IMPROVEMENTS IN COATING IRON WITH COPPER OR ALLOYS OF COPPER
Year: 1859

page_text: LETTERS PATENT to Thomas Callender Hinde, of Dudley, in the County
of Worcester, Iron Merchant, and George James Hinde, of Wolver-
hampton, in the County of Stafford, Merchant, for the Invention of
"IMPROVEMENTS IN COATING IRON WITH COPPER OR ALLOYS OF COPPER."
Sealed the 15th July 1850, and dated the 25th February 1859.
PROVISIONAL SPECIFICATION left by the said Thomas Callender Hinde
and George James Hinde at the Office of the Commissioners of Patents,
with their Petition, on the 25th February 1859.
We, THOMAS CALLENDER HINDE, of Dudley, in the County of Worcester,
Iron Merchant, and GEORGE JAMES HINDE, of Wolverhampton, in the County
of Stafford, Merchant, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN COATING IRON WITH COPPER OR ALLOYS OF COPPER," to be as
follows:-
Our Invention consists in tinning the iron to be coated with copper or alloy
of copper previous to the immersion of the said iron into the bath of melted
copper or alloy, or of coating the iron with zinc by the process commonly
termed galvanizing before the application of the molten copper or alloy of
copper thereto. The iron may be tinned or zinced by the ordinary well known
processes. We prefer to effect the coating with copper or alloy of copper by
melting the said copper or alloy and immersing the tinned or zinced iron
therein. The iron is quickly withdrawn from the melted metal. By this
treatment the iron is coated with the copper or alloy of copper composing the
1

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Thomas Callender Hinde and George James Hinde in the
Great Seal Patent Office on the 16th August 1859.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, THOMAS
CALLENDER HINDE, of Dudley, in the County of Worcester, Iron Merchant,
and GEORGE JAMES HINDE, of Wolverhampton, in the County of Stafford,
Merchant, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-fifth day of February, in the year of our
Lord One thousand eight hundred and fifty-nine, in the twenty-second year
of Her reign, did, for Herself, Her heirs and successors, give and grant unto
us, the said Thomas Callender Hinde and George James Hinde, Her special
licence that we, the said Thomas Callender Hinde and George James
Hinde, our executors, administrators, and assigns, or such others as we, the
said Thomas Callender Hinde and George James Hinde, our 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 ex-
pressed, 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 COATING IRON WITH COPPER
OR ALLOYS OF COPPER," upon the condition (amongst others) that we, the said
Thomas Callender Hinde and George Janies Hinde, our executors or admi-
nistrators, by an instrument in writing under our, or their hands and seals,
or under the hand and seal of one of us or them, 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 George James Hinde, on behalf of
myself and the said Thomas Callender Hinde, do hereby 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
thereof, that is to say:-
Our improvements in coating iron with copper or alloys of copper consist of

page_text: the methods herein-after particularly explained of preparing the surface of the
iron to be coated, and also of the methods herein-after particularly explained
of annealing and treating the coated iron after its removal from the bath of
molten copper or alloy of copper, in which the iron is immersed in the coating
process.
•
Although for convenience of description we shall herein-after describe our
Invention as applied to the coating of. iron with copper or an alloy of copper
yet we wish it to be understood that by iron we mean iron of the various
qualities, and in the various states of combination in which it is found in
commerce, that is, wrought or malleable iron, cast iron, annealed or malleable
cast iron, steel, and such other metallic compounds or alloys as consist mainly
of iron.
We also wish it to be further understood that our Invention is applicable
to the coating of iron in the shape of bars, rods, wire, plates, or other un-
manufactured form, as well as to the coating of manufactured iron, that is to
say, to articles manufactured from iron.
The preparation, according to our Invention, of the surface of iron to be
coated with copper or alloy of copper, consists in applying to the said surface
a coating of tin or of zinc or of lead, or of any compound or alloy composed
of the metals tin, zinc, and lead, or any two of the said metals. In applying
the said coating of tin, zinc, or lead, or an alloy of these metals to the iron,
we pursue the methods well known and commonly practised of coating iron
with tin or zinc. that is to say, the processes commonly called tinning and
galvanizing. By the process of galvanizing the coating of the iron with zinc,
or with alloys consisting mainly of zinc, may be effected, the process of
coating with alloys of zinc being conducted in the same way as the process
of coating with zinc, excepting that the alloy of zinc is used in place of zinc.
By the process of tinning the coating of the iron with tin, or with alloys
consisting mainly of tin, may be effected, tin or an alloy of tin being used
according as it is required to coat the iron with tin or alloy of tin. The
coating of the iron with lead, or with alloys consisting mainly of lead, may be
effected in precisely the same way as the coating of the iron with tin or alloys
of tin, excepting that lead and alloy of lead are substituted for tin and alloy of
tin respectively. After the iron has been coated with tin, zinc, or lead, or an
alloy of these metals, we conduct the process of coating the iron with copper
or alloy of copper in the following manner:-The copper or alloy of copper is
melted in a crucible or suitably shaped vessel, made of fire-clay, carbonaceous
matter, or other refractory material. The size and shape of the said crucible
or vessel must vary to suit the size and shape of the pieces of iron to be

