After graduation, he joined the John Zink Company, which his father had founded in 1929. By then, the company had specialized in manufacturing burners, flares, and incinerators for the petroleum and related industries. Jack received 35 patents for his inventions of combustion equipment. He continued to run the company from 1962 until 1979 when it was bought by
Sunbeam Corporation. After his father's company was sold, Jack purchased a small company called "Product Manufacturing" and changed the name to Zinkco. "When the new owners of the John Zink Company complained that the "Zink" name was an international trademark for combustion equipment in the same way that "Kleenex" was a trademark for tissue and "Xerox" was a trademark for photocopiers, Jack changed the name of his company to Zeeco." While their headquarters are in Tulsa, OK, the company manufactures in the United States and other global locations. Jack served on the board of directors for several companies including Telex and Sunbeam. ==Auto racing==