IMPROVEMENTS IN THE CONSTRUCTION OF COMPOUND ARMOUR PLATES AND IN THE MODE OF MANUFACTURING THE SAME
Year: 1882

page_text: LETTERS PATENT to Thomas Deykin Clare of Handsworth in the County of
Stafford for an Invention of "IMPROVEMENTS IN THE CONSTRUCTION OF
COMPOUND ARMOUR PLATES AND IN THE MODE OF MANUFACTURING THE
SAME Communicated to him from abroad by Frederic Yates of Unkel on
the Rhine. Prussia
"
PROVISIONAL SPECIFICATION left by the said Thomas Deykin Clare
at the Office of the Commissioners of Patents on the 20th October 1882.
THOMAS DEYKIN CLARE of Handsworth in the County of Stafford " "IMPROVE-
MENTS IN THE CONSTRUCTION OF COMPOUND ARMOUR PLATES AND IN THE MODE
OF MANUFACTURING THE SAME" [Communicated to him from abroad by
Frederic Yates of Unkel on the Rhine, Prussia]
My invention has for its object improvements in the construction of compound
armour plates and in the mode of manufacturing the same by which I am enabled
to produce an armour plate which will resist modern shot and shell more success-'
fully than the present steel faced armour plates besides being lighter and cheaper
for a given resisting power. I am also enabled in many cases to complete the
plates without rolling or hammering which is very expensive when such heavy.
bodies have to be manipulated.. I am also enabled by new combinations of material
to use cheaper metals in the construction of such plates and thus to produce very
strong shields at less cost.
My armour plates consist of a soft wrought iron or steel section or face either
rolled or cast but in certain combinations and constructions of hard steel with
wrought iron or soft steel for the back section of the armour plate with a compound
middle principally composed of soft cast steel, hard cast steel, or other cast metal
such for instance as "Grusons, Fynsporgs Swedish brands, or "Pallisers" in fact
such metal as would be employed for the manufacture of the best chilled shells; or
a fine quality of toughened charcoal iron may be used. With the exception however
of the soft steel and toughened charcoal iron the metals used in the formation of
the centre part should possess the quality of being hardened or chilled.
In the front or outer portions of the face plate conical or other equivalent holes
are formed with their frustra or largest diameter at the front of the plate the
smaller diameter of the frustra of the cone joining into the crown of a hemispherical,
arched, conical, ogival or other kindred recess the base of which is always towards
the centre portion and forming a part of the middle portion of the armour plate at
the base of the front section. In other cases the tapered or conical holes do not end
upon a hemisphere but simply finish with an angle to the body of the centre section.
Dosing £11

page_text: The back section of the armour plate is supplied with conicular pyramidal or other
equivalent holes which are opposite the holes in the front plate the larger portions
of these holes being at the outer face of the back section.
The process is as follows:-The two sections front and back having been
prepared are either placed in a Furnace and heated to the required temperature
and the middle thien enst between the plates while they are still in the Furnace, or
the plates are heated and then placed in a suitable mould which may be partly
composed of iron plates and partly of sand or other suitable material or composition
so as to form the necessary recess to receive the molten metal. In case the centre.
is composed of metal which will chill the front section of the plate would have its
holes in such a way as to enable the metal to be chilled either by a covering of
metal or by other means when the liquid metal is poured in. Now immediately
the centre portion of these compound armour. plates commences to cool the conical
projections of hot hard metal though practically combined with the front and back
plates will bear a distinct relationship to them and they will have the tendency to
draw them nearer together in proportion as the temperature may vary on cooling
between the outside sections and centre of the armour plate thus bringing, a
powerful pressure to bear upon the junction and centre portion of the armour
plate.
In other cases I form recesses of an ogival, globular or conical shape from the
back of the front section but not sufficiently deep to pierce it. Thus a thin portion
of the metal is left in the outer face which allows the compound armour plate to be
rolled if desired in the usual way and at the same time does not prevent the metal
from being chilled or otherwise hardened as the case may be. In other cases the
studs may be inade cylindrical with enlarged bases the front of the studs standing
back in the recesses of the front section sufliciently to allow the compound.armour
plate to be pressed to any desired extent by rolling or other convenient process.
Of course these studs may protrude above the surface of the outer section by
forming the outer mould or chill plate for that purpose where the special purposes
for which the plates may be intended required such.
