IMPROVE MENTS IN SAWING AND CUTTING WOOD
Year: 1849

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY
FRANCIS, of Chelsea, in the County of Middlesex, Engineer, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Fourth day of January,
One thousand eight hundred and forty-nine, in the twelfth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
Henry Francis, my exors, adññors, and assigns, Her especial license, full
power, sole privilege and authority, that I, the said Henry Francis, my
exors, adñiors, and assigns, or such others as I, the said Henry Francis,
my exors, aditiors, or assigns, should at any time agree with, and no others,
from time to time and at all times during the term of years therein expressed.
should and lawfully might make, use, exercise, and vend, within England,
Wales, and the Town of Berwick-upon-Tweed, my Invention of "IMPROVE
MENTS IN SAWING AND CUTTING WOOD;" in which said Letters Patent is con-
tained a proviso that I, the said Henry Francis, shall cause a particular
description of the nature of my said Invention, and in what manner the same
is to be performed, by an instrument in writing under my hand and seal, to be
inrolled in Her said Majesty's High Court of Chancery, within six calendar
months next and immediately after the date of the said in part recited Letters
Patent, as in and by the same, reference being thereunto had, will more fully
and at large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
Henry Francis, do hereby declare that the nature of my said Invention, and
the manner in which the same is to be performed, are fully described and
ascertained in and by the following statement thereof, that is to say :-
The first part of my Invention consists of improvements in the construction
and use of saws, so as to improve and facilitate their cutting wood. Hereto-
fore saws have usually consisted each of a series of teeth, and the teeth of a
saw have each been alike, and they have been bent in alternate directions.
The consequence of this construction has been, that the wood cut thereby has
had larger or smaller saw cuts on the surfaces according to the teeth used.
These observations apply to saws generally, both straight and circular. Now
according to this part of my Invention I cause the teeth to be combined with
what I call cutters; and I usually make the cutters to alternate with tho
teeth, so that a tooth follows a cutter in regular succession, though this
arrangement may be varied. The teeth are to be of any of the ordinary
constructions, according to the class of saw which is to be made according to
my Invention; and the cutters I make by preference of the shape of what are
called "flem teeth, that is, they are not hooked or under cut, but incline both
ways. I cause the cutters to be bent alternately on either sides in like
manner to what the teeth of saws have heretofore been bent, but the teeth are
left unbent, by which. means the cutters make a cut on either side, and the
teeth remove the wood between the cuts. It is of great importance that the
cutters on either side should follow one another with accuracy, in order that
the cut mado on either side may be smooth and truc, and that the two cuts
should be parallel; and for this purpose I fix a file in a flat block, the file
being at one edge thercof, and at a distance below the general surface of the
block, equal to that to which the cutters of a saw are bent, such block being
eight or ten inches long and three or four inches wide. By means of this
instrument I am enabled to make the projecting cutters on either side correct,
and so as to follow each other in the same line. The flat block when used
rests on the surface of the saw, and it is to be moved to and fro; so that the
file will come against the cutters, and thus will the cutters be filed away at
the outer sides of the points till they are all sharp and range correctly onc
after the other. This block will also be found useful when sharpening saws of
the ordinary construction, and forms part of my Invention. In using these
saws in saw mills, in place of causing them to move up and down vertically, or
at right angles to the surface of the wood as heretofore, I find that a better
cut may be made and with less power by having the saw gate so arranged as
to move in an inclined position; and generally I have found it best to cause

page_text: the saw gate to move at an inclination of about sixty-seven degrees to the
surface of the wood; but I do not confine myself to that angle; and I would
state that this part of my Invention is also applicable when using saws of the
ordinary construction. And although I prefer, when using saw mill saws
made with cutters according to this part of my Invention in gates which
move up and down in an inclined position, yet they will be found to produce
superior work to ordinary saws when working in a vertical position. In
cutting off thin surfaces of wood with my improved saws, I prefer to employ
a smooth metal plate or fixed table, with a transverse slit or opening, the metal
on the sides of the opening being formed to an inclination. The wood is to be
caused to move or slide longitudinally on this plate, and the saw used (which is
to be straight) is to be inclined, so as to be parallel with the opening through
the plate, and the edge of the saw is to protrude a distance (in a direction to
meet the moving wood) according to the thickness of wood to be cut off.
A quick reciprocating motion is to be given to the saw as the wood moves
forward on the bed plate, and the portion cut off will descend through the
plate in like manner to a shaving in a plane. I would remark, that although
I prefer to use my improved saws for this part of my Invention, yet other saws
may be employed.
The second part of my Invention relates to improvements in mounting saw
gates, which I prefer to be inclined in place of vertical, and consists of
employing springs; and I form the springs of such strength that they will lift
the saw gate, by which means I find that the working is improved. I would
remark, in respect to this part of my Invention, that I am aware that saws not
in gates have before had springs for lifting them. I do not claim the same,
this part of my Invention being confined to saw gates.
I will now describe the third part of my Invention, which is applicable to
the sawing of wood into planks and boards from timber of irregular sides, in
order to avoid shaping the timber first before it is fixed in a mill; and it also
consists of guiding each saw so as to ensure the several saws stretched in a saw
gate to cut parallel boards or planks in place of depending on the great tension
now resorted to for preventing the saws being led away by knots or inequalities
of the wood. In carrying out this part of my Invention, I cause a plate of
wood to be fixed to the irregular surface of a log of wood, the outer surface of
such fixed piece being true, and caused to move against a guide piece in the
mill so as to cause the log to pass through the mill truly, notwithstanding the
irregularity of its side or sides; and thus will the boards or planks cut off be
parallel; and in order to ensure this I fix a bar of hard wood across the saw
mill, having slits cut in the same at the intervals apart at which it is desired

page_text: the boards or planks should be cut, and this bar is to be so fixed that the
backs of the several saws shall enter the cuts and move up and down in them,
and be guided truly by them.
In witness whereof, I, the said Henry Francis, have hereunto set
my hands and seal, this Third day of July, in the year of our 5
Lord One thousand eight hundred and forty-nine.
HENRY (Ls.) FRANCIS.
AND BE IT REMEMBERED, that on the Third day of July, in the
year of our Lord 1849, the aforesaid Henry Francis came before our
said Lady the Queen in Her Chancery, and acknowledged the Specification
aforesaid, and all and every thing therein contained and specified, in form
above written. And also the Specification aforesaid was stamped according
to the tenor of the Statute made for that purpose.
Enrolled the Fourth day of July, in the year of our Lord One thousand
eight hundred and forty-nine.