Fig. 1 shows the plan, and Fig. 2 the elevation of a part of an open
or cut string. It will be seen the risers are cut like a bare face
tenon 5/16 inch thick, the same thickness as the ornamental brackets,
and shouldered to fit against the inside of the string. These brackets
are glued and bradded to the outside face of the string, and mitred
to the ends of the risers. That part of the string where the shoulder
of the risers fits against, should be gauged to an exact thickness.
The brackets fit close up under the ends of the treads, which project
the thickness of the brackets past the strings, and mitred on the
front edge to receive the return nosing and scotia, which is mitred
and returned into the string, as shown at E, Fig. 1. The best method
to adopt is as follows:--Get the risers shouldered and mitred, then
plough the treads for the scotia; now cut off the ends of the treads
as far as the mitre, which mark and cut in a little way, finishing the
cut after the nosing has been worked and the stairs are together. Cut
in the dovetails for the balusters, but not chop them out before the
stairs are fixed. Now glue in the scotia, and, when dry, put the steps
together, the same as was explained in Plate III. Then get the length
of steps from the width rod, and cut them off. Gauge the risers to a
width with a gauge as seen at Fig. 4. Fit the steps in the wall string,
and cut out for nosing and scotia. To put them together, lay the wall
string on the floor, having it straight and solid; put the steps into
it, and lay the outer string on, and, with struts from the ceiling or
any convenient place, force the cut string on to the shoulders of the
risers, and the steps into the housing of the wall string. See that
the stairs are square before doing all necessary wedging, blocking,
screwing, &c. Then remove the struts and put on the brackets and return
nosing, glueing and bradding the former, while the latter should only
have two brads into the steps, so that they can be easily removed to
fix the balusters when the handrail is fixed, after which they can be
permanently nailed. The iron balusters are screwed to a block fixed
for the purpose. This block is marked A, Figs. 1 and 3. The riser is
reduced to allow the block to come forward, so as to get the screws
well into it; it is stub-tenoned into the under side of the tread, as
shown by the dotted lines, Fig. 3; it is also screwed into the back of
the next tread below, and well glued and blocked. There will have to
be a special baluster turned, out of pine, for a pattern, and turned
a little longer to allow for shrinkage in the casting, which is about
⅛ inch to each foot. The square parts must be made to draw out of the
sand when cast--that is, they must be a trifle thicker in the middle
on the sides shown at Fig. 3 than they are at the edges, as they are
cast in two halves. They will be drilled and countersunk for the screws
after they are cast.
Fig. 5 shows the side and Fig. 6 the front elevation of a mitre shoot
for shooting the mitres of the ends of risers. The sides are two 9-inch
boards, set up at 45°, and screwed to the bottom, marked D, and to the
back, marked H. Two ledges are screwed on the bottom, marked N. Also a
longer piece on the top, in front, marked C, for the trying plane to
slide on when shooting the mitres. A false bottom is put in, and set
up at 45°, marked B, this is screwed or nailed through the sides, and
kept ½ inch above C, as shown. The triangular piece is put in, and the
bottom side S P is kept the thickness of a bracket above B, and S P
must be the exact size of the thickness of the string where the risers
fit against it. The risers are put in with the shoulders against S R
and shot off. The brackets can be mitred in the same way. This box will
do for any job by having different triangular pieces.
Fig. 7 shows how to get out the continuation of the brackets along the
top landing, and finish against the wall. It often happens that the
brackets require to be reduced in length for unders or diminished
flyers, or increased for a large well, or where the risers are farther
apart than on the straight flights. Figs. 8 and 9 show methods of
reducing or increasing the length of the brackets, and each member
proportionately. It is only necessary to describe one, as the method
for both is the same. Let A be the given, and B the required bracket.
Having drawn the bracket A, set off C E at any angle, the required
length. Join D E, draw any number of lines on the bracket A, square
to C D, draw these lines parallel to D E, and from where they cut C E
square outline, and make them equal corresponding lines on the bracket
A, as 3, 4 and 5 on B will equal 3, 4 and 5 on A. These brackets for
the circular parts may be got out of wood; in that case the grain
should be vertical, as the brackets are fixed. But for painted work the
best are two pieces of linoleum glued together.
Fig. 10 shows how the cut string, which is 12 inches wide, may be got
out of a 9-inch board. Shoot the bottom edge, then gauge a line on its
face to equal S S, Fig. 2. Then with the compasses set off on this
line, the hypothenuse of the pitch board as many times as is required,
as shown by N R S H. Then with the steel square mark each going and
rise, which cut, it will be found the board is not wide enough, but the
pieces cut out of the corners can be glued on to make it out as shown
by A and B.
In some cases, where there are no ornamental brackets, the ends of
treads are cut off flush with the outside face of string, except the
mitre for the return nosing, and the risers are mitred to the string.
[Illustration: PLATE 9.]