It is well understood and an established fact that the cast metal known as
"Hart-Guss" proposed in some cases to be adopted for the middle or second section
of the plate resists the penetrating action of projectiles in a maximum degree and
can only be ultimately penetrated or destroyed by being broken up to fragments
from being greatly overmatched and then by repeated blows. There is therefore
every reneon to believe that if adequately protected in the special manner I propose
from the direct blow and smashing effect of the projectile all that could happen
would be cracking; but such cracks would remain probably only cracks and in that
case no projectile would ever get through the plate until it was pounded by
repeated blows to small fragments. The hardened or chilled studs would of course
have the effect of breaking up or diverting the projectile in such a way that it
would never penetrate to any great depth in the plate. When the studs were
ogival for instance it would be similar to one shell meeting the other point to point
or head to head.
Another modification of my invention is produced by a wrought iron or other
tough back section with a front section of soft tough steel. The composition of
this front section is the special feature in this modification and is as follows:-
Under the surface of the front section are spheres or hemispheres. of hard steel or
cast metal or hard wrought iron which are imbedded in the soft tough steel. There
may be spheres near the front face of the front section and hemispheres behind the
spheres with a division or not of the soft tough steel, the base of the hemispheres
or equivalent figure resting upon the back section. There may be a wrought iron
plate at the front of the section which contains the spheres or lumps when desired.
These plates would be manufactured in the following manner-The back section
would be rolled in the ordinary manner and placed hot in the mould or heated in
a furnace and the mould formed in the furnace. In either case: if cast flat the
hemispheres or other equivalent lumps of steel, wrought iron, or hard cast metal

page_text: would be placed upon the plate at intervals in the mould or chill and the spheres
then placed in the recesses left between the hemispheres and upon them the soft
tough steel would then be poured into the mould joining the whole into one solid
compound plate-In case of there being a front soft plate of wrought iron that
would also be placed in the mould before casting in the required position. The
spheres, hemispheres or other lumps would themselves be cast or otherwise
enveloped in metallic capsules or cases which might be stamped in halves or other
sections as found most convenient from such metal as charcoal iron or other metal
to suit the internal and external metals to be used so as to form a welding or
uniting medium between the spheres and the body of the armour plate. This device
I adopt in regard to some combinations of metals in the previous modifications
indeed whenever the natures of the metals to be combined require such uniting
medium. But in the case of the spheres they may sometimes be cast to turn
round when struck so as to divert the shot still more effectively. If these
compound plates require casting on their side the spheres, hemispheres or other
lumps are strung together upon rods or hollow tubing through which water may
be passed to prevent their too easy destruction and forming a support in the mould
the metal being run into and flowing around the supports and spheres uniting the
whole into one compound plate.
Armour plates thus composed would offer most formidable opposition to the
entrance of any projectile because immediately the point of the projectile had
entered the soft tough steel it would be in contact with the spheres or hemispheres
or other lumps of hard metal which would defy penetration and the projectile
would have to alter its direction or otherwise force the obstacle. In some cases I
form this last modification of three layers viz 1st The front section of soft tough.
steel containing the spheres or other lumps: The 2nd section of hard steel or other
hard metal and the back or 3rd section of wrought iron. In this case the
manufacture would be as follows:-1 The wrought iron back section would be.
prepared in the usual way by rolling or otherwise: 2nd The front section of soft
tough steel would be cast around the spheres or other lumps: 3rd The centre section
of hard metal would be cast between the wrought iron back section and the
compound front section thus completing the casting and general formation of the
compound armour plate.
I also form compound armour plates with the front section rolled from wrought
iron or other soft metal having ribs or corrugations preferably of a V shape at their
inner side. The back section would also be of wrought iron with the conical or
other holes as previously set forth, the centre section being of hard metal run in
between the front and back sections.
There are of course many changes of positions possible in the combinations of
these compound armour plates such as the following:

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Thomas Deykin Clare in the Great Seal Patent Office on the
20th April 1883.
THOMAS DEYKIN CLARE of Handsworth in the County of Stafford ." IMPROVE-
MENTS IN THE CONSTRUCTION OF COMPOUND ARMOUR PLATES AND IN THE MODE
OF MANUFACTURING THE SAME" (A communication to me from abroad by
Frederick Yates of Unkel on the Rhine, Prussia)
My invention has for its object improvements in the construction of compound
armour plates and in the mode of manufacturing the same by which I am enabled
to produce an armour plate which will resist modern shot and shell more success-
fully than the present steel faced armour plates besides being lighter and cheaper
for a given resisting power. I am also enabled in many cases to complete the
plates without rolling or hammering which is very expensive when such heavy
bodies have to be manipulated. I am also enabled by new combinations of material.
to use cheaper metals in the construction of such plates and thus to produce very
strong shields at less cost.
