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But few
tools can lay claim to as great antiquity as
the file. So very old is it, indeed,
that no mention can be found in either profane
or sacred history of its invention, for it
antedates written history; but in the Bible,
in second Samuel, the thirteenth chapter and
the twenty-first verse, is to be found the
following: "Yet they had a file for the
maddocks, and for the colters, and for the
forks, and for the axes, and to sharpen the
goads." This was 1093 years before
the advent of the Christian era, and there is
every reason to believe that the file was in
use before this time. Certain it is,
that from that time on, there are numerous
proofs to show that the file became more and
more in general use as the years went
on. In the sixteenth century it had
become so common that all reference to it was
a purely matter-of-fact way, as when Burnett,
in his "History of the Reformation,"
describing how Sir Edward Grimston escaped
from prison, thought it only necessary to say
that the cell bars were cut apart with a
file. It has only been within the past
quarter of a century that there have been
placed in operation any marked improvements in
the process of manufacturing files; and even
yet there are many mechanics who still insist
that files made by the methods of a century
ago are superior to those made by the more
modern methods of machinery. Up to
within late years this opinion has had all
points of fact in its favor, and even now it
may have some. A description of the two
processes - that is, hand and machinery, will,
therefore, be of interest.
Take the former, or hand process, to begin
with. The steel is first rolled, or tilted,
into bars of a size as nearly as possible to
the sections required. The sections
bring to the steel in the rough, which are cut
from the bar into about the length and
diameter of the file required. They are
then annealed with great care by placing them
in annealing ovens heated by charcoal, coke or
anthracite coal, until they are of a cherry
red, and then allowed to cool gradually.
This sufficiently softens them for the chisel
cutting, but very frequently after being taken
out of the oven it is found that the heat has
bent or warped them. Should this be the
case, they are forged into shape again.
They are now filed or ground, the grinding
being done on a huge stone, six feet in
diameter, the workman sitting almost astride
of it and holding the steel directly on the
stone with both hands. In olden times,
and even in years not long past, this was a
dangerous process, as the stone would
sometimes break while in motion, with fatal
results to the workman. These accidents
are rare in this country, owing both to the
care exercised by the grinders and the
superiority of the stone used. After the
blanks are ground, they are "stripped" - that
is, they are filed down to the true surface to
remove all irregularities. They are now
ready for the cutter, who sits astride a bench
in front of the block or anvil, across which
rests the file. It is held firmly in
place by a strap across either end, into the
lower loops of which are placed the cutter's
feet, like stirrups, the weight of the legs
thus firmly holding the bar in place.
The tang ( the part to be inserted into the
handle ) points toward him, and, after
slightly greasing the "blank," he is ready to
cut the teeth. In his left hand he holds
a small chisel, the edge of which always
exceeds the width of the file, and placing it
on the "blank," with an inclination of from 40
degrees to 55 degrees, according to the
character of the file to be made, he gives it
a sharp blow with the hammer in his right
hand. An indentation in the farthest or
small end of the file in thus made, the
indentation naturally inclining toward
him. This, of course, leaves a ridge, or
a tooth, slightly thrown up above the surface,
and, following this as a guide, he places his
chisel alongside of it and strikes another
blow with his hammer, and this is continued
until the teeth are cut the full length of the
face of the blank.
An average workman will strike from sixty to
eighty of these blows per minute. All
this time the file is resting on a thin sheet
of pewter, or a bed of pewter and lead mixed
together, so that the opposite side of the
file will not be injured. In cutting
round, or half-round files, the indentations
are made very narrow, say about one-tenth of
the circumference, and run in a straight line
from point to tang. Then the next
indentations are cut in the same way, but
shaped differently, the chisel being applied
as a tangent to the curve. In cutting
cross teeth, the same methods are followed -
that is, indentations are made over
indentations.
The files are now ready for tempering, or
hardening. They are first covered with a
paste, made of powdered cows' hoof and other
material, to protect them from damage while
heating, and are then heated to a red heat in
molten lead, which gives them a perfect, even
temperature, and plunged into strong
brine. From the latter they are removed
before they are entirely cold, so that they
can be straightened if necessary.
