IMPROVEMENTS IN EMERY WHEELS AND OTHER GRINDERS." SP
Year: 1880

page_text: LETTERS PATENT to John Pearson, of 25, Mortlock Gardens, Harders Road,
Pockham, in the County of Surrey, Commission Agent, James Whitestone, of
113, Queen Victoria Street, in tho City of London, Civil Engineer, &
Richard Russell Gubbins, of 17, Park Road, New Cross, in the County of
Kent, Civil Engineer, for an Invention of "IMPROVEMENTS IN EMERY WHEELS
AND OTHER GRINDERS."
PROVISIONAL SPECIFICATION left by the said John Pearson, James
Whitestone, and Richard Russell Gubbins at the Office of the Commissioners
of Patents on the 1st April 1880.
JOHN PEARSON, of 25, Mortlock Gardens, Harders Road, Peckham, in the County
of Surrey, Commission Agent, JAMES WHITESTONE, of 113, Queen Victoria Street,
in the City of London, Civil Engineer, & RICHARD RUSSELL GUBBINS, of 17,
"IMPROVEMENTS
Park Road, New Cross, in the County of Kent, Civil Engineer.
IN EMERY WHEELS AND OTHER GRINDERS."
Our Invention relates to solid emery wheels, grindstones, hones, and appliances
of the like sort formed of emery powder or sand in combination with a cementing
material, and consists in the composition of the cementing material and the
manner of using it, as hereinafter described. The cementing material is prepared
as follows:-Gluc is melted with a small quantity of water in the ordinary way,
and whilst hot a strong solution of tannic acid in methylated spirit is added, and
the mixture rapidly stirred for two or three ininutes. The cement thus formed is
then immediately poured upon the emery powder or sand, which has been
previously heated to a temperature of about 212° Fahrenheit, and the wholo
mass is then thoroughly incorporated by rapidly stirring it with iron forks. The
mixture is then transferred as rapidly as possible into a suitable iron mould (heated
to at least 212° Fahrenheit) and subjected to strong pressure by drawing together
the parts of the mould by screw bolts or other suitable means, and the mould is
then placed in an oven, maintained at a temperature of about 200° Fahrenheit,
where it is allowed to remain for about six hours, the necessary time varying with
the size of the article made. The article is then removed from the mould and
again baked in the oven for a further period of about six hours, after which it is
removed and allowed to cool.