My armour plates consist of a soft wrought iron or steel section or face either
rolled or cast but in certain combinations and constructions of hard steel witli
wrought iron or soft steel for the back section of the armour plate with a middle
principally composed of soft cast steel, hard cast steel or other cast metal such for
instance as "Grusons," "Fingspong" (Swedish brands) or "Pallisers" in fact such
anetal as would be employed for the manufacture of the best chilled shells, or a fine
quality of toughened charcoal iron or other iron may be used., With the exception
however of the soft steel and in some cases toughened charcoal iron the metals used
in the formation of the centre part should possess the quality of being hardened
or chilled.
In the front or outer portions of the face plate conical or other equivalent holes
are formed with their frustra or largest diameter at the front of the plate the
smaller diameter of the frustra of the cone joining into the crown of a hemi-
spherical, nrched, conical, ogival or other kindred recess the base of which is always
towards the centre portion and forming a part of the centre portion of the armour
plate at the back of the front section. In other cases the tapered or conical holes
do not end upon a hemisphere but simply finish with an angle to the body of the
centre section. The bick section of the armour plate is supplied with conicular
pyrimidal or other equivalent holes which are opposite the holes in the front plate
the larger portions of these holes being at the outer face of the back section.
The process is as follows: The two sections front and back having been prepared
are either placed in a furnace and heated to the required temperature and the
middle then cast between the plates while they are still in the furnace or the
plates are heated and then placed in a suitable mould which may be partly com-
posed of iron plates and partly of sand or other suitable material or composition so
as to form the necessary recess to receive the molten métal. In case the centre is
composed of metal which will chill the front section of the plate would have its
holes in such a way as to enable the metal to be chilled either by a covering of
metal or by other ineans when the liquid metal is poured in. Now immediately
the centre portion of these compound armour plates commences to cool the conical
projections of hot hard metal though practically combined with the front and back
plates will bear a distinct relationship to them and they will have the tendency
to draw them nearer together in proportion as the temperature, may vary on cooling
between the outside sections and centre of the armour plate thus bringing a
powerful pressure to bear upon the junction and centre portion of the armour
plate.
In other cases I form recesses of an ogival, globular or conical shape from the
back of the front section but not sufficiently deep to pierce it: Thus a thin portion
of the metal is left in the outer face which allows the compound armour plate to

page_text: be rolled if desired in the usual way and at the same time does not prevent the
metal from being chilled or otherwise hardened as the case may be. In other cases:
the studs may be made cylindrical with enlarged bases the front of the studs
standing back in the recesses of the front section sufficiently to allow the compound
armour plate to be pressed to any desired extent by rolling or other convenient
process. Of course these studs may protrude above the outer mould or chill plate
for that purpose where the special purposes for which the plates may be intended
require such.
It is well understood and an established fact that the cast metal. known as
"Hart-Guss" proposed in some cases to be adopted for the middle or second section
of the plate e in cases where there is a front and back protecting plate of softer
metal-resists the penetrating action of projectiles in a maximum degree. There is
therefore every reason to believe that if adequately protected in the special manner
I propose from the direct blow and smashing effect of the projectile all that could
happen would probably be cracking, but such cracks would probably remain only
cracks and in that case no projectile would ever get through the plate until it was
pounded by repeated blows to small fragments. The hardened or chilled studs
would tend to break up or divert the projectile in such a way that it would be
most difficult to penetrate to any great depth. When the studs were ogival for
instance it would be similar to one shell meeting the other point to point or head
to head. These studs are also intended for another purpose: namely when the
plates shall have been cracked to hold up the fragments together in their relative
positions whereas now when broken the pieces fall down or separate and so form
broad cracks which would let a second projectile through to the ships side.
Another modification of my invention is produced by a wrought iron or other
tough back section with a front section of soft tough steel. The composition of
this front section is the special feature in this inodification and is as follows:
Under the surface of the front section are spheres or hemispheres of hard steel or
cast metal or hard wrought iron which are embedded in the soft tough steel.
