IMPROVEMENTS IN THE MANU- FACTURE OF THE DESCRIPTION OF CAST IRON HOLLOW-WARE KNOWN AS 'THREE-LEGGED POTS' OR 'NEGRO POTS,' AND IN THE CONSTRUCTION OF STOP BAIL HANDLES FOR CAST IRON HOLLOW-WARE
Year: 1879

page_text: LETTERS PATENT to Thomas Holcroft, of the Firm of Thomas Holcroft and
Sons, of Ettingshall Foundry, near Wolverhampton, in the County of Stafford,
Hollow-ware Founders, for the Invention of "IMPROVEMENTS IN THE MANU-
FACTURE OF THE DESCRIPTION OF CAST IRON HOLLOW-WARE KNOWN AS
'THREE-LEGGED POTS' OR 'NEGRO POTS,' AND IN THE CONSTRUCTION OF
STOP BAIL HANDLES FOR CAST IRON HOLLOW-WARE."
PROVISIONAL SPECIFICATION left by the said Thomas Holcroft at the Office
of the Commissioners of Patents on the 24th December 1879.
THOMAS HOLCROFT, of the Firm of Thomas Holcroft and Sons, of Ettingshall
Foundry, near Wolverhampton, in the County of Stafford, Hollow-ware Founders.
"IMPROVEMENTS IN THE MANUFACTURE OF THE DESCRIPTION OF CAST IRON
HOLLOW-WARE KNOWN AS 'THREE LEGGED POTS' OR 'NEGRO POTS,' AND IN THE
CONSTRUCTION OF STOP BAIL HANDLES FOR CAST IRON HOLLOW WARE."
Firstly. According to this Invention the three legged pots mentioned in the title
are made on what is known as the block method of moulding, the details of the
method being worked out to enable it to be applied to the manufacture of these
special articles. The hedgehog to carry the core is cast upon a base plate supported
on legs to allow the free escape of air under the plate, and also to allow for the
lifting of the plate by hand. A porte is turned at the base of the hedgehog to
receive the core box during the ramming up of the core, and also to receive the
moulding box after the core box is removed and the mould is rammed up. In
addition to fitting round the porte, the corebox (and afterwards the moulding box)
rests upon the base-plate which is turned true.
The corebox is formed in two parts, a lower and an upper. The lower corebox
is divided vertically into halves, the bottom thereof resting upon the base-plate
aforesaid, and fitting around the porte when the halves are fastened together, and
the top having a circular opening formed therein to allow room for ramming up the
core. The upper part of the corebox consists of a bung or plunger fitting into the
circular opening aforesaid, and the underside of it of course is shaped to complete
the hemispherically (or somewhat hemispherically) shaped top of the core (that is,
Price 6d 1

page_text: the bottom of the inside of the pot). The said upper part of the corebox has a
shoulder to bear upon the part of the lower corebox immediately around the
circular opening aforesaid, and thus to prevent the bung from being pressed down
beyond its proper position to complete the shape of the core. The said upper part
of the corebox is provided with handles, and is pressed or rapped down to
complete the core. The core is thus rammed up in the position for casting and
does not require to be turned over. The pattern is formed in two parts, namely,
the body part (which is the lower in the mould), and the part for forming the
hemispherically (or somewhat hemispherically) shaped bottom of the pot The
body part is divided vertically into halves. Each half is cast upon one half of a
base-plate, and the two halves are then bolted together with a thickness piece
between them projecting at each side to form the vertical division for the mould.
A porte exactly corresponding to that at the base of the hedgehog is turned at the
base of the pattern to receive the moulding boxes, the plate as well as the porte
being of course turned true to receive the boxes. The ear patterns are carried one
half on each side of the projections of the thickness piece. The part of the pattern
for forming the hemispherically (or somewhat hemispherically) shaped bottom of
the pot is cast upon a base-plate, and a porte is turned at the base of the pattern
to receive the moulding box. The base-plate is of course turned true to receive
the box. The legs are dowelled to this part of the pattern in the usual manner.
The moulding boxes consist of a lower and an upper; the lower moulding box is
of the depth of the body part or lower part of the pattern, and is divided vertically
into halves. The halves are placed one on each side of the thickness piece
aforesaid, and are bolted together and fit accurately around the porte at the base of
the pattern while this part of the mould is being rammed up. The top of the
lower moulding box is turned to receive the bottom of the upper box when the
mould is put together for casting on the base-plate upon which the hedgehog is
formed. The upper moulding box is in one piece circumferentially, and rests when
being rammed up upon the base-plate of the upper part of the pattern (that is, to
form the bottom part of the pot), and fits around the porte at the base of the said
upper part of the pattern, the said porte corresponding to the top of the lower
moulding box, so that a rebate in the bottom of the upper moulding box which fits
the last mentioned porte fits also the top of the lower moulding box. The upper
moulding box is preferably made in two parts so as to make it deep or shallow
according to the length of the legs, as will be readily understood and as is usually
done.
Secondly. According to this Invention stop-bail handles for cast iron hollow-ware
are formed by making a plain loop at each end of the bail (preferably welded), and
carrying the loop on a cast iron stud projecting from a boss on the pot or other
article, and rivetting a covering washer to the stud, the said boss being provided 4
with a projecting rim or flange closing in the circumference of the opening between
the boss and the washer aforesaid, with the exception of the part necessary for the
travel of the bail. A part of the rim may be left out at the bottom side if desired
to allow dirt or other obstruction to work out.

