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.
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