Grinding, Sharpening, and Polishing.
Year: 1887

page_text: Date of Application, 14th Dec., 1887
Complete Specification Left, 14th Sept., 1888
Complete Specification Accepted, 2nd Nov., 1888
Grinding, Sharpening, and Polishing.
I, EDWARD DUNNING BARKER, of 115 Cannon Stroet, in the City of London,
Engineer do herchy declare the nature of this invention to be as follows:-
My invention relates more especially to the manufacture of wheels and other tools
for grinding, sharpening and polishing, the cutting particles of which are composed of
emery, corundum, and such like, but it is also applicable to the manufacture of such
wheels or tools, the cutting particles of which are composed of certain other substances.
The object of my invention is to produce a grinding sharpening or polishing wheel or
tool in which the cutting particles are held together more firmly than heretofore,
whereby a very strong and lasting wheel or tool is produced.
For this purpose I proceed as follows:-
I take powdered German, or other suitable soft, and easily fused, glass, and
thoroughly mix therewith a proportion of metallic oxide such as oxide of lead
(litharge for example) or, in some cases, borax. This mixture is intended to form
the cement for uniting together the particles of emery or other cutting material.
I then moisten the emery or other cutting material with sufficient water to damp the
entire surface of every particle, and I add to such moistened cutting material a proper
proportion of the above described cementing mixture, and thoroughly mix or in-
corporate the whole together. I next ram a suitable quantity of this mixture into a
metallic or other fire resisting mould of the shape and dimensions the wheel or tool is
intended to have, and place the said mould, with its contents, in a furnace raised to a
sufficient heat to fuse the cementing material. When this is accomplished, I with-
draw the mould and its contents froin the furnace more or less gradually, or place
them in an annealing oven to enable the wheel or tool to cool slowly, whereby risk of
breakage by sudden contraction is avoided. When sufficiently cool, the wheel or
other tool is removed from the mould and is ready for use.
By the use of the above process and materials, I am enabled to produce an

page_text: 22
extremely strong wheel or tool, and one which will do more work, for a given
expenditure of wheel or tool, than either the ordinary "silicate" or "black"
wheel.
When the mould is made of metal, (wrought iron for example) it is liable to
contract in cooling more than the wheel or tool which has been fused in it and
such wheel or tool is sometimes injured thereby. I therefore prefer to make the
mould with a joint at one or both sides in such manner that by slacking back a
screw, driving out a key or wedge, or some such device, while the mould and its
contents are still hot, the mould is left free to contract without exerting an injurious
pressure upon the wheel or tool contained therein.
Dated this 13th day of December 1887.
E. D. BARKER.
Per W. H. Beck,
115, Cannon Street, London, E.C.,
Agent.

page_text: Improvements in the Manufacture of Wheels and other Tools for
Grinding, Sharpening, and Polishing.
1, EDWARD DUNNING BARKER, of 115 Cannon Street, in the City of London,
Engineer 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, reference being had to the accompanying sheet of Drawings,
and to the letters and figures marked thereon, that is to say:-
My invention relates more especially to the manufacture of wheels and other tools
for grinding, sharpening, and polishing, the cutting particles of which are composed
of emery, corundum and such like but it is also applicable to the manufacture of
such wheels or tools the cutting particles of which are composed of certain other
substances such as sand or hard glass for example. The object of my invention is to
produce a grinding, sharpening or polishing wheel or tool in which the cutting
particles are held together more firmly than heretofore whereby a very strong and
lasting wheel or tool is produced.
For this purpose I proceed as follows:-
--
I take powdered German or other suitable soft, and easily fused glass, and in some
cases thoroughly mix therewith a proportion of a metallic oxide which possesses the
property of reducing the fusing point of glass, such as oxide of lead (litharge for
example) or, in some cases I employ borax instead of metallic oxide. This glass or
mixture of glass and metallic oxide or of glass and borax is intended to form the
cement for uniting together the particles of emery or other cutting material. I then
moisten the emery or other cutting material with sufficient water to damp the entire
surface of every particle thereof and I add to such moistened cutting material a proper
proportion of the above described cementing material and thoroughly mix or
incorporate the whole together. I next ram a suitable quantity of this mixture of
cutting and cementing materials into a metallic or other suitable fire resisting mould
of the shape and dimensions the wheel or tool is intended to have, preferably
compressing the said mixture in the mould by hydraulic or other suitable pressure, I
then clamp the said mould between strong plates as hereinafter more fully described
and illustrated in the Drawings, and place the said mould, with its contents and
clamping plates, in a furnace raised to a sufficient heat to fuse the cementing material.
When this is accomplished I withdraw the mould and its contents from the furnace
more or less gradually or place them in an annealing oven to enable the wheel or too!
to cool slowly, whereby risk of breakage by sudden contraction is avoided. When
sufficiently cool the wheel or other tool is removed from the mould, and after being
trued up in the usual way, when necessary, is ready for use.
The proportions of the abovementioned ingredients vary according to the kind of
wheel or tool it is required to produce, and the coarseness or fineness of the cutting
material employed; for example I have obtained good results by mixing, 62 ounces
of powdered emery of from No. 16 to No. 24 gauge, with 10 ounces of powdered

