Year: 1899

page_text: I, PATRICK FRANCIES MCDONALD, residing at No. 615, Monroe Avenue, Scran-
ton, Lackawanna County, Pennsylvania, one of the United States of America,
Miner, 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:-
-
Referring to the accompanying drawings and to letters or figures of reference
marked thereon, which form part of this specification,
Fig. 1 of the drawings is a plan view of the invention;
Fig. 2 is a front elevation of the invention;
Fig. 3 is a section on the line xx, Fig. 1;
Fig. 4 is an enlarged detail view of the saw-guide;
Figs. 5 and 6 are detail views of the set-slide.
This invention has relation to miter boxes or machines, and is designed to pro-
vide a device of this character by means of which a double-miter cut, or a
cut having a miter in two different planes of any desired angularity, may be
accurately formed, also by means of which a single-miter cut only in either one
of two planes and of any desired angularity may be accurately formed.
The invention also involves means for readily effecting calculations which are
incident to the use of machines of this kind and to various branches of the
carpenters' art which have reference to relativo angular and circular values an⋅l
measurements.
With these objects in view my invention consists in the novel construction and
combination of parts, all as hereinafter described, and pointed out in the
appended claims.
Referring to the accompanying drawings, the letter A indicates a suitable base
whose upper surface is divided by scale-marks into two squares 1 and 2, the sides
These
of which are twelve inches in length and which has the side a in common.
scales are suitably marked in feet and inches, as shown in the drawings.
Inscribed in these squares from the point a¹ at the rear extremity of the side a
as a center and with one quadrant in each of the squares 1 and 2 is a semicircular
arc B, which is accurately divided and marked in degrees, as shown. The radius
of this are is the length of a side of the squares.

page_text: C designates a vertically-slotted center post or standard formed with a half-
ball at its lower end, which bears neatly but loosely in a hemispherical cup C
in the base A, the center point of said cup and of the bearing of the ball c coin-
ciding with the point a¹, which as before stated, is the center from which the
arc B is struck. The material of the post adjacent to the ball is cut away, as
indicated at d, to permit the post to be moved to an angle of or approaching
forty-five degrees without contacting with the base. The upper end of the post
is formed with a guide portion f, which projects through the space formed
between parallel back plates EE, whose upper and outer edges are cut to form an
arc of one hundred and eighty degrees of the same radius as the are B and
having the same center. These side plates are shown as being cut away at their
central portion to permit the post or standard to assume an inclined position to
forty-five degrees upon either side of center. These plates are preferably of
thin character and are reinforced by intermediate pieces F, of wood, as shown.
in order to provide a secure back bearing or rest for the work. These pieces F
are provided with the sliding sections F1 at their inner portions, which when
extended. as shown. increase the extent of the bearing for the work, but which
are moved back to the position indicated in dotted lines when the post or standard
is moved to an inclined position approaching forty-five degrees.
The sliding sections F1 are worked by hand and slide in recesses F2 of the
blocks F. Each section F¹ has secured to each side thereof triangular ribs or
plate-sections F3 in the same planes as the plates EE, and the rear edges f of
which ribs abut against and are stopped by said plates when the sliding
sections F1 are. pushed back.
The upper portion of the post or standard is provided with a guide which
engages the under side of the arcuate rim portions of the plates E E, as shown.
A nut G¹ engages the threaded upper end of the stud portion f and provides
means for securing the post in any desired position of adjustment. Said 'rim por-
tion is marked with a scale S in degrees, as shown. Adjustably secured to the
said post by a set-screw h, engaging a groove h¹, or by any other suitable means,
is a saw-guide H, consisting of two parallel plates, which pass through the slot of
the post and are formed with the semicylindrical sleeve portions h², which embrace
the post. They are also provided with the separated lips / at the bottom, which
protect the set of the saw-teeth.
'
I designates a horizontal radial arm or rod which is pivotally secured within a
vertical slot in the lower portion of the post, as shown. and adapted to sweep
over the base A and its inscribed arc B. Said arm or rod carries a slide I', pro-
vided with a set-screw i, by means of which it may be secured in the desired
angular or longitudinal adjustment on said rod or arm. Said slide is also pro-
vided with a stud 23, adapted to engage an aperture j, formed in a set-slide J.
The latter is formed with an edge groove j¹, which engages a lip a³ on the edge
of the base A. and also with a set screw 2, which passes through a longitudinal
slot a in said lip a³. By these means the slide J may be moved to any point on
the edge of the Ease and secured at that point. The stud is then engaged with
the aperture and the slide I¹ secured by tightening its screw i. The slide J
is preferably formed with two of the apertures j, one upon each side of the center.
in order to receive the stud when the rod or arm I is moved to either side of the
dividing-line between the two squares.
K designates an indicating wire or cord which is connected at one end to a
ring K¹, loosely mounted on the reduced base portion id of the post, so that the 5
wire may be moved to any radial position on the are B over the scale around the
squares.
at
L designates a work support or rest which is secured to supporting-block
the rear side of the base, with its rear edge against the back plate. This bar
is of wood and is designed to be secured to the block in any manner suitable to 5
permit its being removed and replaced whenever necessary.

