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

FILE FILOSOPHY has been called soft because the operator has failed to give it a fair chance. Considerable convexity is, therefore, needed in such cases; for while it gives greater control of the file from point to heel, it also presents fewer cutting points to the work with a given pressure downward than the less convex file—the bite being increased in proportion to the increase of the convexity. The ability, therefore, to increase it more or less, at the will of the operator, is of considerable importance. In finishing many kinds of work, the absence or a suitable convexity limits the usefulness of the file—as in the preparation of the valves of steam engines, tables of printing presses, stereotype plates, or other work requiring a true surface. While an absolutely true surface is confessedly unattainable, it is evident that, as in the above cases, a degree of perfection is sometimes desirable beyond what the necessities of other work may require; and to be able to touch the exact spot indicated by the straight edge or surface plate with the file, is to utilize it in a manner which could not be done if the con- vexity did not exist. Files Properly Handled When the proper selection has been made, before using the file it should first of all be properly handled; i. e., a handle of the proper size with the proper size hole, drilled straight, should be fitted to the file, not, as is too often the case, by driving the handle half way down the NICHOLSON FILE CO. 14