IMPROVED MACHINERY FOR GRINDING HAND SAWS
Year: 1870

page_text: LETTERS PATENT to William Edward Newton, of the Office for
Patents, 66, Chancery Lane, in the County of Middlesex, Civil
Engineer, for the Invention of "IMPROVED MACHINERY FOR GRINDING
HAND SAWS." -A communication from abroad by William Finley
Semple, of Mount Vernon, in the State of Ohio, United States of..
America.
Sealed the 19th August 1870, and dated the 23rd May 1870.
PROVISIONAL SPECIFICATION left by the said William Edward
Newton at the Office of the Commissioners of Patents, with his
Petition, on the 23rd May 1870.
I, WILLIAM.EDWARD NEWTON, of the Office for Patents, 66, Chancery
Lane, in the County of Middlesex, Civil Engineer, do hereby declare
the nature of the said Invention for "IMPROVED MACHINERY FOR GRINDING
HAND SAWS," to be as follows:-
This Invention consists in an arrangement of parts whereby the saw..
blades to be ground are made to occupy a crosswise position on a.

page_text: *revolving table with the backs of the saws lying nearest to the periphery
of the table; and with the blades set inclining on their back edges
elevated relatively to the face of the table, and the saws thus arranged
and set are made to sweep across the face of a revolving grindstone,
whereby the necessary reduction is secured and the stone kept true by
reason of the saws having a prolonged sweep over the stone at those
parts or portions where the greatest reduction is required to be made.
The machine consists of a framing constructed to support two shafts
which may rest in pedestals or steps. One of these shafts carries the
grindstone and the other shaft the table that carries the saws or chucks
in which the saws are secured. The shafts are belted or otherwise
driven so as to give motion to the table and grindstone, and the table
and stone are so disposed that they sweep the one over or under the
other. The revolving table. may be made of iron and the chucks
formed of iron slabs arranged crosswise on the face of the table and
secured thereon by bolts. These chucks have the saw blades secured
within them by means of steel slips, fitted to the slabs, and arranged so
as to leave seats for the saws between them. These slips are of a wedge
shape so that the saw blades may be easily secured in their places by
sliding them into their seats between the slips until their cutting edges
and backs come in contact with the slips. The slips should be no
thicker than the cutting edge and back of the finished saw, and they
may either be fixed or adjustable on the chucks, and they are hardened
to a tool temper and bevilled off on their inner edges from beneath,
leaving sharp elevated edges projecting half way up or thereabouts the
thickness of the teeth on the cutting edge of the saw, and proportionately
elevated on the rear edge thereof. Thus constructed the strips serve
effectually to hold the saw blades in their places by reason of the blades
being a little softer than the steel slips, which causes the latter on
tapping with a hammer on the heels of the blades to indent themselves
into the edges of the saws or teeth thereof. A button may also be
arranged on the back end of either chuck so that on being turned up
against the heel of the saw it restrains the latter from backing out of its
scat. The backs of the saw blades are all turned outwards towards the
periphery of the revolving table, the heel portions of the backs lying in
closest proximity to said periphery. This is important, and forms a
leading feature of the Invention, that secures the grinding surface of the

page_text: stone being kept true. Thus it is from the back of the saw that tlio:
most steel has to be removed, consequently that part of the blade
which requires to be most reduced should have the longest or greatest.
sweep over the surface of the stone.
SPECIFICATION in pursuance of the conditions of the Letters Patent;
filed by the said William Edward Newton in the Great Seal Patent
Office on the 19th November 1870.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
EDWARD NEWTON, of the Office for Patents, 66, Chancery Lane, in the
County of Middlesex, Civil Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-third day of May, in the year
of our Lord One thousand eight hundred and seventy, in the thirty-third
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said William Edward Newton, Her special licence,
that I, the said William Edward Newton, my executors, administrators,
and assigns, or such others as I, the said William Edward Newton, 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 "IMPROVED
MACHINERY FOR GRINDING HAND SAWS," being a communication to me from
abroad by William Finley Semple, of Mount Vernon, in the State of
Ohio, United States of America, upon the condition (amongst others)
that I, the said William Edward Newton, my executors or adminis-
trators, 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 William Edward Newton; do hereby.
declare the nature of the said Invention, and in what manner the same-

page_text: is to be performed, to be particularly described and ascertained in and
by the following statement, reference being had to the Drawing here-
unto annexed, and to the letters and figures marked thercon (that is to
say) :-
In explanation of the object of this Invention it may be observed that
a perfect hand saw should have its cutting or toothed edge exactly of
the same thickness from heel to point, and that it should taper with a
true bevil from the cutting or toothed edge to its back, leaving the back
at the heel slightly thinner, preferably about one-fortieth part of an
inch, than the cutting edge. A thick or thin spot in the blade interferes
with the true bevil or taper, thereby rendering the saw defective, and it
is such irregularities that necessitate the setting of the teeth, even when
the saw is designed to be used for cutting up dry lumber, whereas a
hand saw having a perfectly true taper requires no set in its teeth for
sawing dry lumber. There has heretofore been great difficulty, however,
in obtaining such a true taper; this may be explained by stating that in
the manufacture of hand saws, when cut out, toothed, tempered, and
hammered ready for grinding the steel is of equal thickness throughout
the blade, hence the further the distance from the cutting edge the
greater the quantity of steel necessary to be removed in order to give
the desired taper to the blade, and the greater the wear upon the
grinding surface which has this additional lábor to do. As the saw also
varies in width from the heel to the point, there is a further difficulty in
the way of securing the desired taper, and in view of these difficulties,
the impossibility which has heretofore been experienced of keeping the
grinding surface true will be readily understood, the labor to be per-
formed being unequally distributed, and without the grinding surface
can be kept true it is not practicable to effect a perfect reduction of the
blade of the saw; but if the surface of the grinding stone be true (or in
the case of any irregularity the operation of grinding has the effect of
truing such surface) then the result sought to be attained is secured.
This the present Invention accomplishes, and to this end the Invention
consists in a combination and arrangement of parts or devices whereby
the saw blades to be ground are made to occupy a crosswise position on
a revolving table, with the backs of the saws lying nearest to the
periphery of the table and with the blades set inclining or their back-edges
elevated relatively to the face of the table. The saws thus arranged and
set are made to sweep across the face of a revolving grindstone, whereby

