OR IMPROVED METHODS, PROCESSES, AND APPARATUS FOR DEPOSITING UPON WROUGHT IRON, STEEL, AND CAST IRON LAYERS OF COPPER OR ALLOYS OF COPPER
Year: 1872

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn Fields,
in the County of Middlesex, Gentleman, for the Invention of
"NEW OR IMPROVED METHODS, PROCESSES, AND APPARATUS FOR DEPOSITING
UPON WROUGHT IRON, STEEL, AND CAST IRON LAYERS OF COPPER OR ALLOYS
OF COPPER." -A communication from abroad by Octave Gauduin,
Chemist, Jean Baptiste Java Mignon and Stanislas Henry Rouart,
Builders, all of Paris, in the Republic of France.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson
at the Office of the Commissioners of Patents, with his Petition, on
the 31st December 1872.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County
5 of Middlesex, Gentleman, do hereby declare the nature of the said
Invention for "NEW OR IMPROVED METHODS, PROCESSES, AND APPARATUS FOR
DEPOSITING UPON WROUGHT IRON, STEEL, AND CAST IRON LAYERS OF COPPER OR
ALLOYS OF COPPER," a communication to me from abroad by Octave
i

page_text: Gauduin, Chemist, Jean Baptisto Java Mignon and Stanislas Henry
Rouart, Builders, all of Paris, in the Republic of France, to be as
follows:-
Many unsuccessful attempts have been already made to copper
wrought iron, stecl, or cast iron, but the coating of copper was never
sufficiently adherent, and by want of thickness or of homogeneity was
speedily destroyed. With these processes it is easy to cover wrought
iron, steel, and cast iron with a coating of copper, of gun metal, of
yellow copper, of aluminium bronze, or other similar alloys, the said
coating being adherent, homogeneous, and as thick as may be desired.
Dry or humid processes are used according to the nature or thickness
of metal to be deposited, or in order to make the work easier.
1. First Dry Process.-For the depositing of a thick coating of copper,
gun metal, yellow copper, or other metals on wrought iron, steel, or
cast iron. When it is not necessary to have the said coating perfectly
regular, that is, for covering printing cylinders, chairs, large cocks, and
similar articles, I melt in a crucible of a form suited to the piece to be
coated the quantity of metal necessary for the deposit, and I cover the
surface of the melted metal with a thickness of a flux composed of a
mixture of double fluor of aluminium and sodium (cryolite) with phos-
phoric acid. I dip in the bath the piece to be coated which has been
first heated to the degree of the melted metal which must cover all the
surface to be coated. All that is necessary is to let cool in order to
avoid blisters.
For the coppering of wrought iron borax may be used, but for cast
iron or steel it is necessary to employ the aforesaid flux because borax
does not scour cast iron or steel.
To make the work easier the following arrangement may be used:--
The metal to be deposited, copper, gun metal, or yellow metal, is melted
in a crucible of natural or agglomerated carbon, having the form of a
semi-cylindrical trough, the flux being lighter remains on the surface of
the melted metal to avoid the oxidation and to scour the surfaces to be
coated. The wrought or cast-iron cylinder supported on its axle has
only a part of its circumference in the melted metal. When a sufficient
heat is obtained by giving a rotatory motion to the cylinder all the
surface comes in contact with the metal to be deposited, and the rotatory
motion is continued till a sufficient thickness is obtained.

