PEAK is a leading sportswear brand, established in China in 1989. In 2015, PEAK’s revenue surpassed 3 billion RMB (about $US 430 million). Two years later, PEAK became a pioneer in manufacturing shoes using 3D printing. Now PEAK has fully embraced 3D printing technology in its footwear manufacturing process. While other companies have focused exclusively on the midsole and insole, PEAK 3D prints the entire shoe, including the upper. Thanks to this innovation, PEAK’s release of 3D printed sports shoes has intensified and the improvements that 3D printing has brought to PEAK products are evident.

In November 2021, PEAK’s lightweight basketball shoe series, the TaiChi, released a 3D printed model. Its upper was printed using Raise3D material extrusion systems and a thermal-sensitive material that changes color according to variations in temperature. In December 2021, PEAK released the first version of its new 3D printed sneaker series, Future Fusion 3.0xSeapool, with a limited run of 199 pairs. Today, PEAK is a giant with more than 5,000 retail stores in China.

Future Fusion 3.0 rebirth

“We purchased our first SLA printer for industrial design in 2013,” says Huang, Zheng, Director of Technology and Innovation of PEAK Sport, “with the goal of digitizing our entire design process, from motion design to development. We then tried the FFF process relatively early in our overall technology research, at a time when only PLA and ABS were commonly available. Then in 2018, with TPU filament, we first tried to directly 3D print the entire shoe upper, and other related parts, using FFF printers.”

That was a game-changer. PEAK rebuilt its manufacturing process from the bottom up and around 3D printing. For example, the Future Fusion 3.0xSeapool’s upper was fabricated using Raise3D FFF (Fused Filament Fabrication) technology. This shoe upper is directly formed by successively depositing multiple printed layers. For each layer, the printer uses a colored material as a thread, with 0.4-0.8 mm in diameter, following a crossed path that forms a pre-determined grid pattern. Therefore, the printer can draw each layer with a different pattern and color. As the FFF printer builds layers upon layers, it forms a composite fabric that is permeable, with a unique, creative appearance, permeability, and unlimited combinations.

“After the introduction of 3D printing, our production is mainly divided into two parts,” explains Zhao, Fujian, Production Manager at PEAK Sport. “One production line is for the finished shoe and another one is for loose components. After introducing 3D printing to replace all of our leather materials, we could do away with punching of the mesh and the high frequency (HF) welding process was completely eliminated. This would normally take more than 50% of our overall production time with high equipment costs for cutting and electric carving, stamping and sewing. Overall we reduced the production time by one-third with much less human labor involved.”

Based on this method of fabrication, PEAK rethought its sneaker production process, resulting in a procedure based on 3D printing that is shorter and more flexible than the original manufacturing process. The most significant improvement is the shoe upper fabrication phase. Through the integrated FFF printing solution provided by Raise3D, PEAK replaced the eight original flyknit procedures with three new procedures. Due to the high level of digitalization of the FFF printing process, these new procedures are more efficient when it comes to variable quantities and product demand.

In addition, compared with the flyknit process, initiating a new printing line does not need a huge amount of labor to program a sophisticated weaving path. Instead, 3D printing software automatically generates printing paths and a corresponding machine command code. A 3D printer is much easier to calibrate for material loading and unloading, without the need for tool changing and can deliver shoe uppers with any pattern or combination following a pre-determined printing path.

These features also bring considerable advantages in terms of prototyping iterations. The use of 3D printing allows for the rapid prototyping of functional shoe uppers and midsoles that can be directly assembled and worn. This process enables PEAK to carry out more design iterations that are also quicker.

At your feet in 10 days

The batch production of 199 pairs of Future Fusion3.0xSeapool took just ten days. Once the CAD design was defined, the 3D printing manufacturing phase started immediately and seamlessly. First, the sneaker uppers and midsoles were 3D printed simultaneously over the course of four days, by two distinct 3D printing technologies. It took two more days to gather all the 3D printed components and another three days to queue and go through the assembly process.

As an example, while the midsoles were printed via SLS, the uppers were printed using Raise3D’s specialized footwear printing solution, which delivers a pair of sneaker uppers in about three hours. There is no need to adjust the printing procedure since the various shoe sizes of the uppers are included in the task queue. Multiple printers working synchronously require very little human labor.

Before PEAK fine-tuned the production process for the Fusion3.0 models, the company made headlines with the first FF1.0 model, released in 2019. “At that time, it actually set a benchmark for the industry, with a powder-sintered midsole and the FFF-printed shoe upper,” says Jijie Lin, 3D Printing Specialist at PEAK, in charge of production. “We were invited exhibit this product in the USA as guest speakers among international brands. But – Lin adds – there is still a very long way to go. After all, it’s an emerging technology […] As the materials and processes continue to mature, I think more brands will step into this area to embrace it. There’s certainly lots of room for improvement.”

One of the elements that have emerged from PEAK’s experience is that there are also several immediate and evident benefits. Using 3D printing results in a much lower production cost per unit, making it ideal for small-batch production. With traditional processes, mass production of shoe uppers is carried out with knitting and cutting. The cost structure of this type of process is not suitable for small batches. It requires an extremely high investment of around 25,000 USD to purchase a single set of knitting and cutting equipment.

A high quantity of material is required for each processing round to break even with the depreciation of the machine and tool cost. Therefore, fabricating 199 pairs of shoe uppers with this type of equipment would result in heavy losses or unreasonably high prices. However, Raise3D’s printing technology is affordable and capable of producing any needed quantity of uppers, without hidden costs or high levels of depreciation. Furthermore, with footwear 3D printing technology continuing to evolve in the future, cost-efficiency will likely improve even further.

Sneaking up on the future

The market witnessed PEAK’s efforts and subsequent success in implementing 3D printing. Now PEAK further expanded the 3D printing family with the Fusion Series, Future E and Future Alpha models. The Future Fusion series continues to evolve, with the latest Future Fusion 3.0 model. Moreover, PEAK brought 3D printing to the TaiChi series, its star product.

In the company’s history of implementing 3D printing, PEAK employed different printing technologies and new business strategies. One of the next evolutions involves the use of increasingly flexible TPU (Thermoplastic Polyurethane) materials. This way the upper can be printed as a flat part and later be bent and assembled, eliminating the need for a support structure. Such integration contributes to PEAK’s deep research into 3D printing mechanisms and manufacturing applications.

The Future Fusion 3.0 series is evolving at a product and manufacturing level by making the most of 3D printing. Compared with previous versions it features design breakthroughs such as detachable shoe upper accessories but also improvements in manufacturing cost-efficiency.

The footwear industry’s transformation toward embracing the 3D printing process needs support from technology suppliers capable of providing proven solutions. To implement flexible manufacturing, manufacturers must integrate digitalization, materials, and machinery. Once there are manufacturers eager and focused on 3D printing implementation, like PEAK, will find their strongest ally in versatile AM technologies such as those developed by Raise3D.