Jobst Gellert is one of the most prolific inventors in Canadian history, with a whopping 825 patents worldwide. In 1963, Gellert and his wife, Waltraud, founded Mold-Masters Ltd., in Toronto — the first company to exclusively manufacture hot runners.
Today, as Gellert goes into the Plastics Hall of Fame, the global hot-runner industry is a $1.5 billion business. Mold-Masters employs more than 1,600 at seven manufacturing plants and service centers at more than 70 countries.
Gellert, 81, is retired from the company. He and Waltraud remain shareholders and she serves on the board of directors.
Gellert wanted to become an engineer as a youngster in Germany. But World War II disrupted his early education and family life. So he served an apprenticeship as a bicycle mechanic and later trained as a mold maker. At night he studied drafting and math.
In 1956, he passed the German examination to become a master mold maker — the words were flipped to create the Mold-Masters name later.
Gellert immigrated to Canada in 1958 and worked at several companies, including Husky Injection Molding Systems Ltd., before starting Mold-Masters in 1963.
Hans Guenther retired from Mold-Masters in 2007. “We came from the same town in Germany, so when I tried to come to Canada, I contacted him and he sponsored me,” said Guenther, a mold maker who immigrated in 1970 and went to work for Gellert the following year. Gellert already had a few presses running.
Longtime Mold-Masters employees say Gellert was a passionate, sometimes impatient man driven by new ideas. It could be tough to keep up.
“In the middle of the night he would wake up with ideas,” said Patrick Bennett, president of Mold-Masters Europe. “He couldn't wait to get to work so he could share his ideas with the team. He would like to think that, after lunch, he could have the idea in steel. He was so excited about the idea of what it could be.”
Hans Hagelstein, president of global engineering, chuckled as he recalled that Waltraud sometimes would call ahead while her husband was on his way to work.
“He had no sleep last night, so be patient with him,” she told them.
In 1998, Gellert built a separate research and development center and staffed it with 20 people and its own tool shop and injection molding machines.
The idea behind Prodevco (the name deriving from “product development company”), was to create a dedicated center for industrial creation, away from production, said Denis Babin, product development manager.
“Mr. and Mrs. Gellert always put back into the company for research and development. It was the future,” Babin said.
“He was the thinking man,” said Guenther. Prodevco was an oasis. “He could do what he wanted and nobody could interfere with him.”
Back in the early 1960s, the idea of hot runners to keep the plastic runner liquid and ready for the next shot, was brand new. They could dramatically reduce cycle time and reduce scrap by eliminating the need to handle the runner. But early versions had problems isolating the hot melt from the cold plates in the mold, because they used basic cartridge heaters right inside the runner.
Gellert filed his fundamental patent in 1965: cast-in heater elements positioned outside the melt channel. He used beryllium copper nozzle components. The heater elements were fused to the body of the nozzle. The U.S. patent was granted in 1968.
“We built on and refined it with different materials. From there we went onto other products,” Guenther said.
The result was enhanced heat transfer, uniform heat along the entire hot runner. Guenther said a breakthrough was using nickel braising of the heating element into the body of the hot runner.
Gellert was not finished, of course. In addition to that first patent, he invented new technology for melt distribution manifolds, hot-runner nozzles, actuation methods and mold designs.
Soon, hot-runner molding became a global trend.
“Every hot-runner company in the world uses the principle that Jobst developed, invented, patented and commercialized,” Bennett said.
The innovations helped open up high-cavitation molding, coinjection and multicomponent molding.
Mold-Masters gained some big customers, including Rubbermaid Inc. and Kodak Co.
The Gellerts moved their business to Georgetown, Ontario, in 1973, where the head office remains today. Mold-Masters opened a facility in Japan in 1984, established manufacturing in Germany in 1989 and opened a plant in China in 2005 and one in India in 2010.
Guenther said Mold-Masters came up with a constant stream of new products. Everybody would come by the company's booth at trade shows — even competitors.
Guenther said Gellert could be difficult, but is a brilliant inventor.
“He was a guy who had no patience but a very technical mind. When the new development was three-quarters finished, he was not interested any more, he already had new ideas in his mind. He was relentless and, well, he was a genius as far as I'm concerned. A guy not easy to work for but with a huge heart,” Guenther said.
“He was impulsive and impatient,” Bennett said. “He was a mad scientist inventor. At times he would get frustrated because we couldn't keep up. He could come up with inventions and ideas faster than we could execute.”
Gellert has strong feelings on worker training, intellectual property and the value of manufacturing. He delivered a paper at the 1979 CanPlast conference titled “Can Canada Compete Internationally?” The answer, he said, is yes — but only by strengthening its patent protection and improving its industrial education. He said Canada's economy relied too much on extracting its rich natural resources like nickel, uranium, and forest products.
“Real wealth does not come out of the ground, but from the strength, skills, talents, venture-seeking and risk-taking [of] citizens,” he wrote.
He spelled out the need for education reform and the importance of real-world training in a 1991 letter to a political leader.
“What Mold-Masters and every other company needs is good, competent, competitive-minded young people with which we can do better in the marketplace. Since we rarely get them from school, we cultivate these people ourselves.”
Those opinions still resonate today, two decades later.
Gellert proposed a program in which industrial “masters,” qualified by the trade associations, would share their knowledge with young people — and give those experts tax breaks as an incentive. That would become self-perpetuating, he wrote.
“Every competent man has a chance to create his own living memorial, who will go on and become masters if they are patient and believe to give like they have been given, become champions of training young people themselves.”
Veteran employees said that Jobst and Waltraud make a great team.
“She was in charge of finance and the commercial side of the company. She's the smartest businesswoman I ever met,” Bennett said. “While Jobst was so passionate about the technology, the company would never have become as large as it did. She was the yin to his yang.”
Others agreed. “They were a team. Take Waltraud out of it and he wouldn't have succeeded. He was the creative entrepreneur, but she knew the business,” Babin said.
Gellert insisted on the most modern equipment. Waltraud controlled the purse strings.
“When he wanted a new machine, he was miserable until he got it,” Guenther said. “He didn't care about money. Without her, the company would have never gone where it did today. They were both driven to succeed.”
Bennett said Waltraud made sure her husband's inventions got patented. Of Gellert's 825 patents, 199 have been granted in the U.S.
A debilitating stroke forced Gellert to retire as CEO in 1999. But he continues to provide creative inspiration to Mold-Masters.
In 2007, the Canadian Plastics Industry Association gave him a Lifetime Achievement Award.
Gellert was nominated for the Plastics Hall of Fame by Bruce Catoen, Mold-Masters' vice president of business development and chief technology officer.
In his policy letter to the government in 1991, Gellert argued that the word “toolmaker” can be broadly applied, from a master working metal to one preparing a fine meal or playing an instrument.
“Historically, the ‘toolmaker' is now and was at all times the creator of progress through the understanding of the methods of adding value to material,” he wrote.