A joint is chosen for the load it has to carry, not for how it looks. Reading a joint by the direction it resists pulling, racking, or shearing makes the choice between them straightforward. The four below cover most early projects, from the simplest to the most demanding to cut.
The butt joint
Two pieces meet end to face or end to end with no interlock. It is the quickest joint and the weakest, because it relies entirely on the fastener or glue holding the joint and on end grain, which bonds poorly. Reinforced with screws, dowels, or a pocket screw, a butt joint is fine for a back panel or a quick frame, but it should not carry weight on its own.
The rabbet and the dado
A rabbet is a step cut along the edge of a board; a dado is a square channel cut across the grain. Both add a mechanical shoulder that locates the mating piece and resists racking, which a plain butt joint cannot do. Dados are common in shelving: the shelf sits in a channel cut into the side, so the joint carries the load instead of the fastener alone.
A useful rule of thumb: if a joint has to stop a part from sliding or twisting, look for one that adds a shoulder or a channel rather than relying on glue at an end-grain surface.
The mortise and tenon
A tenon — a projecting tongue — fits into a mortise, a matching cavity. This is the backbone of frame-and-panel work, doors, and tables, because the long-grain surfaces inside the joint glue strongly and the shoulders resist racking. It takes accurate layout and patient paring, which is why it rewards the marking and chisel work covered in the tools article.
The dovetail
Angled pins and tails interlock so the joint mechanically resists being pulled apart in one direction — the reason it is traditional for drawer fronts, where the front is pulled every time the drawer opens. It is the most demanding of these joints to cut by hand and is usually the last one a beginner takes on.
Choosing between them
| Joint | Resists | Typical use |
|---|---|---|
| Butt | Little on its own | Back panels, light frames |
| Rabbet / dado | Racking, sliding | Shelves, case backs, drawer bottoms |
| Mortise and tenon | Racking, pulling apart | Frames, doors, tables |
| Dovetail | Pulling apart one way | Drawer fronts, boxes |
A note on wood movement
Solid wood expands and contracts across its width as humidity changes, and in Canada the swing between a dry heated winter and a humid summer can be significant. Joints and assemblies are designed to allow this movement — for example, a solid panel is held in a groove so it can move without splitting. Ignoring movement is a common reason early projects crack or rack out of square over a season.