Whirling Concrete Poles into Shape £^ 



THE principle of centrifugal action 

 utilized in a machine invented by 



Centrifugal action is set up and the liquid 

 concrete is thrown against the tubular frame 



Walter H. Lienesch, of Chicago, 

 makes possible the production of substan- 

 tial, attractive and inexpensive lamp poles, 

 telegraph poles and sign posts from re- 

 inforced concrete. 



The machine consists of an outer cylin- 

 drical frame which carries the mold and 

 which is constructed of sheet metal, formed 

 from two half-cylinders hinged together. 

 Within this carrier-frame is a smaller mold-' 

 cylinder, of tapering, rather than of true 

 cylindrical form. This mold is likewise 

 constructed from two half-cylinders of sheet 

 metal, hinged together. The inner mold 

 is supported by braces carried within the 

 outer carrier-frame or cylinder. 



Both frames are opened and concrete 

 is poured into the 

 inner mold cylin- 

 der to partly fill it, 

 reinforcing wire 

 netting having 

 been placed in 

 the mold first. 

 The mold 

 and the outer 

 carrier -cylinder 

 are then bolted or 

 latched together. 



The concrete lamp posts are unusually- 

 attractive and are made in different styles 



A motor which is connected with the 

 carrier-frame by a flexible shaft is started 

 up, and carrier-frame and mold are rapidly 

 rotated axially. The resulting centrifugal 

 action whirls the concrete compactly 

 against the cylindrical mold sides to form 

 a tubular pole. The operation is continued 

 long enough to allow the concrete to harden. 

 The machine is then stopped and the newly 

 formed concrete pole is removed. Poles of 

 almost every type can be thus formed. 



A telegraph pole of 

 concrete recently 

 erected in Milwaukee. 

 It will probably be 

 doing as good service 

 as now one hundred 

 years from today 



The mold is constructed of comparatively thin metal and is light in 

 weight so that it can be readily removed from the carrier-frame 

 after the pole has been completed and is ready to set up 



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