Improvements in Files..
Year: 1898

page_text: Improvements in Files..
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7
I, JOHN RUSSELL, of Canton Works, Shude Lane, City of Sheffield, File Manu.
facturer, do hereby declare the nature of my invention t be as follows:
My invention of improvements in files, relates more particularly to the cutting
of the teeth of such implements, it is of special advantage to files for filing brass
and brass alloys, and is of advantage in the cutting of files for other purposes.
It consists in cutting one set of teeth obliquely across the file in the usual
manner and making the cross cuts also oblique in the opposite direction but at
a much greater distance apart than usual for example I omit two cuts of ordinary
width after cutting the first tooth and then cut the second, thus there would be
four cuts or teeth, where there would be ten cuts or teeth if cut in the usual
manner. I do not however bind myself to this precise distance.
I prefer to make these separated cuts first or what are known as the overcuts,
and the regular teeth as the second or upcuts, but I may reverse this arrangement
if I think it advisable.
I may also reverse the angles of each cut so as to produce a right hand or
left hand file.
I find by experiments and tests with files cut according to my invention, that
I obtain a keener cutting quality and that the teeth do not clog as soon as those
of files cut in the ordinary manner.
1
L 1000
ROBT. F. DRURY, C.P.A.,
Agent for Applicant, Bank Buildings, George Street, Sheffield.
Improvements in Files.
I, JOHN RUSSELL, of Canton Works, Shude Lane, City of Sheffield, File Manu-
facturer, do hereby declare the nature of this invention and in what manner
the same has to be performed, to be particularly described and ascertained in and
by the following statement:-
My invention of improvements in files, relates more particularly to the arrange-
ment or cut of the two sets of teeth, commonly known as the "overcut" and the
upcut"; it is of special advantage to files used upon brass and brass alloys, but
is also of advantage to files for other purposes.
"
The arrangement of the teeth is shown in the annexed sheet of drawings, in
which

page_text: Fig. 1, represents a portion of the tang end of a file cut upon my improved
plan.
Fig. 2, represents a modification of same.
The invention which is the result of many experiments consists in cutting one
of the sets of teeth marked A, in the usual manner obliquely across the file, and
another set B, cut obliquely in the opposite direction or angle but having a
much greater space between them than is usual.
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In carrying my invention into practice I prefer to commence with the series of
teeth marked B, which are known to the trade as the overcuts," while those
marked A, are called the "upcuts," but this arrangement may be reversed if
desired.
Having cut the first tooth, I cut the second at about the distance of the fourth
ordinary tooth, leaving a blank space in which two ordinary teeth such as A,
could be placed or thereabouts, thus the fourth B tooth would be the same
distance from the first as the tenth ordinary tooth would be.
But I wish it to be clearly understood that although the proportion of space
between the teeth B, compared with the teeth A, are what I prefer, I do not
bind myself to this exact relative proportion, which it will be obvious to practical
men, may be varied in either direction, I may also if desirable reverse the angle
of the teeth, so as to make a right and a left hand file.
Neither do I confine myself to the use of single teeth as shown in Fig. 1, but
for some purposes I may use a series of double teeth B as shown in Fig. 2 with
broad spaces between them and the next pair.
According to tests made with files cut according to my invention, I obtain a
better cutting quality, and the teeth do not clog as quickly as those of files cut
in the ordinary manner.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed I declare that what
I claim is:-
A file having one series of its teeth, (such as those marked A) cut in the usual
manner, and the other series (such as B) of either single or double teeth, cut at a
distance apart of about three times that of the teeth marked A, as hereinbefore
described and set forth.
D
1
00. 1 1
CT
1000
the 22nd day
1000
ROBT. F. DRURY, C.P.A.,
Agent for Applicant, Bank Buildings, George Street, Sheffield.