IMPROVEMENTS İN MEANS OR APPARATUS EMPLOYED IN THE MANUFACTURE OF PAPER.
Year: 1873

page_text: LETTERS PATENT to George Tidcombe, the younger, of the Firm of
George Tidcombe and Son, of Watford, in the County of Herts;
Paper Makers' Engineers, for the Invention of
IMPROVEMENTS İN
MEANS OR APPARATUS EMPLOYED IN THE MANUFACTURE OF PAPER.'
PROVISIONAL SPECIFICATION left by the said George Tidcombe at
the Office of the Commissioners of Patents, with his Petition, on
the 23rd July 1873.
I, GEORGE TIDCOMBE, the younger, of the Firm of George Tidcombe
5 and Son, of Watford, in the County of Herts, Paper Makers' Engineers,
do hereby declare the nature of the said Invention for "IMPROVEMENTS
IN MEANS OR APPARATUS EMPLOYED IN THE MANUFACTURE OF PAPER," to be as
follows:-.
In apparatus employed in the manufacture of paper there are used
what are called strainers or knotters formed of plates or surfaces of
metal with fine slits in them, through which the straining is effected.
These plates are ordinarily formed of a mixed metal, such as gun metal

page_text: or Muntz metal, and they are produced either by casting them in the
form desired and then producing the finer parts of the openings by saw
cuts, or they are cast in ingots, which are simply rolled to the desired
thickness and then cut for the desired openings larger on one side but
with fine slits on the other or upper side or surface.
Such plates so produced soon become so much destroyed as to require
to be replaced.
I have found that by employing for such plates copper unmixed or
mixed only to a very slight degree with other metal, and by smoothing
or reducing that surface of the metal of the ingot which is to form the
upper surface of the finished plate before such ingot is subjected to the
rolling process, a tougher and better and much more durable surface is
obtained and preserved to the finished plate.
In the cutting of the grooves on the under side of the plates the teeth
of the cutters are formed pointed and inclined at the cutting edge
thereof, outward from a radial line so as to clear better, and the cutters
are driven at a much slower speed than heretofore, say at a surface speed
of about 200 feet per minute, with a corresponding reduction in the
speed of the cutting surface of the saw employed in cutting the slits;
and the cutting is facilitated by the use of a solution of soft soap and
water or other suitable lubricant.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said George Tidcombe in the Great Seal Patent Office
on the 23rd January 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE 2
TIDCOMBE, the younger, of the Firm of George Tidcombe and Son,
of Watford, in the County of Herts, Paper Makers' Engineers, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent bearing date the Twenty-third day of July, in the year 3
of our Lord One thousand eight hundred and seventy-three, in the
thirty-seventh year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said George Tidcombe, the younger,

page_text: Her special license that I, the said George Tidcombe, the younger,
my executors, administrators, and assigns, or such others as I, the
said George Tidcombe, the younger, my executors, administrators,
and assigns, should at any time agree with, and no others, from time
to time and at all times thereafter during the term therein expressed
should and lawfully might make, use, exercise, and vend, within the
United Kingdom of Great Britain and Ireland, the Channel Islands,
and Isle of Man, an Invention for "IMPROVEMENTS IN MEANS OR APPARATUS
EMPLOYED IN THE MANUFACTURE OF PAPER," upon the condition (amongst
others) that I, the said George Tidcombe, the younger, my executors
or administrators, by an instrument in writing under my or their,
or one of their hands and seals, should particularly describe and
ascertain the nature of the said Invention, and in what manner the
same was to be performed, and cause the same to be filed in the Great
Seal Patent Office within six calendar months next and immediately
after the date of the said Letters Patent.
NOW KNOW YE, that I, the said George Tidcombe, the younger,
do hereby declare the nature of the said Invention, and in what
manner the same is to be performed, to be particularly described and
ascertained in and by the following statement thereof, that is to
say :-
In apparatus employed in the manufacture of paper there are used
what are called strainers or knotters formed of plates or surfaces of
metal with fine slits in them, through which the straining is effected.
These plates are ordinarily formed of a mixed metal, such as gun metal
or Muntz metal, and they are produced either by casting them in the
form desired and then producing the finer parts of the openings by saw
cuts, or they are cast in ingots, which are simply rolled to the desired
thickness and then cut for the desired openings larger on one side but
with fine slits on the other or upper side or surface.
Such plates so produced soon become so much destroyed as to require
to be replaced.
I have found that by employing for such plates copper unmixed or
mixed only to a very slight degree with other metal, and by smoothing
or reducing that surface of the metal of the ingot which is to form the
upper surface of the finished plate before such ingot is subjected to the

page_text: rolling process, a tougher and much more durable surface is obtained
and preserved to the finished plate.
For the cutting of the grooves on the under side of the plates the
teeth of the cutters are formed pointed and inclined at the cutting edge
thereof outward from a radial line so as to clear better with the incli- 5
nation of the cutting edges of the respective teeth formed alternately in
opposite directions, and the distance from the point of one tooth to that
of the next, say at least half an inch, and the cutters are driven at a
much slower speed than heretofore, say at a surface speed of about
200 feet per minute, with a corresponding reduction in the speed of the 1
cutting surface of the saw employed in cutting the slits. The cutting is
also facilitated by the use of a solution of soft soap and water or other
suitable lubricant.
Having thus described my Invention and means which I adopt in
carrying the same into effect, I would have it understood that what I 1
claim is, the improvements in the manufacture of strainer or knotter
plates used in the manufacture of paper, substantially as described.
In witness whereof, I, the said George Tidcombe, the younger,
have hereunto set my hand and seal, this Twenty-third day of
January, in the year of our Lord One thousand eight hundred 20
and seventy-four.
MTD CAUTT TNR