File

Hand tool, acting by abrasion for shaping and smoothing. A bar of soft steel of the desired section has ridges or teeth raised upon its surface by the action of an inclined chisel, which makes nicks and throws up a burr, forming the tooth. The bar is subsequently hardened. An increase-cut file is one in which those parts on which greater pre ure can be exerted are cut with ranker teeth. With respect to the coarsene of the teeth, files for metal are known as bastard, smooth, dead smooth, and double dead-smooth. Where the cutting chisel is pa ed a second time over the file-bar, cutting at the same angle with one edge which was used for the first cut with the other edge, the file is a second-cut file, and is sharper. Usual sections are flat, square, round, and half-round, for the larger sizes. Safe-edges are edges left uncut for work in slots and key-ways. Files are made by hand and by machine. promise measures affecting slavery, and F. became unpopular with Whigs and anti-slavery men by signing the Fugitive Slave Law.