There may be spheres near the front face of the front section and hemispheres
behind the spheres with a division or not of the soft tough steel the base of thie
hemispheres or other equivalent figure resting on the back section. There may
also be holes, through the centre of the spheres as shown by Figure 20 into which
the soft steel may enter in order to bind the mass namely the balls and soft steel
firmly together. In this case the holes are so placed that they are alternately
horizontal and vertical or placed diagonally in alternating directions. There may
be a wrought iron plate at the front of the section which contains the spheres or
lumps when desired. These plates would be manufactured in the following manner;
The back section would be rolled in the ordinary manner and placed hot in a
mould or heated in a furnace and the mould formed in the furnace. In either case
if cast Bat the hemispheres or other equivalent lumps of steel, wrought iron, or hard
cast metal would be placed and secured upon the plates at intervals in the mould
or chill and the spheres then placed in the recess left between the hemispheres and
upon them, the soft tough steel would then be run into the mould forming the whole
into one solid compound plate. The spheres, hemispheres or other lumps would
themselves be cast or otherwise enveloped in metallic capsules or cases which might
be stamped in halves or other sections as found most convenient from charcoal iron
or other metal to suit the internal and external metals to be used so as to form a
welding or uniting medium between the spheres and the body of the armour plate.
This device I adopt in regard to some combinations of metals in the previous modifi-
cations indeed whenever the natures of the metals to be combined require such
uniting medium. But in the case of the spheres they may sometimes be painted
with blacking or other substance and cast to turn round when struck and thus
divert the shot more effectively. If these compound plates require casting on
their side, the spheres, hemispheres or other lumps are strung together upon rods
or hollow tubing through which water or cold air may be passed to prevent their
too easy destruction and forming a support in the mould the metal being run into

page_text: and flowing around the supports and spheres unite the whole into one compound
plate as shown by Figure 19. But by the withdrawal of the cooling medium after
casting, the tubes may be allowed to inclt thus forming a solid mass.
In some cases I formn this last modification of three layers vis The front
section of soft tough steel containing the spheres or other lumps. 2nd Section of
hard steel or other hard metal, and the back or 3rd Section of wrought iron. In
this case the manufacture would be as follows: 1 The wrought iron back section
would be prepared in the usual way by rolling or otherwise. 2nd The front section
of soft tongh steel would be cast around the spheres or other lumps. 3 The centre
section of hard metal would be cast between the wrought iron back section and
the compound front section thus completing the casting and general formation of
the compound armour plate.
I also form compound armour plates with the front section rolled from wrought
iron or other soft metal having ribs or corrugations preferably of a V shape at
their inner side. The back section would also be of wrought iron with the conical
or other holes as previously set forth, the centre section being of hard metal run in
between the front and back section.
There are of course many changes of positions possible in the combinations of
these compound armour plates.
In order that my invention may be clearly understood and more easily carried
into practice I have appended hereunto two sheets of drawings which I will now
proceed to explain.
Figure 1 is a broken off plan of one of my armour plates.
Figure 2 is a section of the plate on line C. D.
Figure 3 is a section of the same plate on lineė A. B.
The front plate N has holes n' pierced in it with their largest diameter at the
outer portion of the plate and the smaller end n joining into the crown of the
hemispherical or other recesses n³ It is not however necessary to always hollow
the back part of the front plate N as the cones may finish with a simple angle as
shown in the section Figure 6. The back section P has similar holes p' formed in
it just opposite the front holes n' and these have their smaller part p? towards the
inner portion of the plate. Intermediate holes n' may also be used with smaller
hemi-spheres or other figures n with similar holes p opposite in the back plate P.
The centre part 0 of the plate is run in a molten state between the plate N and P
filling up the recesses and the whole becomes united together as one solid plate the
front N and P being drawn together as contraction of the centre part O takes place.
Figure is a plan of a similar plate with Figure 5 a section on line G, H and
Figure 6 a section on line E. F. It will be noticed that in these figures the holes
are near together and thus there is not so much room for hollowing out the inner
portions of the holes in the back and front plates.
The recesses in the plates may be considerably varied, for instanco:-Figure 7
and 8 may be used with their hidden heads S under the surface of the front plate
and other holes T in the back plate opposite. The flat top studs n' might stand
back also when desired. In either case there would be no difficulty in rolling the
plate after casting the centre portion because the hard studs would be covered and
thus the rolls would be protected from injury while rolling. In other cases where
rolling is not required the studs may project above the surface of the plate as.
shown by broken off section Figure 17 where either the hemispheres 8' or other
bases may protect the projecting points 8 or rings may be formed such as that
shown by 8 of which there may be one or more to each projecting piece. These
projecting points ay be chilled or otherwise hardened according to the kind of
metal forming the centre part by simply using proper chilling plates when casting
the centre portion.
