In the 1950s Duff Machine Co. of Haverhill, Mass., made lightweight vertical milling machines. Their machines are relatively uncommon. On October 22, 1958 the company was liquidated and its assets were auctioned.

Information Sources

• The lathes.co.uk site has information on Duff milling machines.
• A Google Books search turns up a handful of mentions, all of them in the 1950s.
• owwm.org discussion of a Duff milling machine, including a bit of discussion of the spindle taper.
• 1954 issue of Machinery (Volume 60 issue 2, page 1954-264): "Duff Machine Co., Haverhill, Mass. Leaflet descriptive of the Duff vertical milling machine designed with a universal head to permit easy positioning of the spindle at any angle."
• 1954 McKittrick Directory of Advertisers (Issue 76, page 1015), mentions "Duff Machine Company, Haverhill, Mass."
• 1958 issue of American Machinist (Volume 102 page 125): "Duff Machine Co, 31 Wingate St., Haverhill, Mass. Vertical miller is now available with a Bellows Air Feed for the longitudinal travel of the table. Model illustrated has 12-in. double-action Hydro Check, with a 15-in. air motor cylinder. Air motors and Hydro Check units can be supplied for 1½ to 18-in. travel (Nov 4, p198)".
• There was an unrelated company of the same name in Lowell, MA, between about 1898 and 1908. This earlier firm began by making a chain-drill attachment for a bit brace, which provides a chain that can be wrapped around a workpiece to firmly press the drill bit against it. They soon introduced a complete handheld (and hand powered) chain drill. In the course of confirming that these two companies were not related, here are some data points we found.
  • January 1899 Report of the Chief of the Massachusetts District Police, for the year ending December 31, 1898, page 203, in a table of factory inspections: "Duff Machine Co. / (goods manufactured) Drilling attachments / (number employed Males : Females : under 14 : 14 to 16) 3:-:-:- / Good / (orders given) Guard or remove projections on pulleys / (compliances) Complied."
  • August 1900 Machinery page 40: illustrated ad for "J. R. Duff's Hand Driller" showing a chain drilling attachment on a bit brace, set up to drill a pipe flange. "Duff Machine Co., 8 Western Ave., Lowell, Mass." The identical ad appeared in the August 1901 issue.
  • 1900 The Greater Boston Business Directory and Register, page 761, listing under Machinists and Machinery Manufs.: "Duff Machine Co. 136 Fletcher, Lowell".
  • 1901 issue of Iron and Machinery World (volume 89, page 23): "AN IMPROVED DRILLER—We are pleased to present herewith an illustration of an improved driller, manufactured by the Duff Machine Company (Upton & Gilman), Lowell, Mass., makers of chain ratchet drillers, Duff's chain drillers, meat tenderers, friction reversing counter, etc. This tool will fill a need for larger work than their regular bit brace drill, and can be specially used in all forms of structural iron work, drilling pipes in the ground, columns, etc. In fact, its uses are so apparent that they will immediately suggest themselves upon looking at the illustration."
  • 1906 Massachusetts Business Directory, page 802, under Machinery Mfrs & Dealers): "Duff Machine Co 587 Middlesex Lowell".
  • 1909 Hendricks' Commercial Register of the United States, page 317, under Drills, (Hand Power): "Duff Machine Co., 8 Western av., Lowell, Mass.