page_text: coated. The crucible or vessel is heated in a furnace until the copper or alloy
of copper contained therein is completely fused. The iron, prepared by coating
with tin, zinc, or lead, or alloy thereof, as herein-before explained is rapidly
plunged into the molten copper, or alloy of copper and is allowed to remain.
therein until it has acquired or nearly acquired the temperature of the molten
metal. The length of time during which the iron must remain in the bath of
copper or alloy of copper depends upon the size of the pieces of iron to be
coated, and the temperature of the bath, the smaller the pieces of iron the
shorter the time during which they must be allowed to remain in the molten
metal, as prolonged exposure would destroy or injure the article immersed.
The exact length of time during which the immersion should last must be
determined by the experience of the workman. After sufficient immersion the
article is withdrawn from the bath of copper or alloy of copper and placed in an
annealing pan made of iron, fire-clay, or other refractory material, and of a size
and shape suitable to contain the articles to be operated upon. We put in the
said annealing pan fine charcoal dust or iron filings, or iron borings, or iron
turnings, made by preference from cast iron. The charcoal, or filings, or
borings, or turnings are placed so as to be in contact with the surface of the
coated iron in the annealing pan, the articles of coated iron, when their form
admits of it, being stratified or placed in layers alternating with the charcoal
or filings, or borings, or turnings. When the pan is nearly filled with the
coated iron articles, and the charcoal, or filings, or turnings, or borings, amongst
which the coated iron articles are placed, we fill the said pan to the top with
charcoal or filings, or borings or turnings only. We then place on a lid or
loose fitting cover made of the same material as the pan. The covered pan
and its contents are then placed in an annealinug oven or muffle of the ordi-
nary construction, which oven or muffle is heated until the pan and its contents
are at a bright red heat, care being taken that the heat is insufficient to melt the
coating of copper or alloy of copper, or to cause the same to adhere to the iron
filings, or borings, or turnings with which it may be in contact. The heat may
however be carried sufficiently high to effect the incipient fusion of the coating
with advantage. The said incipient fusion gives smoothness to the surface of
the coating. The pan heated to the degree indicated, is allowed to remain in
the oven or muffle about a quarter of an hour (it may however be left much
longer without injury). The pan is withdrawn from the muffle without re-
moving the cover, and the contents are allowed to remain undisturbed until
quite cold. In some instances instead of annealing the coated iron or coated
articles in pans of charcoal, and allowing the same to remain undisturbed till
cold, we adopt the following method, that is to say, we fill a crucible with

page_text: charcoal ground very fine, we place the crucible and charcoal in an ordinary
crucible furnace, and subject the same to heat, and when the charcoal is
heated to near the melting point of the copper or alloy of copper with which
the iron or article of iron to be operated upon is coated, we immerse the
coated iron or article in the heated charcoal, and allow it to remain therein
about fifteen minutes. By this treatment the surface of the coated iron or
articles will be smoother in less time than by the mode of treatment last
described.
Instead of annealing in charcoal we sometimes immerse the iron or articles
after being coated with copper or alloy of copper, either whilst hot or after
having been allowed to cool in a crucible of fire-clay or other refractory mate
rial, the said crucible containing a molten vitreous mixture; and we allow
the coated iron or articles to remain in the vitreous mixture until the oxide.
on the surface of the coated iron or articles has been dissolved by the said
vitreous mixture. The time requisite will depend on the heat (which should
be bright red or thereabouts) and the composition of the molten vitreous
mixture as well as on the size of the article immersed, and the fusibility of the
coating on the iron or article immersed, and must be determined by the expe-
rience of the workman. Care must however be taken that the coated iron
does not remain in the vitreous mixture long enough to remove the coating of
copper, or alloy of copper or portions of it. The coated iron or article when
withdrawn from the crucible is by preference allowed to cool gradually, and
can be freed from the vitreous mixture, or any portion that adheres to it when
cold, by means of a steel hammer; and for this purpose a hammer of a
wedge shape is convenient. The composition of the vitreous mixture may
be greatly varied without materially affecting the result. A vitreous mixture
having the following composition answers well in practice:-Nine parts by
weight of borax, and three parts by weight of common window glass, or eight
parts by weight of borax, and three parts by weight of flint glass.
If the iron which has been coated is in the form of bars, rods, or plates, and
it is wished to give it a smoother surface than it has when taken from the
annealing pan, we pass it through suitably constructed rolls, and if it is re-
quired that the iron should be softened after being rolled, we heat or anneal it
after being rolled in precisely the same manner as we heat or anneal it before
rolling it.
We coat iron wire with copper or alloy of copper, by passing wire that has
been previously coated with tin or zinc, or lead, or an alloy of these metals,
rapidly through the melted copper or copper alloy contained in a trough-shaped
crucible, allowing sufficient time for the wire to become heated to redness in

