IMPROVEMENTS IN THE MANUFACTURE OF FILES
Year: 1865

page_text: LETTERS PATENT to William Boxer Newbery, a British subject resident
at Boston, in the County of Suffolk, in the State of Massachusetts, one
of the United States of America, for the Invention of "IMPROVEMENTS IN
THE MANUFACTURE OF FILES."-A communication from Moses Griffin
COMPLETE SPECIFICATION filed by the said William Boxer Newbery
at the Office of the Commissioners of Patents, with his Petition and
Declaration, on the 14th February 1865, pursuant to the 9th Section of
the Patent Law Amendment Act, 1852.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
BOXER NEWBERY, a British subject resident at Boston, in the County of
Suffolk, in the State of Massachusetts, in the United States of America, send
greeting.
WHEREAS I am in possession of an Invention for "IMPROVEMENTS IN THE
MANUFACTURE OF FILES," and have petitioned Her Majesty to grant unto me,
my executors, administrators, and assigns, Her Royal Letters Patent for the
same, and have made solemn Declaration that the same is a communication
to me from Moses Griffin Crane, a person resident in Chelsea, in the aforesaid
County.

page_text: NOW KNOW YE, that I, the said William Boxer Newbery, do hereby
declare that the following Complete Specification under my hand and seal
fully describes and ascertains the nature of the said Invention, and in what
manner the same is to be performed, in and by the following statement:-
Of said Drawings Figure 1 is a plan of a machine embodying my Invention,
and arranged for cutting files of a circular or of a generally curvilinear cross
section; Figure 2 is a side elevation of said machine with two of the three
cutter bearers, shown in Figure 1, removed; Figure 3 shows one of the cutters
and its guage, together with the parts immediately therewith connected, all
in section; and, Figure 4 is an end view of one of the cutter and guage
bearers.
My Invention consists in a file-cutting machine so organized that by angular
adjustment of the cutters relative to the axis of the file when in position to be
cut, and by rotation of the file, or by the rotation of the cutters around the
file, a continuous thread or threads, forming the teeth of the file, shall be
formed on the file blank, passing around it in a spiral direction or in the
manner of a screw thread. In the organization of a machine to embrace my
Invention I prefer to rotate the file blank as being much simpler than rotation
of the cutters around the blank. Either of said rotations, with the angular
arrangement of the cutters, effects automatic longitudinal motion of the file
blank, though the organization might be such as to allow the file blank to
remain at rest as to movement in direction of its length, in which case the
cutter would move along the length of the file.
And my Invention further consists in the employment, in connection with
a cutter of a guage so. arranged relatively to said cutter as to bear on the
uncut surface of the file blank, and thus regulate the depth of the cut, and so
that while performing said function sufficient space is given between the
cutter and the guage for the reception of the burr or tooth raised by the action
of the cutter.
And my Invention further consists in making said guage adjustable relative
to the edge of the cutter; also in making the angle of the cutter adjustable
with respect to the axis of the file blank, and furthermore in certain details of
construction which will be referred to beyond. The machine shown in the
Drawings is one which is arranged for cutting round taper files, the file blank
being made to rotate and the cutters being fixed except with respect to
independent rotation of each on its own axis and movement toward and from
the axis of the file blank.
The framework of the machine and the gearing by which the file blank is
rotated are easily enough understood from the Drawings. Said gearing rotates

