Robert B. Brack knew from an early age that his grandfather and father hoped he would join Barker Steel Co., the business started by his grandfather in 1920.

After graduating from college in 1960 with a degree in civil engineering, he went to work at the family business. But after a few years, he left to pursue his dream of teaching math and science.

He’d return to a more challenging role at the company about a year later. At the time, the firm had one location and was barely profitable with less than $1 million in sales and twenty-eight employees.

By the time this...