Types of Wood Joints in Carpentry
When two pieces of wood are to be jointed together, as in cakeboards,
buckets and pails, or furniture, many methods are used, depending
upon the material, the strength required, and the character of the
work in hand. In former times all joints were made by hand, but
now every kind can be made more accurately by machinery.
The three types of jointing are:
Straight-angle jointing, Edge-to-edge jointing, End-to-end jointing.;
and each type can be effected in various ways.
The simplest method of joining two pieces of wood at right angles
is by nailing or screwing. This serves for rough work, but is clumsy
and not very strong.
A better way is by what is called the half-and-half joint, in which
one-half the material at the end of each piece to be joined is cut
away. (See Figure 5.) If carefully done this makes a serviceable
and neat joint.

Figure 5. Different Kinds of Joints
A - Half-and-Half Joint. B and C - Tenon or Tongue-and-Groove Joint.
D - Dovetail Joint.
The mortice-and-tenon or tongue-and-groove joint is excellent where
neatness and strength are required. It is used in straight-angle
and edge-to-edge jointing also. This may be seen by looking at the
end of a bread board where the small end pieces are joined to the
body of the board. The protruding parts of one piece fit exactly
into corresponding notches in the piece to which it is joined. (See
Figure 5.)
Another very strong joint is known as the dovetail joint. In this
type the projecting pieces of wood, wider at the tips than at the
base, fit into corresponding sockets. This is seen in bread and
cake boards, but is not used so often as the mortice and tenon joint.
When an unusually strong, heavy joint is required, wooden pegs,
called dowels, are driven tightly into auger or gimlet holes made
in the joints. These dowels are of strong, hard woods, such as beech,
maple, etc. Over 12,000,000 feet of lumber are used annually in
dowel-making.
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