page_text: a slotted sleeve a, within which is a chuck in which the file blank c is held
by a set screw d, the chuck b being made to slide freely up and down in the
sleeve a, but prevented from turning therein; then the file blank is made to
rotate while it is free to move longitudinally. On the top plate of the machine,.
and arranged, around the centre of the sleeve a, are supports e for the tooth-
forming mechanism. Each support hás cylindrical bearings therein which
receive a cylindrical spindle made up of two parts, an upper part f and a lower
part ġ, which, while they must turn together and must move back and forth.
together, are yet adjustable in a longitudinal direction with respect to each
other by means of the set screws h. The upper half of the spindle has pivoted
thereunto the cutter i and the lower half the guage j, both being disc-like
pieces, the former of steel suitably sharpened and tempered. The guage is
bevilled, as shown, to clear the burr or tooth thrown up by the action of the:
cutter, or it may be set a little distance off from the cutter. Coiled around.f
and g, and between washers placed thereupon, the washer nearest the file,..
bearing on pins or in the upper and one in the lower part of the spindle, is a
stout spiral spring which acts always to force forward the cutter and guage.
toward the file. The amount of pressure which the spring is made to exert is.
regulated by adjustment of the set screws k, care being taken in order to
secure uniformity of cut that the pressure is sufficient to bring the guage in
contact with the uncut surface of the file blank even in the hardest places.
which may exist therein. It will be obvious that the position of the guage
relative to the cutter edge determines the height or depth of the cut,, which,
must be uniform from one end of the file to the other unless the relative.
positions of the guage and cutter are changed, which may be done during the
cutting of a file if, as is sometimes the case, it is desirable to make the file
teeth, deeper at the middle of a file than they are at the heel or point.. To.
give any desired angle of the cutter to the axis of the tube a a T-shaped
lever is pivoted to the support e at m. In this lever are two slots at about
right angles to each other, one slot n embracing a pin o which is fixed in and
projects from f. Now by inspection of Figure 1 it will be seen that as the
lever is swung one side or the other, the spindle f, g, must be turned thereby
to a greater or less extent, according to the amount of sidewise movement of
the lever 1; and furthermore, that it is by this partial rotation of said spindle
that the cutter is set and adjusted to any needed angle, the set screw p
confining the lever wherever needed. Any suitable number of cutting me-
chanisms substantially similar to that just described may be arranged around
a common centre. On reference to Figure 1 three will there be seen which,
pressing toward a common centre, form beds (each of which receives the pres-

page_text: sure from the other) and hold the file blank submitted to their action centrally
between them, thus doing away with the need of soft metal beds or supports.
An organization by which the stress exerted by one rotary cutter on a file
blank is counteracted by stress exerted in an opposite direction by another, or
other rotary disc cutters, constitutes another part of my Invention. By it I am
enabled to be cutting on the same blank at two or more places at the same
time, or to use several cutters for increasing the size of one gash or cut, using
all the time as a fixed and unchangeable guage the uncut surface of the blank,
which is the only guage which can be successfully used with any certainty of
securing teeth of a uniform or of a desired depth in file cutting. To the
angular set of the cutters is due the longitudinal progression of the file blank
while rotating, this being effected in the same manner and for the same
reasons that a rod moves longitudinally through a screw die, while the latter
is rotated and kept from any other movement. It is an advantage in taper
files to have the teeth at the small end finer than at the middle or large part
of the file; this the detail of construction shown in the Drawings, especially
in Figure 1, effects, for it must be obvious, from inspection of said Figure,
that the nearer each cutter approaches the common centre the less will be the
angle given the cutter from the position of the pin o in the slot n, and it will
be understood that the less the angle of the cutter the less will be the advance
of the file and the finer will be the teeth, and vice versa. In files which are
formed from heel to point of equal diameter, if it is desired to have the teeth
cut finer at either or both ends than in the middle, means may be applied to
the spindles f, g, to turn them automatically or by hand, so as to change the
angle of the cutters. As it is considered by some mechanicians that too great
regularity in the spacing of the teeth is apt to produce a vibrating or chat-
tering action of the file the spacing of the teeth may be made as irregular as
is needed by changing the angles of the cutters.
Part of my Invention consists in the means described for changing the angle
or pitch of the file teeth, also in the means described, or in any equivalents
therefor, which operate to change the angle of the cutter from any pitch to a
less pitch, or from any pitch to a greater pitch, so as to make the teeth finer
upon the small diameters of a file than they are on its large diameter.
And my Invention further consists in the manufacture of files which have
their teeth formed by cuts in a spiral direction, like the threads of a screw
except that the teeth are burrs formed by displacement of material, and are no
like screw threads formed either by removal or by addition of material. I
but a single cutter is used then there should be one or more pressure rolls
arranged opposite to receive the stress of the cutting, but this, on account o

