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Making Chuck Springs
George Langford, Sc.D.
February 2, 2009; copyright 2009

Henry Hjorth patented a spring-winding tool in 1907, many of which find their way into the antique tool market. I've recently been commissioned to make a set of springs for a late-model Millers Falls No.2 eggbeater drill, so I took the occasion to document how it's done.  There are no instructions on the use of the Hjorth spring winder tool published anywhere on the Internet, so I took advantage of Google's Patent Search feature to find the best instructions of all.  However, the PDF file that Google provides is difficult to read, and the US Patent Office's patent images are in a non-standard TIFF format, so I employed optical character recognition to make a browsable version of the text from Google's PDF version of the patent, and I used The Gimp's ability to open and edit PDF images to condense the patent drawings into JPG format as shown below.  The DATAMP (Directory of American Machinery and Tool Patents) site has some additional history on this tool and the Hjorth patent.

Henry Hjorth wire-winding tool, US Patent No. 861,283
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