page_text: passing through the molten metal. The coated wire is afterwards annealed
or heated in the manner already described, and is then drawn in the same
manner as brass wire, and again annealed during the process of drawing it
down to a smaller diameter. If the wire is to be worked into manufactured
articles in a hard state, it must not be annealed after the final drawing, but if
it is required to be used in a softened state. it must be annealed after the final
drawing. The wire may be drawn through the molten copper or alloy of
copper, by being uncoiled from one reel and coiled on another, the said reels
being worked either by hand or by steam power, as is practised in galvanizing
or tinning iron wire. In order to depress the wire under the surface of the
molten metal or alloy during its passage from one reel to another, we fix a
bar of steel across the crucible or vessel, the lower edge of which bar is beneath
the surface of the molten metal or alloy. We pass the wire underneath the
said bar, the said bar being held in its place by sliding into grooves or recesses
in the inner sides of the crucible or vessel. The lower edge of the steel bar
under which the wire is drawn may be provided with a series of semi-circular
indentations which serve as guides for the wire, and the edges of the said
indentations may be rounded so as not to scratch or injure the wire.
As many
wires may be simultaneously drawn through the melted copper or alloy as
there are indentations in the lower edge of the steel bar. The crucible is
provided with several sets of recesses, so that if one of the bars of steel
becomes too hot and in danger of being melted, another bar may be put in
the recess next it, and the overheated one taken out and cooled. The running
of the wire through the molten copper or alloy is thus uninterrupted by the
exchange of the said bars. We prefer to heat the steel bars nearly to a
low red heat before placing them in the crucible in order to prevent the solidi-
fication of the copper or copper alloy upon them on their first introduction
into the crucible or vessel.
When we wish a portion only of a piece of iron to be coated with copper or
alloy of copper, we coat with tin, zinc, or lead, or alloy of these metals, the
portion only that we wish to be coated with copper or alloy of copper; the
part that we do not wish coated is not freed from oxide, as the black scale or
oxide of iron that is on the surface of iron that is rolled whilst hot, and
allowed to cool with free access of air, acts very effectually in preventing the
attachment of the molten copper or alloy of copper, as also does the oxide
found on forged or cast iron that has been allowed to cool with access of air.
By coating the iron with tin, zinc, or lead as described, preparatory to
coating the said iron with copper or alloy of copper, the said copper or alloy of
copper more readily and perfectly attaches itself to the said iron, and by

page_text: annealing the coated iron as described, the copper or alloy of copper with
which the said iron is coated becomes more uniformly distributed over the
said iron.
The method we have described of carrying our Invention into effect, is
applicable without any modification to the coating of wrought or malleable
iron, cast iron, annealed, cast, or malleable iron, and with copper or alloy
of copper. The alloys of copper with which iron may be coated according to
our Invention are brass, or the alloy of copper with zinc, and also alloys of
copper with lead or tin, or mixtures of lead, tin, and zinc. In coating iron
with copper we sometimes employ brass, and give to the said iron a coating
of brass. By prolonged exposure of the iron coated with brass to the annealing
process herein-before described, the zinc of the brass is volatilized, and copper
either pure or slightly alloyed with zinc is left on the article. When the
article has been coated with lead or tin instead of zinc, the coating may be
slightly alloyed with these metals.
Having now described the nature of our Invention and the manner of
carrying the same into effect, we wish it to be understood that we do not limit
ourselves to the precise details herein described, as the same may be varied
without departing from the nature of our Invention; but we claim as our
Invention, firstly, the improvement herein-before described of preparing the
surface of iron or compounds or alloys consisting mainly of iron, to be after-
wards coated with copper or alloys of copper, that is to say, coating the said
iron or compounds, or alloys, consisting mainly of iron, with tin, zinc, or lead,
or alloys of these metals, previous to the application of the copper or alloy of
copper thereto.
Secondly the methods herein-before described of annealing and treating the
iron or compounds, or alloys, consisting mainly of iron coated with copper or
alloys of copper, after the said iron or compound or alloy has received the
coating of copper or alloy of copper.
In witness whereof, I, the said George James Hinde, have hereunto
set my hand and seal, this Sixteenth day of August, in the year of
. our Lord One thousand eight hundred and fifty-nine.
GEORGE JAMES HINDE. (L.s.)
Witness,
5
H. H. MURDOCH.