IMPROVEMENTS IN THE MANUFACTURE OF FILES
Year: 1850

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CHARLES
COWPER, of No, 20, Southampton Buildings, Chancery Lane, in the County
of Middlesex, Patent Agent, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Nineteenth day of
December (One thousand eight hundred and fifty), in the fourteenth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Charles Cowper, my exors, adiñors, and assigns, Her especial licence.
full power, sole privilege and authority, that I, the said Charles Cowper, my
exors, adñiors, and assigns, or such others as I, the said Charles Cowper, my
exors, admors, or assigns, should at any time agree with, and no others, from time
to time and at all times during the term of years therein expressed, should
and lawfully might make, use, exercise, and vend, within England, Wales, and
the Town of Berwick-upon-Tweed, in the Islands of Guernsey, Jersey, Alder-
ney, Sark, and Man, and in all Her said Majesty's Colonies and Plantations
abroad, the Invention of "IMPROVEMENTS IN THE MANUFACTURE OF FILES,"
communicated to me by a certain Foreigner residing abroad; in which said
Letters Patent is contained a proviso that I, the said Charles Cowper, shall
cause a particular description of the nature of the said Invention, and in
what manner the same is to be performed, by an instrument in writing
under my hand and seal, to be inrolled in Her Majesty's High Court of
Chancery within six calendar months next and immediately after the date
of the said in part recited Letters Patent, as in and by the same, reference
being thereunto had, will more fully and at large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
Charles Cowper, do hereby declare that the nature of the said Invention, and
the manner in which the same is to be performed, are fully described and ascer-
tained in and by the following statement thereof, reference being had to the
Drawing hereunto annexed, and to the figures and letters marked thereon,
that is to say:
The Invention relates to improvements in the teeth of files, and in the
method of forming them.
Figure 1 of the Drawing hereunto annexed is a perspective view of an
ordinary file, and will serve to explain the ordinary method of cutting it or
of forming the teeth. A, B, is the pile. C shows the position in which the
chisel is held while making the first series of cuts. The chisel is struck by a
hammer, which is either held in the hand of the workman or set in motion
machinery, and the file or the chisel being advanced a little after each
blow a regular series of diagonal transverse cuts are produced from one end
to the other of the file. The surface is slightly smoothed over by a file
or otherwise, and the second series of cuts is then made in a similar manner.
D is the position of the chisel while making the second series of cuts. It
will be seen that in both cases the chisels are inclined in the same direction,
or in other words, the angles of inclination I, H, K, and F, E, G, are both
on the same side of the perpendicular.
Now in operating according to the present Invention the two series of cuts,
in lieu of being inclined in similar directions as in Figure 1, are inclined in
opposite directions, as shown in Figure 2, in which A, B, is a perspective
view of the file. The chisel C is here inclined in the opposite direction
to that marked C in Figure 1, the angle I, H, K, being on the contrary
side of the perpendicular, or, in other words, inclined towards the contrary
end of the file. The first series of cuts having been made with the chisel in
this position, the surface is carefully smoothed to remove any excessive
projections or roughnesses, and the second series of cuts is then made with
the chisel in the position shewn at D in Figure 2, the angle F, E, G, being
on the opposite side of the perpendicular, so that, as already stated, the
inclinations of the two series of cuts are in opposite directions. It will be
found that files cut in this manner clear themselves of the filings, and cut
better and with much less labour than files made in the ordinary manner.
The metal is also strongly compressed or hardened by this method of cutting,
which renders it possible to form the teeth with such depths and inclinations
as to produce stronger and sharper cutting teeth than is the case when
operating in the ordinary manner.

page_text: The improved files may be cut either by hand or by machinery, or one series
of cuts may be made by machinery and the other by hand. The following
method may also be used with advantage for producing the first series of cuts :-
A steel die is formed, with a cavity of the shape and size of the file, and in the
bottom of this cavity a series of grooves and ridges are formed, so that the die is
a counterpart of one side of the file after it has received the first series of cuts.
Another die is made, which is the counterpart of the other side of the file. A
file blank being heated red hot is placed in the first die, and the other die is
then brought forcibly down upon it by means of the blow of a hammer, or by a
fly press or crank or cam, or other suitable means. The first series of cuts
will thus be at once formed on both sides of the file, which afterwards receives
the second series of cuts by machinery or by hand in the usual manner. This
mode of producing the cuts is applicable to the manufacture of ordinary files,
as well as of the improved files herein-before described. When it is desired
to produce a series of cuts on one side only of the file by this method, one of
the dies is made with a blank or smooth surface.
Having now described the nature of the Invention, and in what manner
the same is to be performed, I wish it to be understood that I claim the
manufacturing of files with two series of cuts inclined towards the opposite
ends of the file, as herein-before described.
And I also claim the mode or modes of forming the teeth of files by means
of dies, as herein before described.
In witness whereof, I, the said Charles Cowper, have hereunto set my
hand and seal, this Seventeenth day of June, in the year of our Lord
One thousand eight hundred and fifty-one