Improvements relating to the Coating or Covering of Metals and other Substances with Metals and other Materials by the Aid of the Electric Arc.
Year: 1896

page_text: Date of Application, 11th Nov., 1896-Accepted, 1st May, 1897
COMPLETE SPECIFICATION.
Improvements relating to the Coating or Covering of Metals and
other Substances with Metals and other Materials by the Aid
of the Electric Arc.
I, FREDERICK HALL SNYDER, of Jersey City, State of New Jersey, United
States of America, Engineer, now of Westcombe Park Works, Westcombe Park,
in the County of Kent, do hereby declare the nature of this invention and
in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement:-
. My invention relates to the coating or covering of metallic and other bodies
or structures of various descriptions with metals or alloys and with other materials
by the aid of the electric arc.
By my said invention the bottoms or other parts of iron or steel ships, bridges
and other metallic structures, after they are built, may be thoroughly coated with
a metal or alloy.
I am also enabled by my said invention to produce vitreous coatings or coverings
upon brick, stone, metal and other structures.
The chief object of the said invention is to prevent the oxidation and
consequent rust and deterioration of the bottoms and the interior surfaces and
bulkheads of iron or steel ships, and to prevent or reduce to a minimum the
growth of weeds, grass or barnacles on the bulls of such ships and the consequent
fouling of the surface thereof, and thus obviate the necessity of frequent docking
and painting, and increase the speed of the vessel.
While, however, the primary object is the coating of the interior and exterior
of the hull and the bulkheads of sea-going vessels, the said invention is also.
applicable to the coating of other structures, such, for instance, as bridges, piers,
vats for holding acids or other liquors, buildings, lamp-posts, pillar-boxes, safes,
machinery, ordnance, statuary or any other structures which it is desirable to
protect against oxidation and corrosion.
According to one method I proceed as follows, viz. :-I mix a metal or alloy,
in the form of filings or of powder, with a suitable glutinous or binding material,
such, for instance, as rye-flour or starch, so as to produce a thick paste of about
the consistency of mortar; I then smear or plaster the said paste upon the
surface of the structure upon which the coating is required, to a greater or less,
thickness according to the desired thickness of the coating; I then fuse the said
metal into or onto the metal of the said structure by connecting the latter with
the negative pole of a dynamo-electric machine or other source of electricity,
and then holding in proximity to the said structure a carbon or other electrode
connected with the positive pole thereof, so as to form an electric arc, the said
carbon or other electrode being held in turn over every part of the surface to
be coated or being moved slowly to.and fro over such surface.
If the surface of the metallic coating thereby produced is rough or uneven,
I pass over the same a hollow smoothing iron heated internally, by means of a
blow-pipe flame or by electricity or in any other convenient manner, to a high
temperature sufficient to melt the metal protuberances and cause the same to
blend with the other parts of the metal applied.
.
In coating or covering a structure with glass or other vitreous material,
according to my said invention, I smear or plaster over the surface of the

page_text: structure to be, coated or covered, a vitrifiable composition or glaze, such, for
instance, as a solution of silicate of soda or other silicate, or powdered glass
mixed as above described with a glutinous or binding material, the composition
or paste being mixed with sulphate of copper or other suitable substance which
will serve to conduct the electric current through the same; I then fuse the glass
or vitreous material into or onto the substance of the structure as above described,
by means of the electric arc.
In coating or covering structures of brick, stone or other substances which are
not good conductors of electricity, I hold the negative pole of the source of
électricity in close contact with the vitrifiable composition or glaze applied to
the surface of the said structure, in proximity to the point near to which the
carbon or other electrode connected to the positive pole is held for the purpose of
producing the electric arc, the two electrodes being moved over the surface to
be coated as required.
In cases where glass or a vitreous coating or covering is to be applied to a
structure of metal or other substance which is a good conductor of electricity,.
I connect the negative pole of the electric generator to the said structure and then.
fuse the vitrifiable substance or glaze into or onto the metal or other substance
by the electric are as above described.
By this part of my said invention I am enabled to produce vitreous coatings or
coverings of any desired colour or of two or more different colours on brick or
stone walls or other surfaces. For instance I can coat the walls of vaults or the
like in such a manner as to render the same damp-proof, as a seamless covering
can be thus produced over their entire surface.
