The company made precision horizontal and vertical slotters, tapping attachments, and the Rotorex universal tool and cutter grinder from 1940 into the early 1950s. Their sales office was at 150 Broadway, the Westinghouse Building, New York City. The plant location is not verified. The company was founded by Henry Sonnenberg, who established a machine tool manufacturing and distribution business in Dusseldorf, Germany in 1919, moved it to Rotterdam, The Netherlands in 1933, and to the U. S. in 1940. In 1946, Sonnenberg co-founded aluminum blind manufacturer Hunter Douglas.
Information Sources
- Auction listing for an undated 8-page Douglas catalog.
- Western Machinery and Steel World, Vol. 34, 1943, pg. 113. "Plain Milling Machine. A new plain miller announced by Douglas Machinery Co., Inc., is built for accurate production work. ... Precision Slotters. Douglas Machinery Co., Inc., New York, N.Y., has developed precision slotters 7" to 10" strokes."
- Post on Practical Machinist stating that a Douglas horizontal milling machine was built by Hunter Engineering Co., Riverside, CA, for Douglas Machine Co., New York.
- Robb Report - Malaysia. Aug. 2015. Pg. 132.
- The Hunter Douglas web site has pictures of Henry Sonnenberg and a brief timeline.