IMPROVEMENTS IN MAKING MOULDS FOR CASTING, AND IN APPARATUS THEREFOR
Year: 1870

page_text: PROVISIONAL SPECIFICATION left by John Page at the Office of the
Commissioners of Patents, with his Petition, on the 12th November
1870.
I, JOHN PAGE, of Glasgow, in the County of Lanark, North Britain,
Civil Engineer, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN MAKING MOULDS FOR CASTING, AND IN APPARATUS THEREFOR,"
to be as follows, that is to say :-
This Invention has for its objects to obtain increased accuracy in
contour and in thickness, increased rapidity in moulding, and reduced
labor and cost, and is applicable in making moulds for casting pots and
other hollow ware, shell, shot, pipes, columns, and other similar articles.
In making a mould for a cast-iron pot a segmental metal pattern is
employed, which is fixed upon a spindle carried in a bracket bearing so
that it can rotate. The pattern is thickest at one end or in the middle
of the segment, and is thinned or sharpened at one or both edges so as
to cut its way into the sand or mould material, and so that the thickened
part sleeks or smoothens both the inner surface of the outer part or
mould and the outer surface of the inner part or corc. The sand for the

page_text: entire mould (including the core) is rammed into two half boxes, each
of which boxes has in connection with its half core part, and one of
these half boxes being placed in position on what may be termed the
moulding plate the segmental pattern is turned so far round as to bury
itself in the sand in that half box, after which the second half box is
placed and fixed in position on the moulding plate. The segmental
pattern is then made to rotate by means of a handle or hand wheel fixed
on its spindle, and in forcing a way for itself through the sand forms all
the mould surfaces excepting those for the feet and handles, which are
shaped separately in the ordinary way. The pattern spindle is made
hollow, and the usual blackening powder or black wash is blown down
it and into the mould whilst the pattern is rotating, so that the mould
surfaces are formed, sleeked, and finished all at one operation. A flange
is formed on the part of the pattern corresponding to the edge of the pot
and at right angles to the axis, and this shapes a flat annular space in the
mould, the sides of which space are to constitute the parting surfaces of
the mould or outer part and the core part. The moulding plate differs
from the plate on which the boxes are placed for casting by the part
supporting the core part being as much higher in the casting plate as
is equal to the thickness of the flange on the pattern, so that the space
becomes closed when the boxes are put on the casting plate.
The arrangements for making moulds for shell and various other
articles are similar, being of course modified to suit the form or pecu-
liarities of each article. The segmental pattern may be arranged to be
turned by power when the size of the article makes it desirable, and the
sand or mould material may be compressed in the boxes by ramming
machinery or by hydraulic apparatus such as is in use or has been
proposed for that purpose. In some cases, as in making moulds for
pipes or cylinders for example, the pattern may be a complete cylinder
instead of a segment, one part being of a thickness corresponding to the
intended thickness of the finished article whilst the remainder is thinner.
The sand is rammed inside and outside of the pattern, which is then
made to rotate, and shapes the surfaces to their finished condition,
compressing and sleeking them at the same time.