“We came up with a method of using the ULTEM 1010 to print the master pattern tooling, which enabled us to get our tools much quicker,” says Miller. “Since the geometry internals were quite tight, we weren’t going to be able to use the traditional bagging method. One of the other benefits of the FDM technology is that they have some materials that are soluble in a detergent solution. We can laminate the part around a soluble core, and once the part is cured in a solid we can dissolve the core out from the inside.”
With the 3-D technology, Penske met the deadline while saving money. Master patterns built using traditional tooling would have cost $8,500 and taken three to four weeks; with the FDM printer, it cost just $870 and took less than a week.
Penske also uses a selective laser sintering (SLS) printer to produce race car components such as carbon monoxide filters for drivers’ helmets, brackets and wiring housings for vehicle interiors, and exterior parts like brake ducts. They are printed with a low-density carbon fiber-reinforced nylon that provides strength and, when needed, temperature resistance.
To further expand its additive technologies, Penske added a PolyJet printer through its Stratasys partnership. “It’s like a traditional inkjet printer, but instead of printing ink, it’s printing a curable liquid photo polymer that is cured by UV light,” explains Miller. Penske designers will use this machine to produce part mockups, freeing up the SLA machines for steady wind tunnel model part demands.
The PolyJet will also offer unique flexibility in mockup parts design. An inkjet printer has several color cartridges that can combine to create a variety of hues; similarly, the PolyJet cartridges can hold several different polymer systems that can be combined in various ratios for different material properties.
Miller says Penske hopes to see more large-format 3-D printers that can work with continuous fiber reinforcements and materials with higher temperatures in the future and closely monitors that space in the additive industry. “There’s the potential that you could get higher strength and more structurally optimized components with it,” he adds.
Daniele Cevola and Francesco Belvisi are co-founders of Livrea Yacht, a yacht design and manufacturing company based in Palermo, Italy. They introduced their first yacht model with 3-D printed parts – the Livrea 26, Born by the Wind – at the Miami Boat Show in 2014. Most of that boat was built using carbon fiber molds and conventional composite manufacturing techniques, but some small sections were 3-D printed. “Our partner, the CRP Group, used only sintering 3-D printing technology, so there were limitations on the size of the parts we could build,” Cevola explains.