Mercury may have had wings on his feet, but the best mortal runners can do is to have carbon fiber plates in their shoes.
Theoretically, the carbon fiber plate adds stiffness to the sole of the shoe, preventing the flexing and energy loss that occurs in a conventional sole. The less energy lost should result in a better time over the course of a marathon.
The marathon sensation Eliud Kipchoge used a prototype of the Nike Vaporfly 4% to become the first runner to break the two-hour marathon mark with a time of 1:59:40.
Now comes a molding company, ARRIS Composites, that claims it also has a carbon fiber plate to consider.
You Say You Want a Revolution?
In ancient times, runners raced barefoot. During the Greek Empire, runners wore sandals. Spikes were added to gain traction in the mid-1800s. Adidas introduced the modern running shoe with the characteristic three stripes in 1949. Nike got into the shoe business with its revolutionary waffle sole (literally prototyped with a waffle iron) in 1971, a design that enabled runners to get traction without spikes on practically any surface. The march of materials and technology that benefitted many sports—carbon fiber in tennis rackets, bikes and hockey sticks; hydrodynamic swimsuits; titanium in golf clubs; and so on—was to leave the lowly running shoe practically untouched. That is, until 46 years later when Nike introduced the Vaporfly 4% with a carbon fiber plate in the shoe’s sole.[i]
Every revolution has its detractors, and the carbon fiber plate is no exception. Some say it provides an unfair advantage, with a technology that is not available to all. A fair point, as the Vaporfly starts at $250 and the manufacturer’s most expensive model, the Nike Air Zoom Alphafly Next% 2, sells for $285.
About ARRIS Composites
One composite molding company down the West Coast from Nike in Berkeley, Calif. seems to have advanced the state of the art in carbon fiber plates for running shoes using "additive manufacturing," a first-of-its-kind manufacturing and materials.
ARRIS’ carbon fiber plates are also distinctive on the inside. The carbon fibers are laid along the pattern of the molded design, resulting in long strands of continuous fibers. Continuous fibers, unlike the chopped fibers often used in most 3D printing processes, and produce parts with maximum strength.
Until ARRIS, all carbon fiber plates for running shoes have been solid -- no cutouts. “If someone wanted to create an open structure carbon plate like the ARRIS design, the fiber alignment simply will not compare to the performance made possible with the ARRIS continuous fiber technology,” says CEO Riley Reese, who in addition to being an avid runner, has a master’s degree in material science from UC Berkeley.
ARRIS has a patented process to make rapid molds and parts in which continuous carbon fiber is laid along the direction of structural necessity, which in theory ensures that the part is as light and strong as possible.
Let’s Not Forget Sustainability
“Composites are messy,” says Reese. He claims an improvement with rapid-molded composite parts in terms of sustainability over conventional methods.
“ARRIS tech uses a near-zero waste and lower-energy process with materials that are recyclable thermoplastics (versus thermosets which are not), and ~50% of our material is bio-based,” according to ARRIS’ website.
Run a Mile in Those Shoes
Reese’s interest in the sport runs deep. He has completed so many marathons that he has lost count. “Four to six road marathons and 25 to 30 marathons—or longer—on the trail.” It is no wonder, with the varied parts and various industries that ARRIS serves, it is the lowly shoe that has Reese most excited. In a manufacturing Happy Hour interview, Reese discussed the successful use of his company’s carbon fiber plate in the New York Marathon, although admitted it was frustrating to watch from the sidelines.
[i] Reebok had a carbon fiber plate in a running shoe before Nike, but its plate was too stiff and the shoe did not catch on.