive suspension and differential carrier structures, and more. 

An industrial solution

Ultimately, what these use cases demonstrate is that taking a leap to a new manufacturing solution can lead to untold benefits, like greater design control, large-scale consolidated parts, dramatically accelerated lead times, greater supply chain agility, and even lower production costs. Thanks to the unique combination of high-throughput printing and industrial automation and process monitoring tools, Caracol’s Vipra AM is showing adopter industries what WAAM can do for them.