When the first man-made skating rink opened in London in the summer of 1844, it was not made of ice. No technology at the time could keep the necessary quantity of water frozen.

Instead, patrons skated on “Not-Ice”, a slippery composite of salt, copper sulfate and lard. The pig fat made the surface slick enough to glide across; it also made the building unbearably smelly. According to Smithsonian magazine, the stench was so foul that it forced the rink out of business.

Almost two centuries later, the ingredients to make a skating rink are a bit different.

Modern NHL rinks are frozen onto a slab of refrigerated concrete. Technicians flood water onto the concrete in layers. A white layer is frozen, then rink markings are painted on top. Finally, the whole thing is sealed under several layers of clear ice. When the process is done, the ice is about three-fourths of an inch thick.

Making sure that ice is exactly the right temperature and consistency is crucial. If the snow on top is too dense, the puck won’t slide smoothly. If the ice below is too warm, the paint underneath will bleed. If the air is too humid, the rink will fog.

Patrick Schuler walks that delicate line in the hottest region of America.

In 2001, Schuler started out by driving the ice resurfacing machine at the Scottsdale Ice Den, where the Arizona Coyotes practice. He is now in his fourth year as ice technician at the Coyotes' Gila River Arena. Everything regarding ice creation and maintenance is his responsibility.

“I just basically wanted to come in and watch hockey,” Schuler said. “It just kind of snowballed from there.”

According to USA Today, the Phoenix area is the hottest in the country, with 169 days over 90 degrees Fahrenheit every year. But the biggest challenge to creating an ice rink in Glendale isn’t the heat; it’s the water quality. Before it gets flooded into the rink, the mineral-abundant water at Gila River Arena is heavily filtered. Schuler says its quality can’t compare to cities with access to naturally pure water like Montreal, Edmonton, Winnipeg and Saint Paul, which are regularly ranked as having the best ice in the NHL.

"Some of those guys up in the northern places, they don’t even have to filter it at all, they can just use straight city water," Schuler said. "... If I just used straight city water, all the lines and logos would just fade away because of all the particulates in the water there just kind of clouds everything up.”

The heat presents its own two-fold challenge. For one, although the building in Glendale is relatively good at retaining air conditioning, the building temperature inevitably climbs when the outside doors open to the sweltering heat. For another, spectators often come into the arena dressed for summer and unprepared for cold.

"They want us to keep between 60 and 64 degrees, per the league mandate," Schuler said. "Sometimes we’ll try to go a little bit colder to stay ahead of the heat and stuff like that, but they want a balance between appeasing the fans not freezing their butts off and also keeping good quality ice."

Another issue with hockey in the desert is the arid atmosphere. Schuler has tricks to relax the ice during particularly dry weeks, including warming the arena at night so it doesn’t dry out. But because most days are bone-dry in Arizona, he isn’t equipped with dehumidifiers, making the few rainy days of the hockey season tough.

"The snow on top tends to get heavier," Schuler said. "It’s saturated with moisture from all the water in the air, so when the snow accumulates it gets a little heavier, and players can tell it affects the puck more."

Players are always acutely aware of how the ice is affecting their game, from puck movement to the bite of their skate blades when they push off. Poor ice can be dangerous: the career of the Detroit Red Wings' Anthony Mantha was derailed when his skate caught in a rut during their prospect camp in 2014, leaving him vulnerable for a hit that broke his tibia. Beyond the danger, ice often gets blamed by players for bad bounces or flubbed passes. NHL players told ESPN in 2017 that they blamed ice quality across the league for a decrease in quality of play.

With players' strict expectations and the challenges the rink maintenance crew faces in Glendale, as well as preconceived beliefs about how Arizona heat will affect the ice, it's no surprise that Gila River Arena has taken some hits about its ice quality over the years. In a 2018 NHLPA poll, players ranked Gila River as having the second-worst ice in the NHL, behind only the Florida Panthers' BB&T Center. In 2017, former Coyotes goaltender Mike Smith blamed the ice in Glendale for a bad bounce off the boards that put the puck in a dangerous area for a goal against.

"It's like slush out there," Smith told The Republic in 2017. "That puck was going to come out of the trapezoid, and then it just ended up stopping dead right on the line."

Player feedback can be crucial to improving the ice. Brooks Orpik told ESPN in 2017 that the rink in Pittsburgh was one of the best in the league because ice technicians had received constant reports from Penguins captain Sidney Crosby.

"Sid would go every day and constructively sit down with the guys who ran the rink and tell them exactly what he felt was wrong with it," Orpik told ESPN. "It was good dialogue between them, and the ice started getting better and better."

Although player input is important in evaluating ice quality, comments often come in heated post-game moments. Knowing that, Schuler relies on a variety of impartial trackers. He monitors the temperature and humidity levels throughout the building. He watches a sensor in the concrete slab and an infrared camera on the ice surface. Postgame, he receives firsthand ice reports from referees and the head equipment manager.

After every event or Coyotes game, Schuler spends hours repairing the ice. The rink is installed just once at the beginning of the season; the one draft picks skated on during the June prospect camp is at its core the same ice that was put in last September.

Over those months, the ice weathers daily damages. Shovel crews and resurfacing machines scrape away the top few layers every Coyotes game. For non-hockey events at the arena, protective flooring is installed, but spilled drinks can seep through gaps and drip down to the paint below.

Beyond everyday wear and tear, occasional crises arise. Schuler’s biggest challenge came in 2017, the weekend before a Coyotes preseason game. He found out about an equipment malfunction at the plant that cools the arena's ice when water began welling up from flooring laid out for a concert. Schuler and his crew peeled back the floor to survey the damage and found the ice irreparably softened.

“We had goal lines bleeding into the crease, crease bleeding into goal lines," Schuler said. "The paint had gotten so warm that it started to bleed underneath the ice."

With one day until puck drop, there wasn't enough time to repair the ice, and the Coyotes were forced to cancel the game.

“Since then we’ve made additional safeguards to make sure that can’t happen again to us,” Schuler said.

Gila River Arena is not the only NHL arena to face setbacks to making and freezing ice. In 2017, an ice compressor at the Carolina Hurricanes' PNC Arena malfunctioned, softening the ice so badly that a regular-season game had to be postponed. Earlier that season, news had broken that the New York Islanders' Barclays Center was not up to NHL regulations; the concrete slab under the ice was chilled through PVC pipes, which couldn't lower the temperature as effectively as standard steel pipes.

As ice across the league comes under continual scrutiny, maintenance of NHL rinks has evolved. When Schuler first started, in-game snow removal involved shoveling at the goalmouth and in front of the benches; now, the crew clears the entire sheet. Pregame activities have been restricted, and in 2013, the NHL extended intermissions from 17 to 18 minutes so there would be more time for ice repair between periods.

Skating rinks have come a long way from lard-infused Not-Ice. Still, with so many different factors that go into making the rink NHL-ready, it’s no surprise that Schuler’s ice challenges him every day.

“It’s definitely a living, breathing thing that you’ve got to watch all the time,” Schuler said. “It’s always changing on you, so it’s tough to keep those guys happy. But it’s what I signed up for.”

Reach reporter Julia Stumbaugh at Julia.Stumbaugh@arizonarepublic.com. Follow her on Twitter @julia_stumbaugh.

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