File Filosophy
Being some Hints regarding the proper Methods of using Files and the various Applications of the most common Files

FILE FILOSOPHY the thin edges or corners are chilled so as to be harder even than the file itself. To overcome this hard scale the casting is usually pickled by the foundry before it is sent out—a process of washing the castings in acid and grinding or snagging the edges, or particularly hard parts. However, the casting, even after being pickled, retains a certain amount of sand and hardness on its surface and this will dull the best file made. Use an old file to break off this scale and clean off the casting and then a good file may be used without danger of injury to it. The necessity, therefore, of removing this scale and chilled surface becomes readily apparent, and all mechanics who give any consideration to the proper and economical use of the file will be careful to see that the scale and sand are first removed by pickling, and the surfaces which have become chilled by grinding, before applying the file. When Oil Should Not Be Used All files, when they leave the manufactory, are covered with oil to prevent them from rusting. While this is not objectionable for many uses to which the file is put, there are cases where the oil should be thoroughly removed, as when the file is to be used in finishing the larger cast iron surfaces which are of a glassy nature; the principal difficulty being to make the file “bite,” or keep sufficiently under the surface to prevent glazing; otherwise the action not only hardens or burnishes the surface operated upon, but NICHOLSON FILE CO 24