Having now particularly described and ascertained the nature of my said inven
tion and in what manner the same is to be performed, I desire it to be understood
that I do not claim broadly or irrespectively of my improvements herein described
the use of the electric arc for fusing metal to a metallic surface; but I declare
that what I claim is
First. The herein described method or process of coating or covering bodies or
structures with metals or alloys, consisting in finely dividing the metal or alloy and
mixing it with a glutinous or binding material, then plastering or smearing the
plastic mixture over the surface of the body or structure and then fusing the metal
or alloy to such body or structure by means of the electric arc, substantially as
herein before described.
Second. Coating or covering metal and other bodies or structures with glass or
other vitreous material by the aid of electricity, substantially as herein before
described.
. Third. The herein described method or process of coating or covering bodies or
structures with glass or other vitreous material, consisting in smearing or spreading
over the surface of the body or structure a plastic mixture of a suitable silicate, or
of powdered glass and a glutinous or binding material, with a substance which is a
good conductor of electricity, and then fusing such mixture by the electric arc.
Fourth. An object or structure coated with a metal or alloy in the manner
substantially as hereinbefore described.
Fifth. An object or structure coated or covered with glass or other vitreous
material in the manner substantially as hereinbefore described.
Dated the 5th day of February 1897.
D. YOUNG & Co.,
11 & 12 Southampton Buildings, London, W.C.,
Agents for the Applicant.

page_text: Date of Application, 11th Nov., 1896-Accepted, 20th Mar., 1897
COMPLETE SPECIFICATION.
Improvements relating to the Coating, Covering, or Amalgamating
of Metals with Metals by the Aid of Electricity, and to Apparatus
therefor.
I, FREDERICK HALL SNYDER, of Jersey City, State of New Jersey, United
States of America, Engineer, now of Westcombe Park Works, Westcombe Park,
in the County of Kent, do hereby declare the nature of this invention and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement :-
My invention relates to the coating or covering of metal bodies or structures of
various descriptions with gold, silver, copper or other metals or alloys, by the aid
of electricity in such a manner as to effect a coalescence or amalgamation of the
metals.
My said invention also comprises apparatus for use in the production of the
metallic coatings.
By my said invention the bottoms or other parts of iron or steel ships, bridges
and other metallic structures, after they are built, may be thoroughly coated with
a metal or alloy, more effectually than can be done either by the electro-plating
or depositing processes ordinarily employed, or by dipping the ship, bridge or
other structure (if this were practicable) in a bath and coating the same by
what is commonly known as the galvanising process, the metal or alloy in my
process being forced or drawn into or amalgamated with the substance of the
metallic structure, instead of being merely deposited upon the surface thereof as
heretofore.
The primary and chief object of the said invention is to prevent the oxidation
and consequent rust and deterioration of the bottoms and the interior surfaces and
bulkheads of iron or steel ships, and thus obviate the necessity of frequent docking
and painting. This object is efficiently accomplished by the present invention, as
a suitable coating of copper or other suitable metal properly applied by my process
will not only last as long as the vessel itself, but will greatly prolong the life of the
same. It will also, when applied to the exterior of the bottom and sides of a ship,
materially decrease skin-friction, thereby increasing the speed of the vessel, and,
when a suitable metal is used for the coating, the growth of weeds, grass or
barnacles and the consequent fouling of the surface of the ship's hull will be
reduced to a minimum.
While, however, the primary object is the coating of the interior and exterior of
the hull and the bulkheads of seagoing vessels, the said invention is also applicable
to the coating of other structures, such, for instance, as bridges, iron piers, iron
vats for holding acids or other liquors, iron buildings, lamp-posts, pillar-boxes, iron
safes, machinery, ordnance, statuary or any other structure which it is desirable to
protect against oxidation and corrosion. It is also useful for applying gold, silver,
platinum, nickel or other metals in the place of the usual processes of electro-
plating, being, as above stated, far more efficacious than such processes; and also
for coating plates or vessels with gold, platinum or other metals for electrical
purposes.
In coating metals with metals according to my method or process, I make
the metal body or structure to be coated serve as the kathode, and I. employ

page_text: a metal anode enclosed in a brush or similar device which I moisten or saturate
with a suitable metallic salt or solution and then pass over the surface of the
structure after the manner of painting, taking care not to allow the said brush or
the like to remain stationary while in contact with the said surface.
