In the 1880s E. Densmore (Edwin Densmore) was manufacturing patent lumber trimmers and veneer slicing machines. The lumber trimmer design was covered by an 1874 patent granted to James Allen of Allegon, Michigan. The veneer trimmer—a very successful design—was patented by Densmore in 1886, with an improvement patented in 1891.

From September 1887 The Wood-Worker

In 1887 Densmore sold his business to another local woodworking machinery manufacturer, the Michigan Iron Works.

• 1868-69 Dudley & Goldsmith's Directory of the City of Grand Rapids has no listing for a Densmore.
• 1872-3 Godfrey's Annual City Directory of Grand Rapids has no listing for a Densmore.
• 1873-74 Burch, Polk & Co.'s Grand Rapids Directory has no listing for a Densmore.
• 1874-75 Polk, Murphy & Co.'s Grand Rapids City Directory has a text ad: "E. Densmore, Producers' and Manufacturers' Agent for all kinds of Lubricating Oils. Office, 124 Monroe Street. Grand Rapids, Mich."
• 1875 Murphy & Co.'s Grand Rapids City Directory lists "Densmore E. & Co., (Edwin Densmore, Louisa Shead) dealers in machinery and mill supplies, 77 Canal.
• 1876-7 Murphy & Co.'s Grand Rapids City and Kent County Directory lists "Densmore Edwin, mill machinery, 75 Canal, res. 13 Grinnell Block.
• 1879-80 R. L. Polk & Co.'s Grand Rapids City Directory has no listing for Densmore.
• 1881 R. L. Polk & Co.'s Grand Rapids City Directory has no listing for Densmore.
• 1880-81 R. L. Polk & Co.'s Grand Rapids City Directory has no listing for Densmore.
• 1883 R. L. Polk & Co.'s Michigan State Gazetteer and Business Directory lists Edwin Densmore as treasurer of the Grand Rapids Veneer & Panel Co., and as a partner in George F. Murray & Co., manufacturers of wagon and carriage hubs.
• September 1887 The Wood-Worker. "E. Densmore, Grand Rapids, has sold his veneer machine interests to the Michigan Iron Works, of Grand Rapids, who will continue to manufacture them."
• October 1887 The Wood-Worker. "E. Densmore, who has been in the manufacturer of veneer machines at Grand Rapids, Mich., has sold out to the Michigan Iron Works, of that city, who will in the future make his machines. The Densmore machine is one of the best in the market."
• 1891 R. L. Polk & Co.'s Grand Rapids Directory has no listing for an E. Densmore.
• 1889 book, The City of Grand Rapids, Manufacturing Advantages Commercial Importance... mentions that E. Densmore was a co-founder of the Grand Rapids Portable House Co., established 1886. The writeup concludes of their portable houses, "letters patent having been issued to E. Densmore, May 21, 1886."
• 1918 The National Cyclopedia of American Biography, Volume XVI has a biography of one Joseph H. Spires. In about 1900 "He organized the Yucca Manufacturing Co. with Edwin Densmore..." Another biography of Spires asys that the company was formed "to utilize the fiber of the Yucca plant", and it seems likely this was a California-based business.