Spanish aerospace engineering and production specialist, Indaero, recently invested in a Stratasys Fortus 450mc Production 3D Printer to complement its existing manufacturing services. The company manufactures aircraft panels for customers such as Airbus and its suppliers. Specifically, the Stratasys 3D printer acquisition has enabled Indaero to offer lightweight, complex tooling that it was previously unable to produce with traditional manufacturing methods.
The production tools, of which there are several, have contributed to significant advances in Indaero’s production process. Many of Indaero’s products require in-house tools for assembly. One of those products (for Airbus supplier Aernnova) is the NH90 helicopter.
Before acquiring additive capabilities, the company was limited to producing flat shapes with traditional methods, which affected the performance of the final tool during production. In the past, an aluminum tool weighing 12 kg was required to affix a slide box onto the interior panel of a NH90 helicopter wing. The heavy tool was manufactured using traditional subtractive methods and required two operators to hold it against the panel while marking the drill holes.
With the complex geometries achievable with 3D printing, the Indaero team redesigned and printed the tool with a curvature perfectly fitting the panel structure. As a result, the new tool is more effective and 9 kg lighter than its predecessor.
“Integrating FDM (fused deposition modeling) 3D printing within production tooling for this project is delivering several clear benefits,” said Darío González Fernández, CEO of Indaero. “First, from a resource perspective there’s now no need for two operators as the tool fits against the panel independently—leaving one operator to position the slide box with both free hands. Second, we can produce a lightweight and robust tool 66% faster than with CNC machining. As a result, this part of the project is being completed ahead of time, leading to a reduction in manufacturing cost of over 50%.”
Unique among other industries, manufacturing in aerospace requires high volumes of tools. “To traditionally manufacture production tools, injection molding or CNC (computer numerical control) machining would be used, but this would be very time-consuming and costly," said González. "With our new 3D Printer, we can service low-volume production quickly and cost-effectively, producing many different tools on demand to accelerate the manufacturing process and ensure we meet delivery deadlines.”
The importance of the ULTEM 9085 material cannot be understated either, he said. “It has become an integral part of our production process, as it is certified for aerospace and well known by Airbus for a number of aircraft applications. With its unique combination of high strength-to-weight ratio and FST (flame, smoke, and toxicity) certification, we can 3D print robust, lightweight tools and respond to short run production of flying parts if required.”
3D printed tooling leads to increased business
“The 3D printer has been a game-changer for us,” said González. “The ability to 3D print curved production tools in robust materials made us realize the importance of having tools that perfectly fit the panels. Not only does it make the work of our operators much easier, it frees up resources and increases our overall productivity. This improvement was immediately recognized by providers such as Aernnova, who previously worked with our competitors and whose business we have subsequently secured.”
Since acquiring the printer, Indaero has covered every area of it manufacturing environment with 3D printing, from final parts, functional prototypes, mechanism components for some other products (engine ground covers) and, of course, tooling.
Sometimes, the tools are sacrificial, but the majority of Indaero’s tooling are reusable components. Depending on the application, their durability isn’t comparable to traditionally manufactured tools. For example, a carbon fiber permanent mold printed with ULTEM 1010 has demonstrated to last with a reliable life of 100 uses. However, parts that incorporate traditionally manufactured bushings (heat or pressure inserted) or threaded inserts can last an extremely long time if correctly designed. This is the case of some of the tools designed for the NH90.
Rapid and cost-effective manufacture of complex tools give Indaero an edge with low volume production jobs, but for larger projects, economics comes into play.
For 5000 or more identical units of a given product, 3D printing may not be profitable when compared to injection molding. Manufacturing parts that could be easily approached with CNC does sometimes compete in prices with 3D printing, depending on the manufacturing strategy and the desired geometry. And simply, there are applications (fatigue, etc.) that are not approachable using 3D printing with current means.
Sometimes Indaero combines CNC and 3D printing to optimize costs and lead times, using the best of each technology. Currently the company estimates that 20% of production involves 3D printing.
As far as aerospace production, Indaero has designed and manufactured drilling, bending, and assembly tools for the Airbus A350 XWB and A330 Multi Role Tanker Transport (MRTT) programs; as well as verification tools for the A400M program, some of which were completely 3D printed, and retain comprehensive functionality.
The company has begun research work involving a new Stratasys material called ST-130, involving 3D-printed carbon fiber curing soluble molds, which allowing the creation of hollow bodies such as air ducts.