Types and Uses

TM 9-243 TYPES AND USES Files are used for cutting, smoothing off, or removing small amounts of metal, wood, plastic, or other material. Files are made in various lengths, shapes, and cuts. Every file has five parts: the point (1), edge (2), face or cutting teeth(3), heel or shoulder (4) and tang (5). The tang is used to attach the handle on American pattern files. The tang is shaped into a handle and is usually knurled on Swiss pattern files. AMERICAN PATTERN FILE American pattern files are generally used for fast removal of material and where a precision finish is not required. Grades of coarseness are bastard-cut for heavier work (1), second-cut (2) and smooth-cut (3) for finishing work, and dead smooth-cut (4) for an extra fine finish. American pattern files come with single-cut (5), double-cut (6), or curved-cut teeth (7). Single-cut files are used with light pressure for smooth surfaces or to put a keen edge on cutting surfaces. Double-cut files are used under heavier pressure and where a rougher finish is permissible. Curved-tooth files are cut in a contour across the face and are used to smooth surfaces on aluminum, bronze, lead, babbitt, zinc, and plastics. MILL FILE Mill files are tapered to the point in width and thickness for about one-third of their lengths. They are single-cut with one uncut edge. They are used to sharpen mill or circular saws, and for draw-filing or finishing metals. PILLAR FILE Pillar files are similar to hand files in general shape, but are much narrower. They are double-cut with one uncut edge. Pillar files are used to file in slots and keyways. ROUND FILE Round files taper slightly toward the point. Bastard-cut files 6 inches and longer are double-cut. The second-cut files, 12 inches and longer, are double cut. All others are single-cut. Round files are used for filing circular openings or concave surfaces. SQUARE FILE Square files taper slightly toward the point on all four sides and are double-cut. They are used for filing rec- tangular slots and keyways. TAPER FILE Taper files, or triangular files, are tapered toward the point on all three sides. They are used for filing saws having 60 degree angle teeth. Taper files come in regu- lar, slim, extra slim, and double extra slim and usually are single-cut. THREE-SQUARE FILE Three-square files are tapered toward the point on all three sides and are double-cut. They are used for filing internal angles, and for cleaning out square corners. 28-2