IMPROVEMENTS IN THE TREATMENT OR PREPARATION OF MOULDS FOR CASTING METALS
Year: 1858

page_text: LETTERS PATENT to Andrew Walker, of Shotts, in the County of Lanark,
N.B., Moulder, and Thomas Walker, of the same Place, Pattern Maker,
for th Invention of "IMPROVEMENTS IN THE TREATMENT OR PREPARATION
OF MOULDS FOR CASTING METALS."
Sealed the 13th July 1858, and dated the 19th January 1858.
PROVISIONAL SPECIFICATION left by the said Andrew Walker and
Thomas Walker at the Office of the Commissioners of Patents, with
their Petition, on the 19th January 1858.
We, ANDREW WALKER, of Shotts, in the County of Lanark, N.B., Moulder,
and THOMAS WALKER, of the same Place, Pattern Maker, do hereby declare
the nature of the said Invention for "IMPROVEMENTS IN THE TREATMENT OR
PREPARATION OF MOULDS FOR CASTING METALS," to be as follows:-
This Invention relates to the treatment or preparation of the surfaces of
sand moulds for casting metals by means of anthracite, "blind," or "stone"
coal dust. The coal or mineral preferred for this purpose is anthracite, but
any coal of an anti-bituminous kind will answer for carrying out the improve-
ments. The coal or anthracite mineral is used in its natural condition as dug
from the earth, being merely reduced by mechanical means to the proper
condition of powder or dust. The powder or dust is placed in permeable bags
and dusted upon the mould surfaces with which the metal will come in contact
when the casting operation takes place. The same material may also be used-

page_text: as a wash for moulds; it may also be employed mixed with sand, as in the
case of common coal dust. This system of preparing mould surfaces secures
economy in the materials used, whilst it also enables the founder to produce
extremely sharp and fine castings.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Andrew Walker and Thomas Walker in the Great Seal
Patent Office on the 19th July 1858.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, ANDREW
WALKER, of Shotts, in the County of Lanark, North Britain, Moulder, and
THOMAS WALKER, of the same Place, Pattern Maker, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Nineteenth day of January, in the year of our
Lord One thousand eight hundred and fifty-eight, in the twenty-first year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto us,
the said Andrew Walker and Thomas Walker, Her special license that we,
the said Andrew Walker and Thomas Walker, our executors, administrators,
and assigns, or such others as we, the said Andrew Walker and Thomas
Walker, our executors, administrators, or assigns, should at any time agree
with, and no others, from time to time and at all times thereafter during
the term therein expressed, should and lawfully might make, use, exercise,
and vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN THE
TREATMENT OR PREPARATION OF MOULDS FOR CASTING METALS," upon the con-
dition (amongst others) that we, the said Andrew Walker and Thomas
Walker, by an instrument in writing under our hands and seals, should
particularly describe and ascertain the nature of the said Invention, and in
what manner the same was to be performed, and cause the same to be filed
in the Great Seal Patent Office within six calendar months next and imme-
diately after the date of the said Letters Patent.
NOW KNOW YE, that we, the said Andrew Walker and Thomas Walker,
do bereby declare the nature of our said Invention, and in what manner
the same is to be performed, to be particularly described and ascertained in
and by the following statement, that is to say:-
"
Our said Invention relates to the treatment or preparation of the surfaces of
sand moulds for casting metals by means of anthracite, "blind," or "stone"
coal dust. The coal or mineral preferred for this purpose is anthracite, but

page_text: any coal of an anti-bituminous kind will answer for carrying out the improve-
ments. The coal or anthracite mineral is used in its natural condition as dug
from the earth, being merely reduced by mechanical means to the proper
condition of powder or dust. The powder or dust is placed in permeable bags
and dusted upon the mould surfaces with which the metal will come in contact
when the casting operation takes place. The same material may also be used
as a wash for moulds; it may also be employed mixed with sand, as in the
case of common coal dust. This system of preparing mould surfaces secures
economy in the materials used, whilst it also enables the founder to produce
extremely sharp and fine castings.
And in order that our said Invention may be properly understood, we shall
now proceed to describe the same in detail, and to explain certain modifi-
cations under which our improvements may be judiciously carried out in
practice. In preparing moulds according to the ordinary manner, it is the
practice to dust the surface of the mould over with charcoal, finely powdered,
which is distributed over the moulding sand by shaking it through the inter-
stices of a linen bag. In other cases the charcoal dust is mingled with water,
and the compound is used as a wash for coating the surfaces of moulds for
casting metals. We have found in practice that by using other kinds of,
carbonaceous matters for coating, dusting, or washing the surfaces of sand
moulds, that the castings resulting therefrom are much superior in point of
sharpness over those treated in the ordinary manner. The carbonaceous:
material we prefer to use for the purpose is anthracite, "blind," or "stone"
coal, that is to say, a coal of an anti-bituminous nature, or comparatively un-
inflammable kind. Anthracite is, however, the material to which we give the
preference; this mineral is used in its ordinary or natural state. A quantity
of this mineral is taken and reduced to a fine powder, either by grinding it in
a mill or pulverizing it under edge runners, or otherwise reducing it by
mechanical means to a finely divided state. This powder or anthracite coal:
dust is then placed in bags of linen cloth or other permeable material through
which the minute particles can readily pass. After the sand mould is prepared
in the ordinary manner the surfaces imprinted by the pattern or patterns
are dusted over with the pulverized anthracite or other anti-bituminous car-
bonaceous material. The pulverized anthracite may also be applied in the form
of a wash by mixing it with water to the consistency of cream; this mixture is
laid upon the surfaces of the mould by means of a brush, in the same manner
as the charcoal wash is applied. The powdered anthracite or other anti-
bituminous material may also be mixed with sand and used in the same manner
as the unmixed moulding material. This mixture may be advantageously

page_text: used for making the moulds for various articles, and does not require any
coating upon the surface of the moulds.
Having now described and particularly ascertained the nature of our said
Invention, and the manner in which the same is or may be used or carried
into effect, we may observe, in conclusion, that we do not confine or restrict
ourselves to the precise details or arrangements which we have had occasion
to describe or refer to, as many variations may be made therefrom without
deviating from the principles or main features of our Invention; but what we
consider to be novel and original, and therefore claim as the Invention secured
to us by the herein-before in part recited Letters Patent, is,-
First, the system or mode of treating and preparing moulds or cores for
casting metals, as herein-before described.
Second, the use and application of anthracite or other anti-bituminous
material to the purpose of dusting the surface or surfaces of moulds or cores for
casting metals, as herein-before described.
Third, the system or mode of coating the surface or surfaces of moulds or
cores with a liquid composition or wash, composed of anthracite or other anti-
bituminous material reduced to powder and mingled with water, as herein-before
described.
Fourth, the use and application of pulverized anthracite or other non-
bituminous material mixed with sand to the purpose of making or forming
moulds or cores for casting metals, as herein-before described.
In witness whereof, we, the said Andrew Walker and Thomas Walker,
have hereunto set out hands and seals, this Fifteenth day of July, One
thousand eight hundred and fifty-eight.
ANDREW WALKER. (L.s.)
THOMAS WALKER.
(L.S.)
ANDREW WALKER. (L.S.)
THOMAS WALKER.
(L.S.)