Frank Sandberg Jr. loved railroading, but declined to pursue it as a career. A job with a railroad might ruin his hobby.
Instead, he became a design engineer, creating machines that would in turn make everything from refrigerator systems to automobile steering wheels.
However, as a hobbyist, he would still play key roles in preserving the state's railroad history.
Sandberg, a Minneapolis native who lived in Shoreview, died June 13 of a heart attack. He was 76.
He graduated from Roosevelt High School in south Minneapolis and then went to Dunwoody.
After serving in the Army National Guard, he landed his first job in the early 1960s at Remmele Engineering, then located in St. Paul.
In 1983, Sandberg and a few other engineers left Remmele to create Con-Tek Machine in White Bear Lake.
The company designed and built machines used to manufacture components for many industries, including wing panels for the stealth bomber.
Sandberg was Con-Tek's president and chairman until he retired in 2015.
He also had a passion for trains that went back to childhood.
Sandberg's father worked for the Milwaukee Road from 1917 to 1970. The engineer sometimes took his young son to work, a thrill for the boy.
"They would ride all summer in the cab of the locomotive," said Steve Sandberg, Frank Jr.'s son and himself a railroad buff.
Steve once asked his dad why he didn't get into railroading himself, and Frank replied simply, "Because I loved it too much."
"He felt that if it became a job, he wouldn't like it as much," his son said. "He wanted to keep it fun."
Frank Sandberg's wife, Judy, whom he met in high school choir, also became a railroad aficionado.
Together, they helped create the Minnesota Transportation Museum, which today is headquartered at the Jackson Depot, a 111-year-old roundhouse in St. Paul that hosts several vintage rail cars.
The Sandbergs also helped establish and build the Como-Harriet Streetcar Line in the early 1970s, restoring a 1950s-vintage Minneapolis trolley car. It still operates between Lake Harriet and Bde Maka Ska (Lake Calhoun) in southwest Minneapolis.
A separate Minnesota Streetcar Museum later grew out of the Minnesota Transportation Museum's work.
For the past 25 years, Frank Sandberg also had been chairman of the nonprofit Railroading Heritage of Midwest America, which owns a fleet of historic railroad cars and a restored 1944 locomotive.
The steam engine, the Milwaukee Road No. 261, was once piloted by Sandberg's father.
Steve Sandberg coordinated the rebuilding of No. 261 in the early 1990s, and today is president of Railroading Heritage.
It's particularly known for its short North Pole Express ride out of St. Paul's Union Station during the holiday season.
Frank Sandberg was preceded in death by his wife, Judy Sandberg. He is survived by his daughter Catherine Walker (also a railroad enthusiast) and son Steven, as well as their spouses and three grandchildren.
Services have been held.