page_text: I have shown the back plates as connected to the base by means of hinges M,
which permit it to be folded over onto the 'base when the "work-support 'L'is
removed. The latter normally holds the plates in upright position against move-
ment in one direction, and suitable back stops are provided to hold them
against movement in the opposite direction.
The operation of the machine will be readily understood. The ball-bearing
of the post permits its rotary movement to give the saw guide an angular direction
at any degree on the arc B and also an angular movement to incline said guid
at any angle from ninety to forty-five degrees in each direction to the plane of
the base. It will be readily seen, therefore, that I am able to make a compoundi
or double-miter cut by reason of these two movements and that by a proper
relative adjustment of such movement the angularity of this cut with respect to
either one of two planes may be controlled. It will at once be appreciated that
by reason of this fact the machine is of very great value for use in a great
variety of special work where angular joints of peculiar form are to be made as
well as for ordinary work, both cuts being made at the same time, and inasmuch
as by moving the post to the one side or the other of its vertical position and by
rotating it to bring the guide to either side of the line dividing the two squares
on the base the direction of angularity may be reversed. The number of pos-
sible combinations and the corresponding different cuts which may be made is
almost unlimited.
The angular adjustment of the post can be readily determined by the scale S
and its rotary adjustment by the scale on the arc B. For greater accuracy,
however, I provide the indicator wire or cord above described. In setting the
saw-guide this wire is carried to a radial position such that it exactly coincides
with the mark on the scale B which denotes the desired angle. The set-slide J
is then moved to a position where the said wire or cord crosses the center of the
aperture j, in which the stud of the slide I is to be engaged. The slide
then secured in this position. The stud is next engaged with the aperture j,
and the slide I is secured by its screw. This insures the correct position of the
saw-guide, the angular adjustment of the post being secured by its nut. The
slide I being both longitudinally and angularly adjustable on the rod or arm I,
it follows that its adjustment will correspond perfectly with the two movements
of the post.
is
The saw-guide can be adjusted vertically on the post to suit the particular
work being done.
It will also be observed that the scales on the base of the board indicate in
feet and inches or fractions thereof the value of the tangent of any given angle
on the arc B between forty-five and ninety degrees. Therefore if, either. the angle
or the value of its tangent be known the value of the other element is at once indi-
cated without calculation. To illustrate: Supposing it to be required to fit a pair
of rafters to give a particular roof a pitch of four inches to the foot, the set-slide.)
is moved to a position on the base where the center of its aperture ; is 'directly
over the four-inch mark of the scale. This at once gives the proper angle for
cutting the rafters and sets the saw-guide at that angle. This, however, is but
one instance of many similar calculations based on the relative mathematical
relations existing between a given square and a circle whose radius is equal to the
side of such square. The arrangement described, however, is not limited to cal-
culations based on a circle whose radius is twelve inches, since by the use of a
sliding scale T, placed on one of the squares 1 and 2 on the base, similar calcu-
lations may be made based on a circle of a less radius, and by extending the length
of the indicating cord or wire to any point outside the base it will be readily seen
that other calculations based upon circles of longer radii may be made.
I do not wish to limit myself to the particular construction and arrangement
of parts which I have herein shown and described, as it is obvious that many
changes may be made without departing from the spirit and scope of my invention.