Following this, they are treated in a muriatic
acid bath and then a lime-water bath, the
first to remove all oxides and surface dirt,
the latter to remove the acid. The tangs
are then softened, after which they are
brushed with oil, and they are ready for
packing.
Two hundred years ago attempts were made to
cut files by machinery, but with no
encouragement until about 1858. Less
than thirty years ago a company, with immense
capital, was organized in Birmingham, England,
to operate the file-cutting machinery invented
by E. Bernot, a Frenchman, but the effort soon
proved a failure. The same result
followed the Prestons, of Manchester, Eng.,
and the British Patent Hardware Company, of
the same place, the machinery of the latter
being the invention of an American.
Numerous attempts were also made in Sheffield,
Eng., but partially owing to imperfections in
the cutting machines, and the opposition of
workmen to machinery of any shape or form, the
efforts proved abortive. France had also
had her file-cutting by machinery enterprises
with more or less success. This country,
however, was more fortunate in this regard,
and is quoted in the "Encyclopedia Britannica"
as the first nation ever clearly to
demonstrate that perfect files could be made
by machinery.
In the fifties, the American File Works made
files by machinery, at Ramapo, N.Y. but only
remained in business for a few years. An
attempt of the same kind in Hartford, Conn.,
in about 1857, did not succeed. Then
closely followed the Whipple File Works, of
Ballard Vale, Mass., in 1858, the Weed File
Company, and others.
The most successful was the Nicholson File
Company, of Providence, R. I., which was
organized in the spring of 1865, with W. T.
Nicholson, the inventor of their machinery, at
its head. The substantial brick
buildings were planned to admit of enlargement
from time to time, as might be required.
One of the first steps taken was to ascertain
what had been done, not only in America, but
in the old country, both in files and steel,
and to this end their agent spent several
months in Europe, with full instructions to
purchase such machinery as might be thought
worthy of adoption. These works now turn
upwards of 1,500 dozen files per day, and
their success is absolute proof of the merits
of the machine-cut file. The machinery
used by this firm is so arranged that it will
produce a file with teeth, in their spaces,
conforming to the hand-cut file. The
article produced, the company saw fit to call
the "increment cut file," the word "increment"
meaning increase. These files are not
cut a uniform depth or space, and no two
spaces can be found exactly alike in the
entire length of the side.
A
file machine, it should be understood, is a
machine that moves a "blank" quickly upon a
bed, with a chisel rapidly falling upon the
blank as it moves, and making teeth or
indentations. The clearest description
that could be given of it, is that it is
hand-work operated by machinery, for one hand
of the machine slides the blank along, while
the other sets the chisel and strikes the blow
with the hammer. The objection to
machine work, however, by those who claim to
entertain any objection, is that it is so
accurate that the teeth are cut regularly in
rows, and of a uniform depth, a thing to be
avoided in making a perfect file. In
making them by hand, however, this accuracy or
regularity, could not be obtained by the most
skilled workman, even if it was desirable, for
the force of his blows cannot always be the
same, nor can he always place his chisel
exactly in the same position.
In speaking of the variance between their
increment files and files with the regularly
cut teeth, the Nicholson File Company very
clearly explain by saying that the difference
between this and the perfect regularity of the
old machine-makes must be apparent,
particularly in the double-cut files, as in
the one case the files cut with such extreme
regularity, when put in use, will in the first
inch of its movement produce channels or
grooves, and the grooves will continue to be
made deeper as the file shoved along, thus
producing that "grooving" and "chattering" so
often complained of, while in the
"increment-cut file" the grooves made by the
movement of the file for the first inch will
have their sides cut away as the file is moved
toward the "tang" or handle, and vice
versa ; and while it is cutting as fast
as it's points will permit, it is also said to
cut smoother than the best hand-cut of the
same coarseness. The irregularity spoken
of consists not only in the spaces between
each tooth, but also in the heights of the
teeth themselves, thereby completely removing
the objections hitherto argued against machine
files.
Rasps are also made both by machinery and by
hand, the chisel for making them however,
being in the form of a three-cornered or
triangular punch. The other processes
are precisely as in file-making.
Notwithstanding the great number of files made
in this country, a file is often made over, or
sharpened- as often as three or four times,
many small concerns doing nothing but
this. The word "sharpen" in this case is
misleading, for in reality the old teeth are
ground off and new teeth chiseled in.
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