Dovetail joinery is a woodworking technique used to connect two pieces of wood together. Today, it is most commonly used to construct drawers. The end of one piece of wood has a line of ‘pins’, trapezoidal in shape, that fit
into the end of another piece of wood having a corresponding line of ‘tails’. This woodworking joint is especially strong and resistant to being pulled apart. The history of this wood joining craft dates back to both ancient Egypt and China.
Furniture found in tombs from both countries was built using dovetail joints.
In today’s furniture manufacturing, two types of dovetail joints (or simply dovetails) are used. The first type is known as English dovetails. As described above, the ‘pins’ of one side of the drawer fit into the opposite corresponding ‘tail’ of the adjoining side. This joint is quite strong, especially when the dovetails are glued together. It is difficult to pull apart two pieces of wood joined by dovetails. Think of it almost as a locking joint. The second most common type of joint is the French dovetail. In manufacturing a drawer box, this technique requires each ‘side’ of the drawer to have one ‘pin’ that runs along the ends or widths of the board; that which will determine the ‘depth’ of the drawer itself. The back side of the drawer box and the drawer front contain the ‘tail’. In this dovetail, the ‘tail’ will be a long groove routed at each end of the board into which the drawer side ‘pins’ will slide. This is also a very strong joint and more so when glued together.
There are a couple of points to remember when looking at drawer box construction. First, by the nature of its design, English dovetail joinery is more expensive to manufacture, even with modern automated equipment. The second point, and perhaps the most important one, is that drawers made using English dovetails have more capacity than a drawer of exactly the same size constructed with French dovetails. English dovetails are assembled at the corners and therefore the drawer box contains the full space available for storage as determined by the dimensions of the sides and bottom of the box. A drawer manufactured with French dovetails by its design will not have the same capacity since the dovetails must be constructed in from the edges or corners, reducing the amount of storage space available in the drawer. In some cases, a drawer with English dovetails can have as much as 28% more capacity than drawers made with French dovetails. There are some manufacturers constructing drawers with English dovetails in the back of the drawer box and French dovetails for the drawer face. This does save some cost while allowing additional storage capacity.