New or Improved Method of Attaching Copper or other Antifouling Metal Sheathing to the Lower Portions of Metal Ships.
Year: 1895

page_text: Date of Application, 13th Feb., 1895
Complete Specification Left, 13th Dec., 1895-Accepted, 8th Feb., 1896
PROVISIONAL SPECIFICATION.
New or Improved Method of Attaching Copper or other Antifouling
Metal Sheathing to the Lower Portions of Metal Ships.
We, RICHARD ROPER, and LEOPOLD ROPER, of Palace Chambers, 9 Bridgeo
Street, Westminster, in the County of London, Marine Contractors' Engineers, do
hereby declare the nature of this invention to be as follows:-
Heretofore when sheathing the lower portions of iron ships with copper or other
antifouling metal plates it has been usual to first cover those portions of the vessel
to be protected with a sheathing of timber-generally varying between 4 and
This method is
9 inches in thickness, and nail the copper or other plates thereto.
not only expensive but defective in several respects, and our invention has for its
object to overcome these objections.
For this purpose we rivet or otherwise secure the plates of copper or other
antifouling metal to frames or grids of brass or other metal between which and the
plates no galvanic action whatever will take place, and these frames or grids we
then fill with wood or other packing and secure them in position by screws or bolts
passing through them and the plates into or through the hull of the vessel, after
the latter has been cleaned and suitably insulated, we then put on a layer of felt
saturated with black varnish, or other suitable solution.
The plates are so arranged that each overlaps those next it (in the usual manner)
on one side and at that end nearest the stern of the vessel, and where said plates are
riveted to the frames or grids we preferably employ rivets so shaped that they may
be first riveted to the frames in the usual manner and their heads then employed
for riveting the frames and plates together.
With such an arrangement the hull of the vessel need not be thickened to any
great extent, whilst should any of the plates be damaged they may be quickly
removed and replaced by new ones.
Dated this 13th day of February 1895.
CASTLE SMITH,
Invention" Office, 54 Fleet Street, London, E.C.,
Agent for the Applicants.
New or Improved Method of Attaching Copper or other Antifouling
Metal Sheathing to the Lower Portions of Metal Ships.
We, RICHARD ROPER and LEOPOLD ROPER, of Palace Chambers, 9 Bridge
Street, Westminster, in the County of London, Marine Contractors and Engineers
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:-
Heretofore when sheathing the lower portions of iron ships with copper or other
antifouling metal plates it has been usual to first cover these portions of the vessel to
be protected with a sheathing of timber-generally varying between 4 and 9 inches

page_text: 0
in thickness, and nail the copper or other plates thereto. This method is not
only expensive but defective in several respects, and our invention has for its object
to overcome these objections.
For this purpose we rivet or otherwise secure the plates of copper or other
antifouling metal to frames or grids of brass or other metal between which and the
plates no galvanic action whatever will take place, and these frames or grids we
then fill with wood or other packing and secure them in position by screws or bolts
passing through them and the plates into or through the hull of the vessel, after
the latter has been cleaned and suitably insulated by first painting and then covering
with a layer of felt saturated with black varnish or other suitable water-proofing
and preservative solution.
And in order that our invention may be more readily understood and carried into
practice we will now proceed to describe the same with reference to the accompanying
drawings of which Fig. 1 is a front elevation of a copper or other antifouling metal
plate secured in position according to our method and Figs. 2 and 3 sections on
lines A-B and C-D respectively, on an enlarged scale.
That portion of the ship's bottom to be protected is cleaned, where this is
necessary, and coated with a layer of insulating material a, preferably consisting of
-a coating of paint over which is placed a layer of felt (Figs. 2 and 3) saturated
with black varnish or other suitable waterproofing or preservative solution.
On this prepared surface the copper or other antifouling metal plates 6 previously
rivetted or otherwise secured to frames c (Figs. 1, 2, and 3,) having the opening
thereof filled with wood or the like, are then secured by screws provided with
tapered heads and passing through said plates and their frames into or through the
hull d of the ship.
The frames care of brass or other metal between which and the copper or other
sheathing plates no galvanic action will take place whilst the screws for securing
the plates and their frames in position are insulated from the said plates and frames
and or from the hull of the ship by dipping them into a suitable insulating
⚫composition.
The plates are so arranged that each overlaps those next it on the top side and
at that end nearest the stern of the vessel, and where said plates are rivetted
to the frames or grids we preferably employ rivets so shaped that they may be
first rivetted to the frames in the usual manner and their heads then employed for
rivetting the frames and plates together.
With such an arrangement water will be prevented from reaching the hull and
so setting up galvanic action causing corrosion, and the hull need not be thickened
to any great extent, whilst should any of the plates be damaged they may be quickly
removed and replaced by new ones.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
(1) A method of sheathing the lower portions of ships' hulls with antifouling
plates consisting of first insulating the parts to be sheathed and then attaching the
sheathing plates previously mounted on grids directly thereto by insulated
connections.
(2) The method of sheathing ships with antifouling plates substantially as
described and illustrated in the accompanying drawings.
Dated this 13th day of December 1905
66
CASTLE SMITH,
Invention " Office, Mitre Court, Fleet Street, London, E.C.,
Agent for the Applicants.