| US Patent: 679,927 
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| Method of Making Screws | 
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| Patentee: |  |
 | William A. Warman (exact or similar names) - Rochester, NY |  
 
 
 
 
 
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| Patent Dates: |  
| Applied: | Apr. 04, 1900 |  
| Granted: | Aug. 06, 1901 |  
 
USPTO (New site tip)| Patent Pictures:
	      
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			1 | 2
	        ] |  |  |  | William A. Warman patent Aug. 6, 1901 |  Google Patents
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                        Stan Schulz
 
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| Description: |  | The patent describes a method of forming hollow set screws by drawing sheet metal. Dies would shape the exterior of the screws; the interior would be formed by "irregular polygonal mandrel" matching the shape of the wrench would be used.
Hammacher, Schlemmer & Co. advertised as "sole agent" for these screws in 1905. In that ad and the patent drawing, the mandrel / wrench is hexagonal. |  |