Curling is a sport played on pebbly ice

In curling ice venues, there are signs posted: “No Zambonis allowed.” How can that be?

Everyone has seen on television how the bulky Zambonis chug around an oval ice rink, smoothing the surface before figure skaters perform their routines. Furthermore, Zambonis are the official ice resurfacing machines of the NHL (National Hockey League).

 

Curling ice is different; it’s pebbly, on purpose, said Alan Baldwin, a correspondent with Reuters, the London-based news service. 

Baldwin told his readers that one of the world’s leading curling ice technicians, Mark Callan of Glasgow, Scotland, “recoils at the idea of a Zamboni ever being driven out onto one of his curling sheets.”

Treating curling ice with a Zamboni “would be like trying to shave with a Flymo,” Callan said. (Flymos are hovering lawn mowers, manufactured by the Husqvarna Group, based in Stockholm, Sweden.)

 

Sportswriter Marissa Payne interviewed Hans Wuthrich of Gimli, Manitoba, Canada, another high-profile curling ice maker, who said a Zamboni “would be a curling rink’s worst nightmare.” 

Hannah Osborn of the Smithsonian in Washington, D.C., said that the curling “ice men sprinkle two layers of water droplets on top of the ice that freeze to form two heights of bumps. The pebbles, just like the concavity in the bottom of the curling stone, minimize the surface area of the stone and therefore minimize the friction.”

 

“If the ice were flat, the friction on the stone would be too high and the 44-pound stone would not travel half as far,” Osborn said. “Pebbling was designed to mimic the natural snow and pebbles that were on the ice when curling was played outside.” 

The pebbling also determines how much a stone can curl (or curve). 

Both Callan and Wuthrich are working the ice at the 2022 Winter Olympic Games in Beijing, China. They were also involved as consultants, in the conversion of the National Aquatic Center there from the “Water Cube,” as it was known during the 2008 Summer Olympic Games, into the “Ice Cube” for the upcoming curling competition, Feb. 2-20.

Hans Wuthrich 

The Chinese were trying to save money, Wuthrich said, “by turning the existing summer venue to a winter one.” Laying flooring over the swimming pool and converting the place into an ice arena has presented numerous challenges. “But we’ll be ready,” he added. 

Asians are fairly new to the sport of curling, but the Chinese and South Korean teams are getting pretty good, Wuthrich said. He can’t wait for the “sweeping” to begin. 

He’s referring to action by the players with the curling brooms who briskly brush the ice in front of the sliding stone to “guide” it into position to score points, serve as blockers or bust up the opponent’s advantage. 

“The positioning of the sweepers is also strategic. The sweeper closer to the stone has more influence, because the stone has more time to travel over the water film before it re-freezes,” Osborn said. 

If a player accidentally touches a moving stone with a broom or body part, this is an infraction, and the stone is removed from play or “burned.”