IMPROVEMENTS IN THE PREPARATION OF MOULDS FOR CASTING METALS
Year: 1873

page_text: LETTERS PATENT to James Mackintire, of Cambridge, in the State
of Massachusetts, in the United States of America, but at present
residing at Villiers Strect, Strand, in the County of Middlesex, for
thic Invention of "IMPROVEMENTS IN THE PREPARATION OF MOULDS FOR
CASTING METALS."
Sealed the 20th February 1874, and dated the 31st December 1873.
PROVISIONAL SPECIFICATION left by the said James Macintire at the
Office of the Commissioners of Patents, with his Petition, on the
31st December 1873.
I, JAMES MACKINTIRE, of Cambridge, in the State of Massachusetts,
in the United States of America, but at present residing at Villiers
Street, Strand, in the County of Middlesex, do hereby declare the nature
of the said Invention for "IMPROVEMENTS IN THE PREPARATION OF MOULDS
FOR CASTING METALS," to be as follows:-
:―
The Invention relates to improvements in the preparation of moulds
for casting metals, which moulds may be "fired" or baked in a similar
manner to pottery ware, or they may be used without being fired or

page_text: baked, and has for its object the production of a finer surface or face to
the moulds than heretofore, whilst such improved moulds are better
capable of withstanding the heat of the furnace during the "baking” or
firing process, and when used for casting deliver the castings much more
freely than those at present in use. For this purpose I prepare the
moulds in the following manner:-I take about one part by weight of
fine pulverized loam or clay loam sufficiently dry, and grind it to a
powder, and I mix this with about two parts by weight of kaolin or
china clay. I also dissolve about one ounce of gelatine in one gallon of
water, and to this I add about one quart of glycerine and a small
quantity of carbolic acid, ammonia, or other preservative agent to keep
the mixture from becoming mouldy. I use sufficient of this latter pre-
paration to make the mixture of clay, loam, or loam and kaolin to a
thick paste or "slip," and this latter can be kept any length of time
ready for use.
In making the paste or "slip," the clay, loam, or loam and kaolin or
china clay should be first sifted together through a fine sieve to remove
any foreign substance therefrom and to more evenly mix them together.
I then add thereto the aforesaid liquid preparation, and by preference
allow the mixture to stand a few days, after which I pass it through a
very fine wire or gauze sieve in order that all clots or lumps may.
be removed therefrom, after which it is ready for use.
In preparing a mould for casting, I dilute the thick paste with water
so as to bring it to a suitable consistency for "slipping" the patterns
for moulding, that is to say, for applying a thin coating to the pattern.
After "slipping" the pattern I next place it in the mould box and fill
the latter with a sufficient quantity of loam or clay and sand to produce
the mould. I then apply such an amount of pressure as will suffice to
level the mould. I next remove the pressure from the mould and
thoroughly dust over the top thereof with kaolin or china clay for the
purpose of securing a smooth and non-adhesive surface for the protection
of the back of an adjacent casting from the more adhesive substance of
which the body of the mould is composed. I then apply sufficient
pressure to the mould to finish it and produce a fine surface finish
thereto, after which the moulds can be handled like a brick.
In preparing the clay or loam for the body of the mould, it is first
dried and ground, and then when required for use it is moistened
sufficiently to enable it to adhere together.

page_text: "
By these means I can produce a mould with a perfectly smooth,
sharp, and sound surface, which will "fire or "bake" without cracking,
and which, when used for casting, will freely deliver the castings there-
from.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said James Macintire in the Great Seal Patent Office
on the 30th Junc 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
MACINTIRE, of Cambridge, in the State of Massachusetts, in the United
States of America, but at present residing at Villiers Street, Strand, in
the County of Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Thirty-first day of December, in the
year of our Lord One thousand eight hundred and seventy-three, in the
thirty-seventh year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said James Mackintire, Her special
license that I, the said James Mackintire, my executors, administrators,
and assigns, or such others as I, the said James Mackintire, my executors,
administrators, and 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
send, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
THE PREPARATION OF MOULDS FOR CASTING METALS," upon the condition
(amongst others) that I, the said James Mackintire, my executors or
administrators, by an instrument in writing under my, or their, or one
of their 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 immediately after the date
of the said Letters Patent.
NOW KNOW VE that I. the said James Mackintire. do hereby declare

page_text: "
performed, to be particularly described and ascertained in and by the
following statement thereof, that is to say :-
The Invention relates to improvements in the preparation of moulds
for casting metals, which moulds may be "fired" or baked in a similar
"fired" or
manner to pottery ware, or they may be used without being
baked, and has for its object the production of a finer surface or face to
the moulds than heretofore, whilst such improved moulds are better
capable of withstanding the heat of the furnace during the "baking" or
'firing" process, and when used for casting deliver the castings much
more freely than those at present in use. For this purpose I prepare
the moulds in the following manner:-I take about one part by weight
of fine pulverized loam, or clay loam sufficiently dry, and grind it to a
powder, and I mix this with about two parts by weight of kaolin or
China clay. I also dissolve about one ounce of gelatine, glue, isinglass,
or other analogous gummy matter in one gallon of water, and to this I
add about one pint of glycerino, and a small quantity of carbolic acid,
ammonia, or other preservative agent to keep the mixture from becoming
mouldy. I use sufficient of this latter preparation to make the mixture
of clay loam or loam and kaolin to a thick paste or "slip," and this
latter can be kept any length of time ready for use.
In making the paste or "slip," the clay loam or loam and kaolin or
China clay should be first sifted together through a fine sieve to remove
any foreign substance therefrom and to more evenly mix them together;
I then add thereto the aforesaid liquid preparation, and by preference
allow the mixture to stand a few days, after which I pass it through a
very fine wire or gauze sieve, in order that all clots or lumps may be
removed therefrom, after which it is ready for use.
In preparing a mould for casting I dilute the thick paste with water,
so as to bring it to a suitable consistency for "slipping" the patterns for
moulding, that is to say, for applying a thin coating to the pattern. After
"slipping" the pattern I next place it in the mould box, and fill the
latter with a sufficient quantity of loam or clay and sand to produce the
mould. I then apply such an amount of pressure as will suffice to level
the mould. I next remove the pressure from the mould, and thoroughly
dust over the top thereof with kaolin or China clay, for the purpose of
securing a smooth and non-adhesive surface for the protection of the
back of an adjacent casting, from the more adhesive substance of which