In planning stairs of this description several things have to be
considered. First take off the height and going on a rod. Then decide
how many steps there are to be. Draw a plan and elevation, as shown
at Figs. 1 and 2. Set off the width of the stairs and draw the two
newels. Now draw the line of travel 15 inches from the centre of rail.
Take the centre of newels for centre, and strike the quarter of circle
top and bottom in continuation of this line, which divide into as
many divisions as there are to be steps. In drawing the winders keep
the narrow ends as wide as possible, and for this purpose they can be
brought past the newels into the strings; as we can have no sympathy
with the system that crowds all the narrow ends of winders into the
newels, by that means making the stairs unnecessarily dangerous. The
dotted lines show the trimmers and joist; care must be taken to have
sufficient headroom. It will be noticed that the wall string is jointed
at both ends, so as to get sufficient width. When these strings are set
out like this to a scale, it is seen at once what there is to joint on.
Fig. 3 shows the short string at the bottom, and Fig. 4 that at the
top. These short strings must be made to ease into the long wall string
at the same height, also to ease into the skirting. To fix these stairs
proceed as follows: set the steps 1, 2 and 3 at the bottom, and 12, 13
and 14 at the top, out full size on a board, with the wall strings and
newels. Tongue and groove the strings together in the corners, having
the tongue on the long string at the bottom. Mark the treads off the
board to cut and not try to fit on the job. If the rods have been set
out correct in the first place, and as correct can be worked to, they
can be cut in the shop for the bottom winders, but for the top ones
the lines should be taken off the board out to them, and cut when
fixed. Put the flight together, including step No. 12 at the top and 3
at the bottom, then fix on the bottom newel, after which step No. 2 can
be fixed in position. Then put the short string in its place, also step
No. 1. Now let the stairs go down into their place and do all necessary
blocking and screwing. It will be understood that everything has been
fitted before this, also that these bottom winders are glued up. Next
put on the long newel and glue and pin it; slip the short string at top
into its place, then fix in the risers 13, 14 and 15, and treads 13 and
14 and the nosing at top. Glue, screw and block these after they are
in. Before cutting the treads and risers at the top, try with a rod to
see if the lines on them taken off the board are correct, and if there
is any difference allow for it when cutting them in.
Fig. 5 shows the plan and Fig. 7 the elevation of the newel for the
bottom, with part of winders to 1½ inch scale. In setting out the
newels mark the position of risers on to them, thus, make 1, 2, Fig. 7,
equal to 1, 2, Fig. 5, and set up the height of a rise, and square out
a line and make 2, 3 equal 2, 3, Fig. 5; this riser, it will be seen,
comes on the edge; again set up a rise, as shown by 3, 3. From 3 square
out a line and make 3, 4 equal 3, 4, Fig. 5, and set up the height of
a rise. The same process would be repeated as long as there were any
risers striking the newel on plan. Of course the newel would be set out
full size on the board that the winders were set out on.
Fig. 6 shows the plan of newel, and Fig. 8 the elevation of a part of
it. Repeat the process described at Figs. 5 and 7.
[Illustration: PLATE 7.]