I make the said brush or other electrolyte-carrier of such form and dimensions
that there will be a very small area of contact surface between the same and the
metal body or structure, and in conjunction with such small area of contact surface
I employ an electromotive force and density of current very much greater than
are ordinarily used in electro-plating. The electromotive force which I employ is,
in fact, much greater than is necessary to effect the decomposition of the metallic
solution, and is such as would, were the brush or other electrolyte-carrier to remain
stationary in contact with the kathode, cause the burning or overheating of the
said brush or the like and the deposit of the metal in a pulverulent or granular
state; and I am enabled to use such a high electromotive force by reason of the
fact that I keep the brush or other device moving while it is in contact with the
said metal body or structure.
In coating a ship or other metal structure with metals or alloys according to one
method, I proceed as follows:-
I first clean and brighten the surface of the metal to be covered, for example by
the use of potash, acids, or a sand-blast, the latter being preferable in the case of
large structures, such as, ships, bridges and the like. I then connect the negative.
pole of a dynamo-electric machine or other suitable electric generatur, to the vessel
or other structure to be covered or coated; and to the positive pole of the electric
generator I attach an insulated wire; to the terminal of this wire, I attach a metal
anode enclosed in a brush or other suitable electrolyte-carrier, such, for instance,
as is hereinafter described, for applying the metallic solution to the said structure,
The brush so connected I moisten or saturate with the desired metallic solution,
and I rub or smear the same over the surface of the structure to be coated, after
the manner of painting, taking care, as above stated, not to allow it to remain
stationary while in contact with the kathode.
The metallic solutions which I employ I prepare substantially in the same
manner as those used in ordinary electroplating; but, as above stated, I employ
a much higher electromotive force, and for the metals or alloys of low cou-
ductivity I use a greater electromotive force than I employ for those of better
conductivity.
In all instances, with whatever metal I am operating, I employ as high an E.M.F.
as is practicable, and more than quadruple that usually employed in electro-
plating or depositing. For coating structures with metals or alloys of low
conductivity, I use an E.M.F. of about 50 to 70 volts, the current being about
from 25 to 40 ampères. And I find that, with metals or alloys of better con-
ductivity, the E.M.F. should not be less than about 25 to 30 volts, the current
being about 10 to 15 ampères.
For example, in coating an iron or steel structure of large size with copper,
I employ a brush such as is hereinafter described of about six inches in width and
say one-inch to one-inch-and-a-half in thickness, and I use an electromotive force
of from 25 to 30 volts, the current being from 10 to 15 ampères. With alloys
of copper having a lower conductivity, however, I can use a higher electromotive
force.
By this improved method or process I effect a perfect union or coalescence of the
metals such as cannot be obtained by the ordinary electroplating or depositing
processes, and such union or coalescence takes place instantaneously, that is to say,
when the structure and the brush are connected with the source of electricity, and
the brush moistened or saturated with the desired metallic solution is applied to
the surface of the structure, as above described, the metal is instantly formed
from the solution and forced or drawn into the surface to be coated, so that the
metal can. be applied as quickly as a coat of paint.
Unlike the electro-plating process, the metal is not merely deposited upon the

page_text: surface, but enters the substance of the structure, so that it is practically impossible
to separate the metals by scraping, filing or the like, and oxidation or rust between
the two metals is effectnally prevented.
As above indicated, I vary the electromotive force according to the conductivity
of the metal or the nature of the metallic solution to be applied; and I find it more
advantageous to employ alloys of metals, such, for instance, as bronze or Muntz
inetal, with which a much higher E.M.F. can be used than with the virgin metals.
I also find that the higher the voltage or E.M.F., the more perfectly is the metal
forced or drawn into the structure to be coated.
Any person skilled in the art to which my invention pertains, can readily.
ascertain how high an electromotive force can be used with advantage. And by
watching the action taking place between the brush and the structure being coated,
the operator can immediately tell when the electromotive force becomes too weak,
as the action will then cease.
For applying the metallic coating in the form of salts or a chemical solution of
the metal, as above described, I employ a device which I term a brush, consisting
of asbestos or other suitable material secured in a handle of wood or other
suitable insulating material, and connected, by a suitable insulated conductor
extending through such bandle, with the positive pole of the electric generator.