page_text: the necessary reduction is secured, and the stone is kept truc by reason of
the saws having a prolonged sweep over the stone at those parts or
portions where the greatest reduction is required to be made.
In the accompanying Drawing Fig. 1 represents a sectional elevation
of a machine constructed in accordance with the Invention with saw
blades thereon as exposed to the action of being ground; Fig. 2 is a
plan of the same; and Fig. 3 a rear view on an enlarged scale of one
of the chucks as secured to a revolving table, and with a saw in its
place.
The frame A of the machine is constructed to support two shafts
B and C, which may rest in pedestals or steps D, E. The one B of these
shafts carries the grindstone F, and the other shaft C the table G that
carries the saws H or chucks I in which the saws are secured. The
shafts B and C are belted or otherwise driven so as to give motion to the
table G and grindstone F, as indicated by their respective arrows in
Fig. 2, and the table and stone are so disposed that they sweep the one
over or under the other, as clearly seen in Fig. 1. The revolving table G
may be made of iron, and the chucks I formed of iron slabs arranged
crosswise on the face of the table, and secured thereon by bolts. These
chucks I have the saw blades H secured within them by means of steel
slips J fitted to the slabs and arranged so as to leave seats for the saws
between them. These slips are of a wedge shape, so that the saw blades
may be easily secured in their places by sliding them into their seats
between the slips J until their cutting edges and backs come in
contact with the slips, and afterwards slightly tapping with a hammer
against the edges of the heels of the blades. It is necessary that the
slips J should be no thicker than the cutting edge and back of the
finished saw, and they may either be fixed or adjustable on the chucks;
and they are hardened to a tool temper and bevilled off on their inner
edges from beneath, leaving sharp elevated edges projecting half way up
or thereabouts the thickness of the teeth on the cutting edge of the saw,
and proportionately clevated on the rear edge thereof. Thus constructed
the strips serve effectually to hold the saw blades in their places by
reason of the blades being a little softer than the steel slips which causes
the latter on tapping with a hammer on the heels of the blades to indent
themselves into the edges of the saws or teeth thereof. A button b may
also be arranged on the back end of either chuck, so that on being

page_text: turned up against the heel of the saw it restrains the latter from backing
out of its seat.
The backs of the saw blades are all turned outwards towards the
periphery of the revolving table G, the heel portions of the backs lying
in closest proximity to this periphery. This is important, and forms a
leading feature of the Invention, and secures the grinding surface of the
stone being kept true. Thus it is from the back of the saw that the
most steel has to be removed, consequently that part of the blade which
requires to be most reduced should have the longest or greatest sweep
over the surface of the stone. The chucks I must have their sides or
edges (nearest to the periphery of the table) elevated to an extent
proportionate with the amount of steel it is required to grind away
before the cutting edges of the saws come in contact with the stone;
this is done by slipping a packing strip c under the outer edge of either
chuck, and then bolting down the chuck to the table. After the one
side or face of the saws has been ground as required the saws or blades
are reversed for similar operation on their opposite sides or faces,
packing strips c of double the thickness of those previously used being
introduced under the outer edges of the chucks to provide for the
reduction made from the sides previously ground, and so that a like
reduction may be made on both sides of the saws. The angular position
of the saws on the revolving table or in the chucks thereon, and crosswise
arrangement of the saws relatively to the face of the table with their
backs lying outwards towards the periphery of the table, are essential
elements of the Invention. It is desirable to have the stone and table
travel at different velocities to prevent the saws while being ground
from coming repeatedly upon the same parts in the grinding face or
surface of the stone. The table G is made capable of being raised
or lowered so as to bring the saws on the chucks in or relieve them
from contact as required with the stone, as, for instance, by nuts and
screws d, d, applied to the step E of the shaft C.
Having now described the Invention, which has been communicated
to me by my foreign correspondent, and having explained the manner
of carrying the same into effect, I claim as the Invention secured to me
by Letters Patent as aforesaid,-
First. The arrangement of parts whereby the saw or saws is or are
placed in a crosswise position over the face of the revolving table which

page_text: carries them, so that their backs lie next to the periphery of the table
for operation in combination with a grindstone arranged to overlap the
face of the table and made to rotate in relation to the latter as hercin
set forth.
Second. The combination of the angularly adjustable chucks I and
their saw holding strips J with the revolving table G, and grindstone F
as and for the purpose or purposes herein set forth.
In witness whereof, I, the said William Edward Newton, have
hereunto set my hand and seal, the Eighteenth day of November,
in the year of our Lord One thousand eight hundred and seventy:
W. E. NEWTON. (L.S.)