page_text: DIECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Thomas Holcroft in the Great Seal Patent Office on the 14th June
1880.
THOMAS HOLCROFT, of the Firm of Thomas Holcroft and Sons, of Ettingshall
Foundry, near Wolverhampton, in the County of Stafford, Hollow-ware Founders.
"IMPROVEMENTS IN THE MANUFACTURE OF THE DESCRIPTION OF CAST IRON
HOLLOW-WARE KNOWN AS 'THREE LEGGED POTS' OR 'NEGRO POTS," AND IN THE
CONSTRUCTION OF STOP BAIL HANDLES FOR CAST IRON HOLLOW WARE."
The first part of my Invention relates to the manufacture of "three legged" pots
or "negro" pots upon the system known as the "block" method of moulding, the
details of the method being worked out to afford special facilities for the manu-
facture of these articles. This part of my Invention is illustrated by Figures 1 to 7
inclusive of the accompanying Drawings. The same letters occurring upon any
two or more of the views indicate corresponding parts. Figure 1 is a cross
section through the hedgehog and corebox, and Figure 2 is a plan of Figure 1.
A is the hedgehog to carry the core, and is cast upon a base plate B standing
upon feet C, C, C, (dotted on plan) to allow free escape of air under the plate, and
also to allow for the lifting of the plate by hand. The hedgehog A is of course
perforated with air holes some of which are shown. A porté D is turned' at the
base of the hedgehog to receive the core box during the ramming up of the core,
and also to receive the moulding box (hereinafter described), after the core box
is removed and the mould is rammed up. In addition to fitting around the
porté, the core box rests upon the base plate. The core box is formed in two
parts, a lower and an upper; E, E, is the lower part of the core box and is
divided vertically into halves (similarly as the core box used in moulding oval
pots on the "block" system), the bottom thereof resting upon the base plate B
and fitting around the porté when the halves are fastened together. The top of
the lower part of the core box has a circular opening F to allow room for ramming
up the core. The two halves E, E, are fastened together by means of the pins G, G,
passing through the rings H, H, etc.; whilst the core is being rammed up, the pins
being afterwards uncottered to. allow of removing the core box; K, K, etc., are
handles by which the halves E, E, are moved; J is the upper part of the core box,
and consists of a bung or plunger fitting into the circular opening F. The under-
side of the plunger J is shaped to complete the top of the core. The plunger J has
a shoulder a to bear upon the lower core box, and thus prevent the plunger from
being pressed down beyond its proper position to complete the shape of the core;
b, b, are projecting parts forming handles by which the plunger J is pressed or
rammed down. The profile of one of the handles b is shewn by dotted lines
Figure 1. The core is thus rammed up in the position for casting, and does not
require to be turned over.
The pattern is formed in two parts, namely, the body part or waist (which is the
lower in the mould), and the part for forming the bottom of the pot; Figure 3 is a
section through the body part or waist of the pattern and its corresponding
moulding box, and Figure 4 is a plan of Figure 3. The section shewn by Figure 3
is not strictly a true section, some of the parts being shewn for convenience as they
would appear in a section taken somewhat on one side of the centre line of the
plan; L, L, are the two halves of the pattern which is divided vertically at its
centre, and M, M, are the two halves of the moulding box which is also divided
vertically at its centre in both cases, in the manner as is employed in the manu-
facture of oval pots, the moulding box M, M, being similar also to those employed
for making "three-legged" pots in the ordinary manner. Each half L of the
pattern is cast upon one half Ñ of a base plate, and the two half patterns L with
their corresponding half base plate N are bolted together through the snugs C, C, C,