page_text: needlessly slow working, should never be done in practice. The screw which
is formed around the file will be single, double, triple, quadruple, and so on,
according to the number of cutters employed and their adjustment. To adjust
the cutters so as to have each form a separate thread, and so as to have them
all a proper distance apart, the carriages e can be, adjusted in height by the
screws shown in dotted lines in Figure 2. When the screw thread or threads
have a regular gain or pitch from one to the other end of a file the throwing
up of the burr or burrs which form the thread or threads may be increased, if
desired, by giving to the file blank a regular positive progression very slightly
in excess of what the file would receive from the operation of the inclined
cutters. In connection with each cutter and guage-bearing spindle there
should be some convenient system of levers to draw back the cutters and
guages from each file to release it when cut, and in some cases to enter uncut
blanks between the cutters. No such arrangement is shown in the Drawings
because it would only complicate and confuse them, and it is obvious that any
competent mechanic could, without Invention, make such an obvious appliance.
It will be seen that by the mechanism described several "half-round files,""
technically so called, can be cut by making the machine of sufficient size and
employing a suitable polygonal spindle, to which the files are secured with
their flat faces against the faces of the spindle. So far as described the files
cut by my machine are float or single cut, but it is plain that when cut one
way they may be cross-cut in another similar machine, in which the angle of
the cutters is reversed, and in which the guages are made of material which
bearing on the previously cut teeth will not harm them. By uniformity of
cut which I make, and the fact that the teeth are not short cuts, which, being
on a curved surface, are necessarily highest in the middle of each little cut,
I produce very cheaply a superior file.
To operate the mechanism herein described as embodying my Invention,
the cutters are first drawn back and a file blank is introduced into the tube a
and is secured by its tang in the chuck b, which is then brought upward till
that part of the file where the cutting is to begin is placed opposite to the
cutters, which are released from control and bear upon the blank. Rotation
now of the crank in the proper direction will cause the file blank to turn so
as to advance by the contact therewith of the cutters, these rotating as the
file blank rotates. When the body of the file blank is cut as near to the tang
as is desirable rotation is stopped, the cutters are drawn back, and the cut
blank is released from the chuck, which is then in readiness to receive a new
blank, on which the described operation is to be repeated.
For cutting files of polygonal cross section I make use of a mechanism such

page_text: as is shown in plan in Figure 5, and in elevation in Figure 6, while Figure 7
is a rear end view of one of the cutter and guage bearers.
The arrangement shown in Figure 5 is one adapted for cutting triangular
files, and it is easy to be seen how obviously the arrangement must be modified
for cutting files of any given greater number of sides. The cutters shown are
of the chisel kind with guages to correspond, and are arranged angularly to
the axis of the file, the angular arrangement being most clearly shown by the
detail, Figure 7. The chuck is made to move up and down to cause the file
to progress under the action of the cutters, but does not rotate as before
described in the arrangement for cutting files of a round or generally curvi-
linear form of cross section. The sleeve a is rotated by a mechanism the
operation of which is obvious on inspectien of Figure 6, but such rotation is
for the sole purpose of giving motion to cam q, which acting on the pins r
causes, in connection with the spiral springs s, reciprocations of the cutters
and guage.
It will be observed that by the particular means shown for reci-
procating the chuck b, seen in Figure 6, the feed movement of the blank held
therein will be less at its ends than it is at the centre, by which the teeth
produced will vary in spacing or in degree of coarseness or fineness accordingly;
also that by the angular arrangement of the cutters they can all operate, each
to form one tooth at the same time (all reacting on each other so as to
support the file without any other bed) each tooth being cut cleanly to the
edges or angles of the file without contact of one cutter with another.
I claim the manufacture of curvilinear surfaced files with teeth which have
the direction of screw threads when these are thrown up as burrs from the
surface of the file blanks to substantially a uniform distance therefrom. /
Also a file-cutting mechanism so organized that by having a cutter or
cutters arranged angularly to the axis around which the blank is cut, and by
rotation of the blank, or of the cutters around the blank, the file shall be cut
along its length, substantially as and for the
purpose described.
Also the employment, in connection with a file-blank cutter, of a guage in
such manner as to regulate the depth of the cut by contact with the uncut
surface of the blank, and so as not to interfere with the burr or tooth raised
by the cut, substantially as and for the purpose described.
Also making such guage adjustable with respet to the edge of the cutter,
substantially as and for the purpose specified.
Also varying the angle of the cutters while operating to form the file teeth,
substantially as specified.
And the arrangement of two or more circular or disc cufters with respect
to each other and to the blank being cut so that the stress exerted by each

page_text: cutter is resisted by the other or the others, substantially as and for the
purpose described.
In witness whereof, I, the said William Boxer Newbery, have hereunto
set my hand and seal, this Twenty-fourth day of January, A.D. 1865.
Witnesses,
J. B. CROSBY.
F. GOULD.
W. B. NEWBERY. (L.S.)