page_text: German glass and 12 ounces of litharge, and by mixing 60 ounces of powdered emery
of from No. 60 to No. 80 gauge, with 20 ounces of powdered German glass and
20 ounces of litharge; also by mixing 62 ounces of powdered emery of from No. 24
to No. 36 gauge with 12 ounces of powdered German glass and 6 ounces of powdered
borax.
Instead of employing powdered glass as above described powdered materials from
which such glass is produced may be mixed with the powdered cutting material, and
the metallic oxide or borax ; but I prefer to use glass previously manufactured and
reduced to powder.
The above described process of fusing the vitreous cementing materials while
still in the mould is obviously applicable to the fusing of any kind of vitreous
cementing materials besides those above described provided the fusing temperature of
such materials is not high enough to injure the moulds.
By the use of the above process and materials I am enabled to produce an
extremely strong wheel or tool and one which will do more work for a givon
expenditure of wheel or tool than either the ordinary "silicate" Ol' "black
wheel.
When the mould is made of metal (wrought iron for example) it is liable to
contract in cooling more than the wheel or tool which has been fused in it, and such
wheel or tool is sometimes injured thereby. In order to obviate this I make the
mould with a joint at one side, as illustrated in the Drawing hereto annexed, and in
order to prevent the material in the mould from swelling up or expanding which
sometimes takes place during the fusing operation and whereby the wheel or tool is
rendered unduly porous, I clamp the mould between strong plates, as also illustrated
in the Drawing.
Figure 1 is a plan of a mould suitable for making grinding, sharpening, or
polishing wheels in accordance with my invention but with the above mentioned
clamping plates removed, Figure 2 is a section of same on line X X of Figure 1 with
the clamping plates in position, and Figure 3 is an elevation taken at the joint side of
the mould.
A is the body of the mould formed of a bar of wrought iron for example bent to
the form the wheel or tool is intended to have, and shaped with two lugs A¹ over
which is passed a keeper ring B to prevent the mould from opening while the material
is being rammed or pressed into it, and while the mould and its contents are in the
furnace. When the cementing material is sufficiently fused, the ring B is knocked off,
and the mould A is then free to contract in cooling, independently of the wheel or
tool C contained in it.
DD are the plates abovementioned, between which the mould A is clamped by
means of the bolt E passing through central holes in the said plates and in the
wheel C, the plates D being forced against the mould by the key F driven through
a slot in the end of the bolt E or if preferred by means of a nut screwed on to the
end of the said bolt. In cases where a central bolt E cannot be employed the plates D
may be made to project beyond the mould A and any required number of bolts,
similar to the bolt E for example, may be passed through holes in the projecting parts
outside the mould in order to clamp the latter between the plates.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I desire to have it
understood that I am aware that it is not novel to construct grinding, sharpening or
polishing wheels or tools, by mixing moistened powdered cutting material with
powdered glass, borax, or other vitreous substance with or without litharge, moulding
the mixture in moulds, and then submitting the moulded articles to heat after they
have been removed from the moulds, and I make no claim generally to such process
or method of construction, but I declare that what I do claim is :-
First The process of manufacturing wheels and tools for grinding, sharpening,
and polishing, which consists in mixing moistened powdered-cutting materials with
the powdered vitreous cementing materials described with or without the addition

page_text: of a metallic oxide which facilitates the fusion of the vitreous material, in ramming or
pressing the mixture into fire-resisting moulds, and in submitting such mixture, while
still in the said moulds, to a temperature sufficient to fuse the said vitreous cementing
materials, substantially as hereinbefore described.
Second In the manufacture of wheels and other tools, for grinding, sharpening,
and polishing, composed of powdered cutting materials-cemented together by means
of vitreous materials, effecting the fusion of the said vitreous cementing materials
while the mixture of cutting and cementing materials is in the mould, substantially as
herein before described.
Third In the manufacture of wheels and other tools, for grinding, sharpening, and
polishing, composed of powdered cutting materials cemented together by means of
vitreous materials, effecting the fusion of the said vitreous cementing materials while
the mixture of cutting and cementing materials is in the mould, and confined therein
so as to be prevented from swelling up or expanding during the fusing process,
substantially as herein before described.