Another kind of armour plate is shown by Figure 10 in plan. Figure 11 being a
section on line J. K and Figure 12 on line L. M. The back plate U may be
composed of any tough material such as wrought iron or tough steel but the front
portion is very novel in is construction. The splicres V and hemispheres W

page_text: which are composed of hard metal as before explained are placed in the mould and
the soft tough metal is run around them uniting the whole together in one solid
plate. If these plates are cast flat then the hemispheres W are placed with their
bases upon plate U and the spheres V are placed upon them and the metal then run.
If however the plate is cast on edge they would be supported in the mould either
by a light frame work of metal or by passing tubes right through the spheres upon
which the spheres would be supported while the metal was being run. These
tubes could be kept cool by circulating water or cold air through them for a time
to be stopped as the metal commenced to set thus allowing the tubes to be burnt
away after a time or the holes could be left in.
Figures 9, 13 and 14 are various modifications of some of the variations which
may be adopted without departing from the principle of my invention. In
Figure 9 the front plate X and the back plate with the end plate uniting
the two former by dovetails and similar end plates to a² also dovetailed from an
open topped mould to receive the spheres and the centre part when poured in.
•
The modification Figure 13 has only a back plate Y and the frame y' and y*
with similar side plates to form a mould.
The modification Figure 16 is similar to Figure 9 but having no projecting
pieces into the front plate.
The modifications Figures 14 and 15 are composed of rolled front plates Z and
back plates Qwith the centre 3 run between them so uniting them practically
into one plate. The shape of the ribs may be modified very considerably but I
have shown the V rib and the parabola rib.
:
Armour plates thus composed as herein explained would offer most formidable
opposition to the entrance of any projectile because immediately the point of the
projectile had entered and gone clean through the soft tough steel or iron it would
be in contact with the spheres, hemispheres or other lumps of hard metal which
would almost defy penetration and the projectile would therefore have to alter its
direction or otherwise force the obstacle. The object of the soft face plate is to
allow the projectile to make a clean hole without cracking and so prevent the
plate from going to fragments, but there meeting the hard resistance, all of which
will tend to hold the plate together when the inside cracks.
It will be evident to any practical man that many changes may be made of
various parts without departing from the spirit of my invention. For instance
the wrought iron sides y and y2 Figures 9. 13 and 16 may be used to other
combinations shown. It will also be evident that spheres of very hard metal may
be combined with less hard centres in the Figures shown on Sheet 1.
The following table will serve to show some of the changes which may be made
in the composition of these compound armour plates having particular reference to
the shapes shown upon the drawings.

page_text: Having now described my said Invention of improvements in the construction
of compound armour plates and in the mode of manufacturing the same as.
communicated to me I would have it understood that what I claim is :-
First: The manufacture of Compound armour plates with front and back
portions recessed as illustrated by Figures 1, 2, 3, 4, 5 and 6.and united by centre
portions substantially as hercin set forth.
Second The manufacture of compound armour plates with front plate recessed
as shown in the first six Figures to receive the hard middle in combination with
a quite plain tough metal back united by fusion
•
Third: The manufacture of compound armour plates constructed with recesses
such as those shown by Figures 7 and 8 leaving a substance of motal at the front
of the studs S.
Fourth: The compound armour plates as shown by Figures 7 and 8 but with
plain plate at the back not having the recess T.
Fifth-The manufacture of compound armour plates with front plates composed
of tough metal with spheres and hemispheres therein with the back plate U
substantially as shown by Figures 10, 11 and 12 and as berein set forth.
Sixth-The modification shown by Figure 13, with alternating spheres in tough
metal front with soft back Y and soft sides and ends.
Seventh-The modification shown by Figure 9 with tough recessed front plate X
and wrought back 2' with soft side and ends ³ and composite centre substantially
as herein set forth.
Eighth The compound plates shown by Figures 14 and 15 with ribbed centre
and front and recessed back plate substantially ns herein set forth.
Ninth The compound plates shown by Figures 14 and 15 with ribbed centre
but with plain back plates.
Tenth: The construction of Compound armour plates as shown upon the
drawings and as herein set forth
Eleventh The new mode of manufacturing compound armour plates as herein
set forth.
In witness Whereof I the said Thomas Deykin Clare have hereunto set my
hand and seal this seventeenth day of April in the year of our Lord one
thousand eight hundred and eight [sic] three.
THOM MAS
ON CLARE. (L.S.)
ATT TATT