page_text: (shewn by dotted lines on plan) with a thickness plated between them. The said
plate & projects at each side as far as the upper and lower extremities of the
moulding box, and forms the vertical division for the mould. The base plate N, N,
stands upon four feet g, g, etc (shewn by dotted lines on plan) to enable it to be
readily moved by hand. A porté D' exactly corresponding to the porté D at the
base of the hedgehog is turned at the base of the pattern L, L, to receive the two
balves M, M, of the moulding box; e, e, are the ear patterns, each pattern e being
split vertically, and one half carried on each side of the plate d as in moulding the
ears of oval pots, and as shewn on plan. The moulding box M, M, rests upon the
upper part of the plate N, N. The two halves M, M, of the moulding box are held
together by the pins O, O, passing through snugs, as shewn, whilst the mould is
being rammed up; P is a porté turned at the top of the moulding box M, M, to
receive the upper moulding box hereinafter referred to. The porté P is of course
turned concentric with the porté D¹ and the patterns. The projections 1, l, etc., are
cast out to retain the sand at the joints of the moulding box when the halves are
removed from around the pattern; ff, are snugs carrying pins to act as guides in
putting on the upper moulding box. The profile of one of the snugs with its
guide pin is shewn by dotted lines Figure 3. Q, Q, etc., are handles by which the
half moulding boxes M, M, are moved. It will be understood that each half
pattern L and half moulding box M form an exact semicircle on plan, so that when
the half moulding boxes are removed from the pattern and are put together for
casting they form an exact circle on plan.
Figure 5 is a cross section through the part of the pattern to form the bottom of
the pot and legs with the upper moulding box, and Figure 6 is a plan of the same;
R is the pattern, and r, etc., the legs which are dowelled to the pattern, and are 2
lifted off with the mould in the usual manner. The pattern R is cast upon a base
plate S, and a porté P' is turned as shown to receive the bottom of the moulding
box T. The porté P¹ exactly corresponds to the porté P at the top of the lower
. moulding box, as the moulding box T is made to fit around the porté P. The
moulding box T is similar to those used in moulding "three-legged" pots in the 3
ordinary manner. The base plate S stands upon three feet h, etc. (shewn by dotted
lines on plan) to enable it to be readily moved. The projection i, i, acts as a
support to the sand in the moulding box T when it is lifted from off the pattern.
The sougs ff, with the holes therethrough correspond to the snugs ff (Figures 3
and 4), with their guide pins upon the lower moulding box. The profile of one of 3
the snugs f¹ is shewn by dotted lines Figure 5; h, k, are snugs at the top of the
moulding box T, by means of which an upper box is fastened to the box T when
long legs are required to the pot; m, m, are handles by which the box T is lifted.
Figure 7 is a vertical section through the core and mould, and shews the boxes
put together ready for casting. The two halves of the moulding box M, M, are 4
held firmly together by the cotter pins, shewn by Figure 4, and the upper box T is
held down firmly to the lower box M. by means of the links n, n, which hang from
the handles m, m, and the lower ends of which are tapped up tightly under the
handles Q, Q. Weights o, o, hang down from the handles m, m, to which they are
hooked on, as shewn, so as to keep the boxes firmly down on to the base plate B 4
during the operation of casting. The weight on one side only is shewn for
convenience, and each weight has a handlo at the top, as shewn by which it is
lifted. U is the git into which the metal is poured, and is of the usual description.
One set of patterns and core box is sufficient for three operators, namely, for one
man who rams up the body or waist, and two boys who ram up respectively the 5
core and the part of the mould to form the bottom of the pot.
Of course the boxes and other parts are made to fit accurately in their places.
The second part of my Invention relates to stop bail handles for cast iron hollow
ware. This part of my Invention is illustrated by Figures 8 and 9, which are
respectively an elevation with the washer removed and a vertical cross section. 5
A is the lower end of one side of the bail handle, and B a plain loop formed at the
bottom thereof; C is a boss cast upon the side of the pot or other utensil, and D is

page_text: a stud cast upon the boss C; E is a piece of iron wire cast into the stud D; F is a
projecting edge cast upon the boss C, a recess being thus left between the pro-
jecting part F and the stud D to receive the loop B; G is a washer_preferably of
malleable cast iron, and is riveted firmly up (by means of the wire E) against the
stud D and the projecting part F; a is a fillet upon the washer G projecting into
the said recess, and thus effectually preventing the washer from moving out of
centre. The projecting part F and the fillet a are cut away, as shewn at H, so as
to allow the bail handle to be turned down from the vertical position, as shewn to
a horizontal position shown by dotted lines, the ends of the projecting part F
forming stops for the bail handle.
Having thus stated the nature of my said Invention, and particularly described
and ascertained the manner of performing the same, I declare that what I claim as
my Invention and desire to secure by Letters Patent is,―
1st. The method of preparing the moulds used in the manufacture of "three-
legged" pots or "negro" pots, substantially as herein described and as illustrated
by Figures 1 to 7 of the accompanying Drawings
2nd. The employment of the turned portés lettered respectively D, D', P, P¹,
with the corresponding parts formed to fit around them, substantially us and for
the purpose herein described and shewn by the Drawings.
3rd. The opening F at the top of the core box E, E, and also the employment of
the plunger J in combination with the core box E, E, and also the hedgehog A in
combination with the plate B, substantially as and for the purpose herein described
and shewn by the Drawings.
4th. Forming the pattern for the bottom of the pot in a separate piece from the
body or waist part, and ramming it up on a separate plate, substantially as herein
described and illustrated by Figures 5 and 6 of the accompanying Drawings.
5th. The improved construction of stop bail handle for cast iron hollow ware
consisting of the projecting part F which is discontinuous at H in combination
with the plain loop B, substantially as and for the purpose herein described and
illustrated by Figures 8 and 9 of the accompanying Drawings.
In witness whereof, I, the said Thomas Holcroft, have hereunto set my hand
and seal, this Twelfth day of June, in the year of our Lord One thousand
eight hundred and eighty.
Witness,
STEPHEN WATKINS,
Assoc. M. Inst., C.E.,
Office for Patents,
Wolverhampton.
THOMAS HOLCROFT. (L.s.)