page_text: 2. Second Dry Process With or Without an Electric Current.-Such
process is used for depositing a light coat of copper on manufactured
goods. A mixture of one part of dry chloride or fluoride of copper and
five or six parts of cryolite, to which may be added a certain quantity
of chloride of baryum to render it more fusible, is melted in a crucible
or an oven made of carbon. Such proportions may vary in great limits.
When the mixture is well melted the wrought iron, steel, or cast iron
goods to be coppered and scoured at first are dipped in the mixture, and
acting by way of affinity remove the copper from its combination, and
are covered with an adherent coat more or less thick, according to the
delay of immersion and of concentration of the bath. The use of an
electric current having the negative pole in contact with the goods to be
coppered, and the positive pole with an ingot of copper immersed in the
bath, offers the advantage of keeping the mixture constant and making
the deposit easier. A crucible of copper which may make part of the
circuit may also be used.
Other salts of copper mixed or not with cryolite or with other alkaline
salts or earthy alkaline salts may give the same results, but the Inventors
claim as their Invention the idea of decomposing the melted simple
salts of copper, or combined with other salts by way of affinity or by
electric decomposition.
3. Humid Process.-Many copper salts, alkaline or neutral mixed
with water have been tried without success to deposit on wrought iron,
cast iron, or stecl a coat of copper thick, adherent, and continuous. The
scouring of wrought and cast iron is never perfect, and the bath used
could not complete the said scouring.
It has been observed that for coppering wrought iron, steel, or cast
iron it is necessary to work in a very acid solution able to dissolve the
oxides of iron remaining after the scouring without however attacking
the metal itself. Such a solution acts continually by its scouring pro-
perties on the places where the copper is not yet deposited, and dissolves
the oxides which prevented the deposit. Besides the acidity of the
solution greatly improves the physical properties of the deposit, which
becomes adherent, malleable, and ductile, and by its great conductibility
lessens the expense of electricity.
Many organic acids, and especially the organic polibasies, tartaric,
oxalic, succinic, citric, malic, and other acids having similar properties,

page_text: combined with oxides of copper and other alkaline oxides in the state of
double acid salts as in the bi-tartrates, bi-oxalates, quadr-oxalates, bi-
succinates, bi-citrates, bi-malates, alkaline combined with correspondent
copper salts and excess of acid when they do not attack too deeply
the iron are more or less able to give a good deposit. So the oxalates of
copper combined with a very great excess of bi- or quadr-oxalates of
sodium with excess of acid, and dissolved in ten or fifteen times their
weight of water, give a very good deposit on wrought iron, cast iron, or
steel. 60 to 90 degrees centigrade of heat will make the work easier.
When a great thickness of copper is required the use of an electric
current becomes necessary. For scouring the metals and for using the
electricity the ordinary methods are employed. For depositing on
wrought iron, cast iron, or steel alloys of copper and zinc, copper and
tin, copper and aluminium, it is sufficient to mix with the baths of
copper above described a similar bath of zinc, tin, or aluminium in
quantity inversly proportional to the electric conductibility of the two
baths, and to operate with soluble anodes made of yellow copper, gun
metal, aluminium bronze. The same results may be obtained by working
for a short time in a bath of copper with a soluble anode made of yellow
copper, gun metal, or aluminium bronze, or rather of zinc, tin, or
aluminium, taking care to well proportionate the tension of the electric
current to the surface to be covered. This condition is essential to the
success of the operation, because a weak current affects only the salt of
copper, while a strong current rather affects the zinc, the tin, or the
aluminium.
The coppering of wrought iron, cast iron, or steel by these processes
may be used as an intermediate between those bodies and lead, when it
is necessary to cover them entirely or partially with a very solid sheet of
lead, as is the case for covering projectiles.. Such coverings of lead arc
made now by the intermediary of zinc.
The projectile is coppered by one of these processes when this first
result is obtained. The projectile is heated to 200 or 300 degrees centi-
grade, and scoured in a solution of chloride of zinc, and dipped in a bath
of melted lead to a degree a little above its point of fusion. When a
great thickness is wanted a mould may be used, and the lead is cast in
the space between the mould and the projectile.
In short the Inventors intend to Patent different processes and
apparatus for depositing on wrought iron, steel, or cast iron coats or

