One of the most important methods employed by the joiner is that
termed dovetailing, which is of three kinds, namely, common, lap, and
miter. Common dovetailing (see Fig. 97) shows the form of the pins or
projecting parts, as well as the excavations made to receive them. Lap
dovetailing is similar to this, but in that system the ends of the
dovetails of the side A, Fig. 98, are shortened, and the recesses which
are to receive them in B are not cut through when joined together; only
the ledge is visible on the return side.
[Illustration: FIG. 97.]
[Illustration: FIG. 98.]
[Illustration: FIG. 99.]
[Illustration: FIG. 100.]
Miter dovetailing (sometimes also called secret dovetailing) conceals
the dovetails, and shows only the miter at the edges. The manner in
which this joint is made will be understood from Fig. 99, in which the
two parts A and B are given, each part being lettered to correspond
with the position it is to occupy when the sides are joined. Concealed
dovetailing is particularly useful where the faces of the boards are
intended to form a salient angle; that is, one which is on the outside
of any piece of work; but when the faces form a re-entrant angle,
that is, a joint to be seen from the inside, common dovetailing will
answer best; for, first, it is stronger, because the dovetails pass
entirely instead of only partly through; secondly, it is cheaper, for
the dovetails which go through the whole wood take up much less time
in working than where a miter has to be left; and further, if well
executed, the dovetails are, by the very nature of the work, concealed
internally.
Fig. 100 shows a variation of the common dovetail, used in attaching
the fronts of drawers to the sides, and for similar purposes.
[Illustration: FIG. 101.]
In Fig. 101 is given the working drawing of the common dovetail, and
Fig. 102, A-B shows the details of each piece.
The stock can be prepared in one piece (having it long enough so that
if a poor joining is made, the dovetails can be cut off and new ones
cut on this piece). After planing, cut in two, square one end of each
piece (the ends to be joined). To lay out the work, it is advisable to
lay out the piece with the pins or tenons first. From the squared end
measure in the thickness of the side; then mark on both sides, using
the knife to draw the lines.
[Illustration: FIG. 102.]
On the face side (which is the side that would be toward the inside of
a box) lay off the lines shown for the pins in the detail marked A,
Fig. 102. These lines can be drawn from the working edge with a gauge,
or, if the ends are perfectly square, the square can be used (the lines
being parallel with the edge). From these lines will be drawn the
oblique lines across the end with the bevel set at a taper of 1 inch
to 4 inches. The bevel can be set by the steel framing square, by the
methods already given.
After drawing the lines saw down the required depth on the outside of
the line, and remove the pieces between the pins or tenons by first
boring a hole through the piece to be removed, then cutting from both
sides with the chisel.
[Illustration: FIG. 103.]
[Illustration: FIG. 104.]
(The boring is done with the brace, Fig. 103, and the bit, Fig. 104.
Bits are of different forms; Fig. 105 shows a number of different
styles).
It will be necessary only to draw the lines across the end of the piece
marked B, Fig. 102, as the marking of this piece for the recesses will
be made by holding in position the piece already cut, and scribing or
marking the pins or tenons, then squaring the lines across the end.
Great care must be taken in sawing the mortises if a perfect fit is
desired. This can be done only by sawing on the inside of the line,
cutting the lines in two. The pieces should go together by light
driving, and should be perfectly square on the inside. If the joint is
satisfactory take apart and glue together. After the glue is dry the
joint can be smoothed and the ends of the pieces cut off and squared to
the proper dimensions given in Fig. 101.
[Illustration: FIG. 105.]