Year: 1887

page_text: Date of Application, 15th Mar., 1887
Complete Left, 1st Dec., 1887
Complete Accepted, 6th Jan., 1888
1, THOMAS WILLIAMSON of 5 Severn Street, Middlesborough in the county of York,
Shipwright do hereby declare the nature of this invention to be as follows:-
This is a hand instrument of the tongs or pincer type having two handles or levers
jointed together and to a gripping plate near the working end. The gripping plate
is a bent piece of metal the working face being approximately at right angles to the
longitudinal axis of the levers. Upon the inner face of the gripping plate is an
octagonal or other shaped hard steel plate secured to the gripping plate by a thumb
screw or other means whereby it can be turned so as to present any one of its edges or
working faces to the tooth of the saw and may be fixed so. The handle which while in
use is generally the upper one has a broad and flattened end which bears upon the
Hat of the saw when in use. The working end of the other or lower handle passes
through an opening in the upper handle and ends in a hard nose. In use the gripping
plate is placed over the toothed edge of the saw and the octagonal plate adjusted with
that edge or face in working position which is most suited to the kind of tooth to be
set, each face of this plate being preferably bevelled to a different size or angle. The
handles are now closed together with the effect that while the broad end of the upper
handle holds the saw firmly against the gripping or octagonal plate, the nose of the
lower handle forces the tooth against the bevelled edge of the octagonal plate thus
imparting to it the requisite set.

page_text: I, THOMAS WILLIAMSON of 5 Severn Street, Middlesborough in the County of York,
do hereby declare the nature of this invention and in what manner the same is to be
performed to be particularly described and ascertained in and by the following
statement:
This is a hand instrument of the tongs or pincer type having two handles or levers
jointed together and to a gripping plate the point of junction being near the working
ends of the levers.
The gripping plate is a bent piece of metal the working face being approximately
at right angles to the line bisecting the angle formed by the working ends of the
lovers.
Upon the inner face of the gripping plate is a polygonal steel plate secured to the
gripping plate by a thumb screw or other means permitting it to be turned so as
to place any one of its edges parallel with the serrated edge of the saw. The
metal along each side of the polygonal plate is cut or ground away so as to form
a facet each facet being at a different angle to the surface of the plate, and the
different facets serve as guages or templets to limit the amount of set imparted to the
teeth of the saw.
The handle which while in use is generally the upper one has a broad and
flattened end which when in use bears upon the flat or blade of the saw. The
working end of the other or lowor handle passes upwards through an opening in
the upper handle and terminates in a hard nose which in operation bears against
the tooth.
In use the gripping plate is placed over the toothed edge of the saw and the poly-
gonal setting guage adjusted with that one of its faces parallel to the saw teeth which
is most suited to the kind of tooth to be set.
In the accompanying drawing
Fig. 1 is an elevation partly in section, of the saw set, the section being taken
through the line xz, in fig. 2 which is a plan thereof. Fig. 3 is a detail of the bevilled
plate or setting guage.
A is the gripping plate or frame, a portion of which is cut away between the
parts A' these parts being bent at right angles to the gripping part A. and
serving as points of attachment for lugs B through which passes a pin or fulcrum
bolt C. On this bolt are fulcrummed the two levers D and D the former of
which is bifurcated or divided into two branches d at its working end, the end faces
of the branches being flattened so as to afford a large bearing surface against the
saw E.
The lever D' is mounted between the branches d of the lever D and terminates at
its working end in a nose d' the area of which is about sufficient to cover the tooth of
a saw such as the instrument is adapted for setting.
To the inner face of the plate A is secured the setting guage or templet Fa front
view of which is shown in fig. 3. This guage consists of a polygonal plate of
hardened steel and the metal at each side is cut or ground away so as to form flat
facets ƒ of different bevils or angles, the different angles corresponding to the
different degrees or amounts of "set" which are commonly imparted to saw teeth.
The guage is attached to the plate A by the thumb nut G and by slackening this nut
the guage may be turned round so as to bring any desired edge opposite to the

page_text: nose 2 this being done the nut is again tightened and the apparatus is ready for use
as follows.
In figure have shown front and side views of another form of guage or
setting plate F which in some cases is preferable to the polygonal form shown in the
preceding figures. This plate is taper or wedge shaped and has two bevelled facets f¹
formed at each end, one on each face of the plate. The bevils at the thin end of the
plate are adapted for thick saws and the tapering form of the plate compensates for
the varying thicknesses of saws and allows for the uniform closing of the ends d of
the lever D. The plate is secured by the thumb nut G from which it has to be
entirely removed when it is desirable to change the setting facet for one on the opposite
side of the plate.
The saw E is placed on a suitable support with the serrated edge upwards. The
levers D and D are then grasped in one hand and the operator adjusts the face of the
guage F flat against the blade of the saw with the other hand. This is readily effected
the plate A not being rigidly connected to either of the levers D and D' which is the
case in some instruments constructed for this purpose. The levers are then closed
with the force requisite to bend or set the tooth and as soon as this movement
commences the ends of the branches d close upon the blade of the saw and press it
firmly against the face of the plate F whilst the nose de presses the tooth against the
bevelled edge or facet and sets it.
The most important feature of this invention is the manner in which the force
exerted in compressing the levers is distributed or applied to opposite parts of the
plate (which may be regarded for the purpose of explanation as being integral with
the plate A), for the purpose of counteracting each other. C being the fulcrum of
the levers D and D₁ and c the line therefrom perpendicular to the surface of the
plate it will be noticed that the pressure of the levers is exerted on both sides of
this line so that the forces oppose and neutralize each other and the saw E being
firmly clamped between the frame and the ends of the levers cannot be bent or buckled,
neither can it spring towards the operator nor can the nose d² slip over the tooth
but must exert a dead pressure thereon and therefore the tooth is bent at the
root or broadest part and the whole of the tooth is "set" and not merely the
point thereof.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is
1. In a saw set the combination with a clamping plate such as A of two levers D
and D both of which are pivotted to or upon the plate, one of them being adapted at
its working end to press the blade of the saw firmly against the plate and the other to
bear against and set the teeth of the saw substantially as described and illustrated in
the accompanying drawings.
2. In a saw set the combination with a clamping plate such as A and two levers D
and D' pivotted to or upon that plate of a polygonal setting plate or guage such as F
having flat facets formed at various angles substantially as described and illustrated
in the accompanying drawings.
3. In a saw set, a setting plate or guage such as F' consisting of a taper or wedge
shaped plate having bevelled facets formed at the ends substantially as described
and illustrated in figuro 4 of the accompanying drawings.
Dated this 5th day of December 1887.
THOMAS WILLIAMSON.