page_text: 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 miter box or machine, the combination with a base, a support having
a hemispherical socket, of a saw-guide-carrying post having a ball end bearing in
said socket, and means for guiding and holding the upper end portion of said
post, substantially as specified.
2. In a miter box or machine, a base or support having a bearing cup or socket,
a saw-guide-carrying post, having a ball end bearing in said cup or socket, and
means for securing said post in different positions of rotary and angular adjust-
ments.
3. In a miter box or machine, the combination with a supporting-base having
a hemispherical socket, of a saw-guide-carrying post having a ball end bearing in
said socket, means for guiding and holding the upper end portion of said post,
a radial rod connected to said post, and means for securing said rod in different
positions, substantially as specified.
4. In a miter box or machine, the base having on its surface two equal squares
having a common side, and whose sides are marked by scales, a subdivided are
inscribed in said squares, with an equal segment in each, and a hemispherical
socket at one extremity of the said common side at the center of said are, of the
saw-guide-carrying post having a ball end fitted to said socket, guides for the
upper end of said post, a radial arm attached to the lower end of said post, and
a slide-block slidably engaging the free end of said base and adjustably engaged
by said radial arm, substantially as specified.
5. In a miter box or machine, the base having the hemispherical socket, the
work-support, the back-stops, and the arched guides, of the saw-guide-carrying
post having a ball end fitted to said socket, and engaging the said guides, and
means for securing said post in different angular and rotary adjustments, sub-
stantially as specified.
6. In a miter box or machine, the combination of a base or support, having the
hemispherical socket, the work-support, the back strip, and the arched guide, of
the saw-guide-carrying post having the ball end fitting said socket, and engaging
said guides at its upper portion, means for securing said post in different angular
positions in said guides, a radial arm connected to the lower portion of said post,
and a slide on the opposite edge portion of the base adjustably engaged by said
rod.
7. The combination with a base having on its surface two equal squares having
a common side, and whose sides are marked by scales, and also an are inscribed
in said squares, with a segment lying in each, a saw-guide-carrying post cen-
tered at one extremity of said common side and at the center of the said arc,
means for securing said post in different positions of rotary and angular adjust-
ments, and an indicating wire or cord connected to the said post, substantially
as specified.
8. The combination with the base having its upper surface divided into two
squares having a common side and whose sides are marked by scales of a post or
standard centered at one extremity of said common side, and capable of rotary
and angular movement, and a saw-guide carried by said post or standard, said
base also having inscribed therein an arc of one hundred and eighty degrees
whose center is the center of movement of said post, and whose radius is the
length of the common side, substantially as specified.
9. In a machine of the character described, a base having its surface divided
into two equal squares having a common side, and whose sides are marked by
scales, said base also having inscribed therein a subdivided arc of one hundred and
eighty degrees one quadrant of which lies in each of the squares and whose center
is a point marking one extremity of the common side of the squares, and whose
radius is equal to the length of such side, in combination with a saw-guide
movable over said base, substantially as specified.

page_text: 10. In a machine of the character described, a base having its surface divided
into two equal squares having a common side, and whose sides are marked by
scales, said base also having inscribed therein a sub-divided arc of one hundred
and eighty degrees one quadrant of which lies in each of the squares and whose
center is a point marking one extremity of the common side of the squares, and
whose radius is equal to the length of such side, togother with a saw-guide-
carrying post centered at the center of the said arc and rotatably and angularly
adjustable upon said center, and an arcuate back portion secured to said, base and
forming a guide for said post, the arc of said back portion having the same center
and radius as the arc inscribed on the base, substantially as specified.
Dated this 30th day of September 1899
Witness:-
ROBERT WATSON,
DAVID L. MCDONALD,
Scranton, Pa.,
PATRICK FRANCIES MCDONALD.
Boult, Wade, & Kilburn,
Agents for the Applicant.