Improved Method of Setting Diamonds and like Hard Stones in Cutting Tools and the like.
Year: 1899

page_text: Date of Application, 29th Nov., 1899
Complete Specification Left, 29th Aug., 1900-Accepted, 29th Sept., 1900
Improved Method of Setting Diamonds and like Hard Stones in
Cutting Tools and the like.
I, JOHN CORRIGAN, of 2, Weymouth Street, Chorlton-on-Medlock, Manchester,
in the County of Lancaster, Machinist, do hereby declare the nature of this
invention to be as follows:-
This invention relates to an improved method of setting diamonds and similar
hard stones in stone cutting or boring tools saws, and the like, and consists
principally of improved means of setting or fixing each diamond or other hard
stone in a plate or plug of steel whereby it is attached to the cutting or other
tool.
'
According to my invention I take a small steel plug or plate of a convenient
shape or width to hold the diamond or stone and of a sufficient thickness to
contain the diamond or stone and leave a sufficiency of metal on all sides, say,
for example, about three quarters of an inch long by half an inch wide and about
three sixteenths to a quarter thick. I then file cut away or otherwise reduce
this thickness to about one half leaving a flange or shoulder of the full thick-
ness across one end. I then drill a hole through the centre of this thick end in
a sloping direction, beginning in the angle of the flange or shoulder and pass-
ing out at the angle. The hole is drilled with a slightly conical tool so that the
orifice at the external angle is smaller than that in the inner angle between the
flange and the plate.
I then take a piece of diamond of a wedge shape to fit this hole and I drive
it into the hole in the steel plug until its smaller end protrudes through the
outer hole in the angle of the plug.
I next take a smaller plate or plug, of steel about half the thickness of the
original one, and of about the same width, and place it with one end against
the butt end of the diamond or stone, and whilst it is thus held firmly in position
I rivet the two plates together, and thus the diamond or stone is securely set,
embedded and held in the steel plate or plug with its smaller cutting end
protruding from one angle of the same.
The diamonds or other hard stones thus set or secured in the small steel plates
or plugs, may be fixed in saws or other cutting or boring tools.
I would remark that each plug, disc, or plate, maye have one or more diamonds
inserted therein, in any suitable position or at any angle required.
Or instead of drilling holes in the plates as aforesaid, the diamond holder may
be formed of two plates, the ends of which may be provided with conical slits
or indents into which the wedge or oval formed diamonds are inserted leaving
the cutting part projecting therefrom, and the two plates are then rivetted,
clamped or brazed together, thus locking the diamonds securely in position.
Dated this 28th day of November 1899

page_text: Improved Method of Setting Diamonds and like Hard Stones in
Cutting Tools and the like.
I, JOHN CORRIGAN, of 2, Weymouth Street, Chorlton-on-Medlock, Manchester,
in the County of Lancaster, Machinist, do hereby declare the nature of this
invention and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement: —
This invention relates to an improved method of setting diamonds and similar
hard stones in stone cutting or boring tools saws, and the like, and consists
principally of improved means of setting or fixing each diamond or other hard
'stone in a plate or plug of steel whereby it is attached to the cutting or other
tool.
The object of my invention is to prevent the diamonds that are employed in
various kinds of cutting tools dropping out while working and being lost :
In the accompanying drawing, Fig. 1 is a front view, Fig. 2 the same partly
in section, and Figs. 3 and 4 edge views illustrating the several parts of my
invention before being put together as shown in Figs. 5 and 6, which are respec-
tively front and edge views of the completed article. Figs. 7, 8 and 9 illustrate
a modification of my invention. In these views similar letters refer to similar
parts.
According to my invention I provide a small steel plug or plate of a convenient
shape or width to hold the diamond or stone and of a sufficient thickness to
contain the diamond or stone and leave a sufficiency of metal on all sides, say,
for example, about three quarters of an inch long by half an inch wide and
about three sixteenths to a quarter thick. I then file, cut away, or otherwise
reduce this thickness to about one half thereby forming a plate a having a flange
or shoulder b of the full thickness across one end as in Fig. 3.
I then drill a conical hole in a vertical direction through this flanged end
and also a like hole din a sloping direction beginning at the inner angle of the
flange or shoulder b and passing out at the outer angle or edge of the plate;
these holes are drilled with a slightly conical tool so that the external orifices
are smaller than the inner ends of the conical holes that are in the angle of the
flange and the plate a. I then place in each hole a diamond as c of a wedge
shape, formed to fit therein, and drive said diamond into the hole until the smaller
end of the diamond protrudes from the flange or at or near the end of the
plate a. I fit a plate e of a thickness corresponding to the projecting portion of
the flange band of the same width as the aforesaid flanged plate a, against the
butt end of the diamond or stone, and while it is firmly held in this position I
rivet the two plates together. By these means the diamonds or stones are
securely set, embedded, and retained in the steel plate or plug with their smaller
cutting ends protruding therefrom as shown in Figs. 5 and 6.
In a modification of my invention I employ two flat plates a¹ and e¹ as shown
in Figs. 7, 8 and 9, having conical slits or indents on the meeting surfaces of the
two plates into which the wedge or oval formed diamonds are inserted leaving
the cutting part projecting therefrom the two plates are then rivetted, clamped,
or brazed together thereby locking the diamonds securely in position.
The diamond holder with a diamond or diamonds as herein before described may
be dovetailed into or otherwise secured around the edges of a disc so as to form
a circular saw for cutting stone or hard substances, or may be fitted in a straight
bar so as to form a straight saw or in any tool for cutting or boring stone or the
like.

page_text: 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
claim is:-
1. The improved method of setting or fixing diamonds and like hard stones
in a holder that may be fitted in or attached to the edges of a disc so as to form
a circular saw or fitted to or in a straight bar to form a straight saw or fitted
in any tool for cutting or boring stone or other hard substances in the manner
and for the purpose substantially as herein before described.
2. An improved diamond holder as and for the purpose herein before described.
Dated this 28th day of August 1900.
GEO. DAVIES & SON,
Agents for the Applicant, 4, St. Ann's Square, Manchester.