From Months to Days: Radio Flyer Accelerates Cargo eBike Prototyping with Formlabs Fuse X1

Designers can only iterate as fast as their tools allow. A few years ago, creating a single cargo e‑bike prototype at Radio Flyer took two months. The launch of the Form 4L slashed that to two weeks. Today, the Formlabs Fuse X1—an industrial‑grade selective laser sintering (SLS) printer—brings full‑size prototypes into the lab in just two days.

“With Fuse X1, we can print an entire Flyer Loop cargo e‑bike overnight and assemble it the next day. We moved from two months to two weeks to a couple of days,” says Agostino LoBello, Product Development Engineer.

Radio Flyer has delivered wagons, scooters, strollers, go‑karts and bicycles for over a century. Since its inception, the company has embraced cutting‑edge technology to accelerate product development. LoBello has championed tools like the Fuse 1+ 30W, Form 4L and now Fuse X1, enabling rapid iteration and on‑site road‑show prototypes.

“Fuse X1 raises the bar for what we can deliver at road‑shows—more frequent iterations, nine times less labor. That’s a compelling value proposition,” he explains.

The Fuse X1 sits on a 12.2‑sq‑ft footprint with a 330 × 330 × 565 mm build volume, making it ideal for large parts in a compact space.

“Our frames and accessories are custom‑designed to serve families. In‑house printing frees us from off‑the‑shelf constraints,” LoBello says.

Radio Flyer’s in‑house design process covers everything from the frame to baskets and sunshades. When the company first ventured into e‑bikes, a prototype frame required two months: a metal frame was built, then clad with multiple small prints. The Form 4L’s larger build volume and robust materials let engineers skip the metal step, breaking the CAD model into 19 builds. That still required a week of printing followed by days of assembly.

Prior to Fuse X1, a bike frame prototype was printed in 19 separate builds and glued together.

With Fuse X1, the Flyer Loop e‑bike frame is printed in just two builds and assembled in three days total.

The final Flyer Loop cargo e‑bike.

Outsourcing large parts would have taken weeks, and LoBello prefers full control to guarantee prototype quality. While other large‑format printers were considered, their cost couldn't be justified given Radio Flyer’s print volume—until Fuse X1 changed that equation.

“The paradigm shifted with Fuse X1. Its value now aligns with the number of parts we print, making it a perfect fit for our prototyping workflow,” he notes.

Fuse X1 (left) has a compact footprint; Fuse Sift X1 (right) is a large‑format powder recovery station that cleans parts and reclaims powder.

At Radio Flyer, working prototypes are essential for ergonomics testing and observing how families interact with the product. Road‑show prototypes must look finished to secure retail buy‑in. The more realistic the prototype, the better the feedback.

The 330 × 330 × 565 mm build volume allows LoBello to print an entire cargo bike frame in two builds, or an entire scooter or tricycle in one build. In‑house printing eliminates the weeks required for outsourcing and speeds up time to market.

“With Fuse X1, I can iterate three times as often with nine times less labor—an attractive proposition,” he reiterates.

Fuse X1 builds are prepared in PreForm. LoBello says, “Fuse X1 is especially easy—no need to split designs. I can drop the CAD file into PreForm, and it prints reliably every time.”

“When something prints on Fuse X1, it comes off the machine ready to assemble—no filing, sanding, or post‑processing needed. That’s a huge win.”

Agostino LoBello explains that the Flyer Loop frame can be printed in two Fuse X1 builds, with parts that are dimensionally accurate and snap together effortlessly. This lets him focus on design intent rather than print constraints.

Team members are thrilled with the speed from render to prototype, which allows the soft‑goods department to design accessories—kid carriers, sunshades—in parallel. The design team now prints full‑scale preschool products, such as scooters and trikes, overnight and reviews them the next day against existing models.

LoBello notes that parts printed on Fuse X1 fit together without adjustment, saving valuable time.

Rapid in‑house prototyping enables more iterations, allowing the team to test and respond to feedback quickly.

“There’s a lot of ongoing innovation in the cargo bike space. Fuse X1 lets us develop faster and stay on the cutting edge, bringing new ideas to market efficiently,” says LoBello.

Three weeks after receiving Fuse X1, Radio Flyer’s engineering team had already printed full‑size prototypes of multiple products while still running builds on Form 4L and Fuse 1+ 30W. For the team, Fuse X1 is the newest tool that expands print size while trimming timelines and labor.

From Form 4L to Fuse 1+ 30W to Fuse X1, Formlabs 3D printers are accelerating Radio Flyer’s product development and delivering innovative, play‑focused products to the market.

Explore Fuse X1 to learn more about industrial SLS 3D printing, or contact sales to request a quote.