page_text: seams more or less thick, but adherent and continuous, of copper and
alloys of copper.
The said process may be summed up as follows:—
1st. A dry process and the necessary apparatus peculiarly applicable
for depositing thick scams of metal as on printing cylinders, machine
chairs, and other like articles.
2nd. A dry process of precipitation, with or without using electricity,
based on the decomposition of simple or compound salts of copper kept
in fusion.
3rd. A humid process of precipitation of copper and of its alloys,
|with or without using electricity as above described.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Henry Johnson in the Great Seal Patent
Office on the 27th June 1873.
•
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
Gentleman, 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-two, in the
36th year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said John Henry Johnson, Her special license
that I, the said John Henry Johnson, my executors, administrators,
and assigns, or such others as I, the said John Henry Johnson,
my 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 "NEW OR IMPROVED
METHODS, PROCESSES, AND APPARATUS FOR DEPOSITING UPON WROUGHT IRON, STEEL,
AND CAST IRON LAYERS OF COPPER OR ALLOYS OF COPPER," a communication to
me from abroad by Octave Gauduin, Chemist, Jean Baptiste Java
Mignon, and Stanislas Henry Rouart, Builders, all of Paris, in the
Republic of France, upon the condition (amongst others) that I, the
said John Henry Johnson, my executors or administrators, by an

page_text: instrument in writing under my hand and scal, 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 YE, that I, the said John Henry Johnson, do hercby
declare the nature of the 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 :-
Many unsuccessful attempts have been made to deposit a layer of
copper upon wrought iron, steel, or cast iron, but the coating of copper
was never sufficiently adherent, and by want of thickness or of homo-
geneity was speedily destroyed. By the new or improved processes
herein-after described, it is easy to cover wrought iron, steel, and cast
iron with a coating of copper, gun metal, yellow copper, aluminium
bronze, or other similar alloys, the said coating being adherent, homo-
geneous, and as thick as may be desired.
Either a dry or a humid process may be used, according to the nature or
thickness of metal to be deposited, or with a view to facilitate the
operation. I shall first proceed to describe the dry process.
For the depositing of a thick coating of copper, gun metal, yellow
copper, or other metals on wrought iron, steel, or cast iron when it is
not necessary to have the said coating perfectly regular, that is, for
covering printing cylinders, large cocks, and other articles, I melt in a
crucible of a form suited to the piece to be coated the quantity of metal
necessary for the deposit, and I cover the surface of the melted metal
with a layer of a flux composed of a mixture of double fluor of alu-
minium and sodium (cryolite) with phosphoric acid. I dip the piece to
be coated into the bath, such piece having been first heated to the
degree of the melted metal, which must cover the whole of the surface
to be coated. All that is then necessary is to allow it to cool in order to
avoid blisters.
For the coppering of wrought iron borax may be used, but for cast
iron or steel it is necessary to employ the aforesaid flux, as borax does
not scour cast iron or steel.
To render the work easier the following arrangement may be used :-
The metal to be deposited, namely, copper, gun metal, or yellow metal,

page_text: is melted in a crucible of natural or agglomerated carbon having the
form of a semi-cylindrical trough, the flux being lighter remains on the
surface of the melted metal to prevent oxidation, and to scour the sur-
faces to be coated. The wrought or cast-iron cylinder, if such be the
article to be coated, is supported on its axle, and has only a part of its
circumference in the melted metal. When a sufficient degree of heat
has been obtained, the entire surface of the cylinder is brought in contact
with the metal to be deposited by imparting a rotatory motion to the
cylinder, such rotary motion being continued till a sufficient thickness
of coating has been attained.
I shall now proceed to describe a dry process, with or without an
electric current. This process is used for depositing a light or thin coat
of copper on manufactured goods. A mixture of one part of dry,
chloride or fluoride of copper and five or six parts of cryolite, to which
may be added a certain quantity of chloride of baryium to render it
more fusible, is melted in a crucible or in an oven made of carbon.
The proportions given may be varied considerably.
When the mixture is well melted, the wrought iron, steel, or cast iron
goods to be coppered and scoured are first dipped in the mixture, and
acting by way of affinity they remove the copper from its combination,.
and are covered with an adherent coat more or less thick, according to
the duration of immersion, and to the degree of concentration of the
bath. The use of an electric current having the negative pole in contact
with the goods to be coppered, and the positive pole with an ingot of
copper immersed in the bath, affords the advantages of keeping the
mixture constant, and of making the deposit more easily. A crucible of
copper,
which may
form part of the circuit, may also be used.
Other salts of copper, mixed or not with cryolite or with other alkaline
salts or earthy alkaline salts, may give the same results, but the Inventors
claim as their Invention the decomposing of the melted simple salts of
copper, alone or combined with other salts by way of affinity, or by
electric decomposition.
I shall now proceed to describe the humid process. Many copper
salts, alkaline or neutral, mixed with water have been tried without
success to deposit on wrought iron, cast iron, or steel a thick adherent
and continuous coat of copper. The scouring of wrought and cast iron
is never perfect, and the bath used could not complete the said scouring.