In the accompanying drawing I have shown one form of my improved brush.
Figure 1 is a sectional elevation of the said brush.
Figure 2 is a section on the line x, x Figure 1, and
Figure 3 shows extended to its full length a piece of asbestos-cloth or similar
material forming part of the said brush.
a is the handle, which is made of wood or other suitable insulating material.
b is the piece of asbestos-cloth or the like. c is a T-shaped piece or anode of metal,.
the stem e of which is passed first through a hole b¹ in the piece b of asbestos-cloth
and then through the handle a. I prefer to make this T-shaped piece or anode of
copper or other suitable metal which is a good conductor of electricity. d is a nut.
screwed upon the said stem and whereby the said T-shaped piece or anode is
drawn forcibly into the handle a so as to draw the asbestos-cloth partly into a
transverse slot or groove a' in the wider end of the said handle. is an insulated
conductor whereby the said T-shaped piece or anode is to be connected to the-
positive pole of the source of electricity.
Where salts or other chemical solutions of the metals are used, and a thick
coating is desired, I apply several coatings in succession, this, however, is rapidly
accomplished, and the coating may be brought to any required thickness.
I also, in some instances, effect the application of two or more separate metals or
chemical solutions thereof, by first applying one coat, such, for instance, as copper
to the structure, and afterwards applying to the said structure thus coated with
copper, a coating of lead or other metal or alloy or chemical solution thereof.
When different metallic coatings are used, it is necessary, as above stated, to use
an electromotive force, varying according to the conductivity of the metal and to..
the nature of the solution employed.
I sometimes make plates, electrodes or cells for electric batteries by my.
improved process above described, by coating copper or other suitable metals or
alloys with platinum, gold, silver or other useful and durable metals or alloys.
adapted for the purpose.
In carrying into effect the above-described methods or processes, I do not
confine myself to the use of any special kind of metal or alloy for the purpose
of forming the coating, nor to the use of the salts, sulphates or any chemical
product or solution of the metals; as I can, in some instances, use a metallic,
solution of the virgin metal alone as hereinbefore described, while in other.
instances I use alloys of different metals, or chemical compounds of the same.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I desire it to be understood..

page_text: that I am aware that it has been proposed to eléctro-plate metal objects by
connecting the object to be coated to the negative pole of a source of electricity
and a pad saturated with the metallic solution to the positive pole thereof, and
then applying such pad to the surface of such object for a sufficient length of
time to permit the deposition of the metal with an electromotive force and current
such as are ordinarily employed in electro-plating; but I do not claim the
deposition of metal upon metallic bodies or structures when this is effectel by a
low electromotive force and with a low current density such as are commonly used
in the electro-plating or depositing processes, as such an electromotive force and
current will not effect the result which it is the object of my invention to attain ;
but I declare that what I claim is:-
First. The coating or covering of metal bodies or structures with metals or alloys
by a method or process such as I have herein before described, in which a very
high electromotive force and current density are employed in conjunction with
movement of the brush or other electrolyte-carrier in contact with the body or
structure and small area of contact surface between such electrolyte-carrier and the
said body or structure, for the purposes above specified.
Second. The improved method or process of providing a metal body or
structure with a metallic coating, consisting in connecting the said body or
structure to the negative pole of a source of electricity, and then passing over the
surface of the said body or structure, as in painting, a brush or the like moistened
or saturated with a metallic salt or solution and containing a metal anode
connected to the positive pole of the said source of electricity, while a current of
very high electromotive force is passing through the circuit, taking care not to
allow the said brush or the like to remain stationary while in contact with the
said body or structure, substantially as and for the purposes hereinbefore
described.
Third. Coating plates, electrodes or cells for electric batteries with platinum,
gold or other suitable metal or alloy by my improved method or process,
substantially as hereinbefore described.
Fourth. The improved brush or electrolyte-carrier constructed with the metal
anode substantially as described with reference to the accompanying drawing and
for the purpose specified.
Fifth. An object or structure coated with a metal or alloy in the manner
substantially as herein before described.
Dated the 11th day of November 1896.
D. YOUNG & Co.,
11 & 12 Southampton Buildings, London, W.C.,
Agents for the Applicant.