page_text: The quantity of the liquids used in mixing the cement, that is to say, the
water added to the glue, and the methylated spirit, in which the tannic acid
is dissolved, should be as small as possible, having regard to convenience in mixing;
thus the glue or gelatine when melted should be somewhat less fluid than as
usually employed by joiners, and the tannic acid solution should be syrupy, a good!
proportion being thirty graames of tannic acid to one fluid ounce of spirit. In
making emery wheels we prefer to use the solid ingredients in the proportion of
twenty parts by weight of glue or gelatine to four parts of tannic acid and two
hundred and fifty parts of emery powder, all weighed dry, but the proportion of
cement to emery may be varied according to the special requirements of particular 1
cases.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said John Pearson, James Whitestone, and Richard Russell Gubbins in
the Great Seal Patent Office on the 1st October 1880.
JOHN PEARSON, of 25, Mortlock Gardens, Harder's Road, Peckham, in the County
of Surrey, Commission Agent, JAMES WHITESTONE, of 113, Queen Victoria Street,
in the City of London, Civil Engineer, and RICHARD RUSSELL GUBBINS, of 17,
Park Road, New Cross, in the County of Kent, Civil Engineer. "IMPROVEMENTS
IN EMERY WHEELS AND OTHER GRINDERS."
Our Invention relates to solid emery wheels, grindstones, hones, and appliances
of the like sort formed of emery powder or sand in combination with a cementing
material, and consists in the composition of the cementing material and the
manner of using it, as herein after described.
The cementing material is prepared as follows:-Glue is melted with a small
quantity of water in the ordinary way, and whilst hot a strong solution of tannic
acid in methylated spirit is added, and the mixture rapidly stirred for a few
minutes until it becomes thicker or more viscous. The cement thus formed and
whilst still hot is then poured upon the emery powder or sand, which has been
previously heated to a temperature of about two hundred and twelve degrees
Fahrenheit, and the whole mass is then-thoroughly incorporated by rapidly stirring
it with iron forks or by other suitable means. The mixture is then transferred as
rapidly as possible into a suitable iron mould (heated to about two hundred and
twelvo degrees Fahrenheit) and subjected to a strong pressure by drawing together
the parts of the mould by screw bolts or other suitable means, and the mould is
then placed in an oven maintained at a temperature of at least two hundred
and twelve degrees Fahrenheit, but not exceeding three hundred degrees Fahrenheit,
where it is allowed to remain until the mixture becomes hard. The time during
which the process of baking in the mould should be continued depends upon the
quantity and thickness of the mixture contained in the mould, that is to say, the
size and shape of the article made, so that it is necessary to bake large and thick
articles for a longer time than small and thin ones, but for an emery wheel twelvo
inches in diameter and one inch thick six hours are sufficient. The article is then
removed from the mould and again baked in the oven for about the same length of
time that it has been already baked in the mould.
The quantity of the liquids used in mixing the cement (that is to say, tho water
added to the glue, and the methylated spirit in which the tannic acid is dissolved)
should be as small as possible, having regard to convenience in mixing; thus the
glue or gelatine when melted should be somewhat less fluid than as usually
employed by joiners, and the tannic acid solution should be syrupy, a good
proportion being one ounce of tannic acid to one fluid ounce (one twentieth of a
pint) of spirit.
In making emery wheels we prefer to use the solid ingredients forming the
cementing material in the proportion of seventy seven parts by weight of glue or
gelatine to twenty three parts by weight of tannic acid, both weighed dry, which
quantities are sufficient for mixing as above described with about six hundred
parts by weight of emery powder, but the proportion of cement to emery may be
varied according to the requirements of particular cases.
The tannic acid solution may be made with water instead of methylated spirit,
but a larger quantity of liquid is in that case required, and a greater time is
required in baking to expel the moisture.
Tho materials used should be of very good commercial quality, although not
necessarily of absolute chemical purity.
After an emery wheel has been made as above described it is necessary that
the skin of cementing material shall be removed from its surface, which may

page_text: be best done by using a diamond tool, as usually employed for turning emery
wheels.
Although we have herein described the application of our Invention more
particularly to emery grinders particles of any hard matter may be used with the
cementing material, substantially as set forth.
In order to allow the articles to be removed the more easily from the moulds it
is desirable that the inner surfaces of the moulds shall be covered with some
non-adhesive substance, such as plumbago, to prevent the material from adhering
to the iron.
Having thus stated the nature of our said Invention, and particularly described
and ascertained the manner of performing the same, we declare that we claim as
our Invention, a cement for emery and other grinders, being a combination of glue
-or-gelatine-with taunic acid subiccted to heat and pressure after mixture with the
be best done by using a diamond tool, as usually employed for turning emery
wheels.
Although we have herein described the application of our Invention more
particularly to emery grinders particles of any hard matter may be used with the
cementing material, substantially as set forth.
In order to allow the articles to be removed the more casily from the moulds it
is desirable that the inner surfaces of the moulds shall be covered with some
non-adhesive substance, such as plumbago, to prevent the material from adhering
to the iron.
Having thus stated the nature of our said Invention, and particularly described
and ascertained the manner of performing the same, we declare that we claim as
our Invention, a cement for emery and other grinders, being a combination of glue
-or-gelatine-with taunic acid subiccted to heat and pressure after mixture with the
emery powder or sand, as herein set forth.
In witness whereof, I, the said Richard Russell Gubbins, for myself and on
behalf of the said John Pearson and James Whitestone, have hereunto set
my hand and seal, this First day of October, in the year of our Lord One
thousand eight hundred and eighty.
R. R. GUBBINS. (L.S.)