The Minnesota Mining and Manufacturing Company relocated from Duluth to Saint Paul in 1910 and housed all of its offices and manufacturing operations in one small building on Forest Street by the railroad tracks in Dayton's Bluff. Success with sandpapers led to expansion into a second building by 1919, with offices on the second floor. The development of Wetordry sandpaper in 1921 and Scotch masking tape in 1925 brought sustained growth, and new plant buildings were added, including Building 3 in 1923, Building 12 in 1928, the first stage of Building 14 in 1929 on Fauquier Avenue west of Building 2, and Building 20 west of Building 14. As products and sales increased, more office and factory space was needed. In 1937, company president William L. McKnight announced a half million dollar expansion program that included Building 20 for manufacturing in 1937-1938 and Building 21 as new administrative offices in 1939-1940. Over the following decade, Buildings 22, 23, and 24 were built for tape research and manufacturing. After a major reorganization in 1948, Building 42 was constructed in 1950-1951 to house the expanding office staff, sales departments, and division heads. As the company grew, it acquired neighborhood properties and demolished existing houses for Building 24, the water tower, and an adjoining parking lot. The administrative complex became the hub for company strategies in research, product development, and product diversification, and it also housed the international division headquarters. The company headquarters moved to a new building at the 3M Center in Maplewood in 1962, while the Saint Paul Plant remained in active use until 2009.