page_text: It has been observed that for coppering wrought iron, steel, or cast iron
it is necessary to work in a very acid solution capable of dissolving the
oxides of iron remaining after the scouring, without however attacking
the metal itself. Such a solution acts continually by its scouring pro-
perties on the places where the copper is not yet deposited, and dissolves
the oxides which would prevent the deposit. Morcover, the acidity of
the solution greatly improves the physical properties of the deposit,
which becomes adherent, malleable, and ductile, and by its great con-
ductibility reduces the expense of electricity.
Many organic acids, and especially the organic polobasies, tartaric,
oxalic, succinic, citric, malic, and other acids having similar properties
combined with oxides of copper and other alkaline oxides in the state
of double acid salts, as in the bi-tartrates, bi-oxalates, quadr-oxalates,
bi-succinates, bi-citrates, bi-malates, alkaline combined with corrc-
spondent copper salts and excess of acid when they do not attack too
deeply the iron are more or less capable of giving a good deposit. The
oxalates of copper combined. with a considerable excess of bi- or
quadr-oxalates of sodium with excess of acid, and dissolved in ten or
fifteen times their weight of water also give a good deposit on wrought
iron, cast iron, or steel. Sixty to ninty degress centigrade of heat will
facilitate the process.
When a great thickness of copper is required the use of an electric
current becomes necessary. For scouring the metals and for using the
electricity the ordinary methods are employed. For depositing alloys
of copper and zinc, copper and tin, copper and aluminium on wrought
iron, cast iron, or steel, it is sufficient to mix with the baths of copper
above described a similar bath of zinc, tin, or aluminium in quantity
inversely proportioned to the electric conductibility of the two baths,
and to operate with soluble anodes made of yellow copper, gun metal, or
aluminium bronze. The same results may be obtained by working for
a short time in a bath of copper with a soluble anode made of yellow
copper, gun metal, or aluminium bronze, or rather of zinc, tin, or
aluminium, taking care to properly proportion or regulate the tension of
the electric current to the surface to be covered. This condition is
essential to the success of the operation, because a weak current affects
only the salt of copper, while a stong current rather affects the zinc, the
tin, or the aluminium.
The coppering of wrought iron, cast iron, or steel by these processes

page_text: may be used as an intermediate between those bodies, and lead when it
is necessary to cover them entirely or partially with a solid coat of lead,
as is the case for covering projectiles. Zinc has hitherto been used as an
intermediate for such coverings of lead.
The projectile is coppered by any one of the herein-before described
processes, and when this first result is obtained the projectile is heated
to two hundred or three hundred degrees centigrade, and scoured in a
solution of chloride of zinc and dipped in a bath of melted lead heated
to a degree a little above its point of fusion. When extra thickness
is required a mould may be used and the lead cast in the space between
the mould and the projectile.
Having now described and particularly ascertained the nature of the
said Invention, and the manner in which the same is or may be used or
carried into effect, I would obscrve in conclusion that what I consider to
be novel and original and therefore claim as the Invention secured to
me by the herein-before in part recited Letters Patent is,-
First. The peculiar dry process and the necessary apparatus hercin
referred to for depositing thick coats of metal on articles composed of
wrought iron, steel, or cast iron, as herein-before described.
Second. The use of a dry process of precipitation or deposition based
on the decomposition of simple or compound salts of copper kept in
fusion, in conjunction or not with electric currents, as and for the
purposes herein-before described.
Third. The peculiar humid process of precipitation or deposition of
copper and of its alloys with or without the aid of electricity, as and for
the purposes herein-before described.
In witness whereof, I, the said John Henry Johnson, have to this
my Specification set my hand and scal, this Nineteenth day of
June One thousand eight hundred and seventy-three.
.