Improved Method of Setting Diamonds in Cutting Tools and the like and Apparatus for same.
Year: 1893

page_text: COMPLETE SPECIFICATION.
Improved Method of Setting Diamonds in Cutting Tools and the
like, and Apparatus for same.
I, ALBERT HEINRICH DITTMER, of 37 Havelbergerstrasse, Berlin, Technologist,
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 in stone cutting
tools saws and the like and to apparatus which may he employed in carrying out
such setting, the object being to hold the diamonds in their setting in a ductile or a
casting metal in such a manner that the position selected is not altered during the
process of setting same as is frequently the case with the soldering processes at
present employed where it is difficult to prevent the stone altering its position during
setting so that the chosen cutting edge of same is not in the desired position when
the settling is completed.
According to the present invention a method is provided by which reliable results
may be secured either where the setting takes place by forging or in a casting
mould as will be hereafter described.
In the annexed drawing
Figures 1 to 7 illustrate various stages of the method of setting diamonds in such
ductile metals as iron, steel, bronze &c.
In the top of the bar or piece of metal, a is made a hole a little larger than the
diamond to be set so that the latter can be turned about in it to secure the
desired position which may be that shown in Figure 1.
To ensure the diamond remaining in this position a small cone of some plastic
material such as moulding sand loam clay or the like is placed point downwards on
the diamond as shewn in Figure 2 this form being employed so that the position of
the diamond may be observed up to the filling in of the hole which takes place by
That side of the bar a
pressing down the said loam or clay as shewn in Figure 3.
towards which the operative edge of the diamond is directed is now marked in a
suitable manner (as by a chalked line) and the metal bar is laid with the end
containing the diamond in a forge fire and so far heated that the metal becomes
thoroughly malleable and capable of being forged. When the bar is withdrawn
the edges of the hole are hammered together as shown in Figure 4 the blows being
directed on those sides towards which the operative edge of the diamond is not
turned so that no shifting of the stone will take place.
The loam or the like which has protected the diamond from the direct action of
the fire is by this hammering knocked out in powder and the bar is then worked
upon by hammer blows directed upon its head (Figure 5) to enclose the diamond
and is further worked upon from the sides (Figure 6) to complete the enclosing.
As the manner in which the stone is lying in the bar is known all that now remains
to be done is to lay bare the operative edge by filing away the surrounding metal so
that the bar will present somewhat the appearance shown in Figure 7.
This method of fastening serves for the production of teeth for diamond saws and
like tools the set diamond being cut away from the bar together with the necessary
amount of metal so that the so called discs are produced, such discs being usually
adjusted in rectangular spaces on the edge of a saw or other tool.
In some cases to ensure the better holding of these pieces of metal bearing the
diamond in the tool it is desirable to cut out the spaces of the latter so as to prevent
the piece falling out even with the hardest usage of the tool.
Figures 8 and 9 show a top and edge view respectively of a piece of a blade of a
saw with various notches v formed in this way.
Figures 10 and 11 are a top and edge view respectively of a piece of a tool w¹ for

page_text: cutting stones in which the diamond is placed in a curved piece so that it may be
used for certain special purposes.
Figures 12 and 13 are respectively a section and side view of a curved blade 10
with a diamond tooth.
In all these cases a method of casting for securing the diamond also recommends
itself, the operation being carried out in such a manner that the tool itself forms one
part of the casting mould the other part being formed by an adjustable mould
hereafter described. The set diamond when the casting in of same is completed
only requires the laying bare of the cutting edge by the removal of the superfluous
metal from the sides and top.
The mould or apparatus for the above purpose is illustrated in Figure 14 in plan
and in Figure 15 in sectional elevation.
It consist of a block of metal e the front of which is cut away to leave the piece d
in which is set a small pin e. On the upper surface of the block c is a curved
spring held by means of screws i provided with thumb nuts, slots in the spring
providing for longitudinal adjustment.
с
The front part g of the spring is bent down as shown and presses upon the
diamond which is supported upon the pin e the cutting edge being first placed in
the position desired. The part d forms the bottom of the mould and the gap or
space in the tool or bar w which is to receive the diamond forms a part of the three
sides of same, a fourth side being formed by the shoulder of the block e where it is
cut away.
Where the diamond is to be arranged on the edge of the tool w as shown
a cut away piece y is placed above the tool w and a similar piece is placed below
same. To complete the closing of the mould as the tool w cannot be brought
up to the shoulder of the block c, metal bars m are secured to the sides of the
block by means of the screws n n the bars being provided with slots o so that they
may be moved up to the tool w or otherwise adjusted.
2
After the pouring in of the fluid metal into the mould formed as above the front
screw i is loosened so that the spring f rises up from the metal which closes up the
opening so formed and upon cooling prevents any change in the position of the diamond.
The removal of the tool with the set diamond from the pin e presents no difficulty
and the hole left by the latter is of small moment as it is usually in the part of the
frame or setting which has to be cut away to turn the operative edge of the diamond
to account. A similar method of setting may be employed in which the mould for
casting is not formed partly by the tool itself as above described in which case the
mould is formed by a suitable frame or frames the diamond being held as above
described. By this method discs of metal enclosing a diamond are produced such
discs being suitable for use in the production of tools for various purposes.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. The improved method of setting diamonds in cutting tools consisting in placing
the diamond in a hole or socket in the tool, heating the latter and closing the metal
of the tool around the diamond by forging, the position of the diamond being
maintained during a part of the operation by placing a suitable plastic substance in
the socket substantially as described.
2. The improved method of setting diamonds in cutting tools consisting in holding
the diamond in a mould between a spring and a pin and casting the metal around
same substantially as described.
3. The apparatus employed in the setting diamonds by casting consisting of the
block e having a shoulder and a cut away part d, a pine spring and adjustable
side bars m substantially as described.
1
.
PHILIP M. JUSTICE,
55 & 56, Chancery Lane, London, Chartered Patent Agent.