A graduate of Williston Academy, Rensselaer Polytechnic Institute and Northeastern University with degrees in electrical and mechanical engineering respectively, he went on to become the chief engineer at Prophylactic Brush Company in Florence, then retired from Osley-Whitney Engineering in Westfield. Because of his lifelong interest and commitment to the field of engineering, he was highly regarded for his knowledge and called upon frequently for private consulting.
He was a pioneer in the plastics industry and an avid reader, especially technical magazines. Other interests included working on exotic cars, particularly Fiats, and spending time reading with his grandchildren and great-grandchildren.
Predeceased by his parents, William and Eunice Maginnis, wife Roslyn (Black) Maginnis and a son Michael, he leaves his children William, Jr., (Theresa), Timothy (Patricia), Stephen (Betsy), Dianne (William Dostal) and Katherine (Brian Begley) Maginnis, 11 grandchildren and eight great-grandchildren