Improvements in Set Squares.
Year: 1893

page_text: Date of Application, 21st Jan., 1893-Accepted, 4th Mar., 1893
COMPLETE SPECIFICATION.
Improvements in Set Squares.
I, FRANK ERNEST WILKINS, of 47 Vine Street, Coventry, in the County of
Warwick, Schoolmaster, do hereby declare the nature of my said invention and
in what manner the same is to be performed to be particularly described and
ascertained in and by the following statement :-
My invention has for its object improvements in set squares by which I provide
a set square which combines the utility of two or more set squares as well as a
protractor or article for setting the angles of polygons.
Hitherto it has been usual with draughtsmen to use say two set squares .e. one
of 60° and one of 45° but by my invention I amalgamate the two thus reducing the
number of articles lying on the board of the draughtsman or student.
In order that my invention may be clearly understood and more easily carried
into practice I have appended hereunto drawings showing more fully the nature of
my improvements.
Figure 1., is an elevation of one side of a 45° set square with a combination of
a 60%
Figure 2., is an elevation of the reverse side of the same set square.
Figure 3., shows a modification in the combination of the 60° and 45° set
squares.
Figure 4., shows a combination of three set squares in one.
Figure 5., shows a further modification of the combination.
Figure 6., also shows a modification by which five angles are provided on the one
set square.
Figure 7., also shows a modification which will be fully described hereafter.
In carrying my invention into effect I form the set square A of vulcanite, horn,
wood, metal or other suitable material the one side a being cut to say an angle
of 45° which is the angle most called for by draughtsmen and others and out of
the centre I cut an aperture B which forms an angle of 60° being the next angle of
importance to that of the 45°. On one side of this set square I mark the lines a²
to form a protractor while on the reverse side I mark lines a³ for marking off the
angles of the various polygons. In Figure 3 the combination is shown reversed
the 60° angle d' being outside and the 45° angle d cut out at the centre d³. In the
case of Figure 4 the outer shape E forms an angle such as 60° while the edge e¹
forms a 45° angle the edges e and ea forming other angles which are useful to such
as architects for the various pitches of roofs &c. In the combination shown by
Figure 5 various augles f¹ƒ³, f³, f, f, and ƒ are obtained which may be
modified to suit various requirements. Figure 6 is a further modification in which
the double set square H and H¹ is formed having the apertures h* and * so that the
edges and form inclines by which lines can be drawn at those angles to
the right angle edges of the set square while h' is cut away to form a protractor.
In Figure 7 G shows a further modification in which four set squares g¹, 9², 9³,
and are combined while the slot g' is provided for obtaining the right angles.
It will readily be seen that many other modifications can be made up without
departing from the nature of my said invention and I may apply the polygonal
protractor to ordinary set squares if I so desire. I am aware that set squares
having more than one angle upon their oblique edge are common to draughts-
men but

page_text: Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1st. The improvements in set squares substantially as and for the purpose herein
set forth and shown upon the accompanying drawing.
2nd. The improvements in set squares in which the centre of the square is cut
away to form a set square or squares of different angles substantially as herein set
forth and shown upon the accompanying drawing.
3rd. In the improvements in set squares the combination of a protractor or
protractors with a set square substantially as herein set forth and shown.
Dated this 20th day of January 1893
.7.
GEORGE BARKER,
77, Colmore Row, Birmingham, Agent.
.7.
GEORGE BARKER,
77, Colmore Row, Birmingham, Agent.