Decorative boxes are made to hold everything from jewelry to personal treasures in hope chests. To add beauty to the construction, box makers use decorative joinery to both beautify and strengthen the points where the sides meet. Even the most humble and simple of joints will be strong enough for most applications so joinery decisions are usually more about art than engineering.
Here are some commonly used techniques:
Butt Joint – The ends of the boards are simply butted together and glued. It’s a relatively weak joint and since it exposes the end grain for one of the boards, it’s not particularly attractive. It’s quick and easy but the glue joint is not very strong so butt joints are often reinforced with brads, screws or biscuits.
Mitered Joint – The ends of the boards are cut at a 45 degree angle and glued together. With their clean look, miter joints are aesthetically pleasing. No end grain is exposed so the joints seem to just disappear. They’re easy to produce as long as the angles are perfect.
Splines can be used to add interest and strength to mitered joints. A spline is a thin strip of wood inserted across the grain. They can be hidden inside the joint by slicing vertically along the angled faces or splines can cut across the outside edges of the box. Using a wood that contrasts with the box sides will emphasis the spline and make it stand out.
Finger or Box Joint – As the name implies, a finger joint consists of a series of uniform interlocked ‘fingers.’ Before the invention of cardboard boxes, manufacturers made containers for their products out of very thin wood with box joints because they were strong and could be machined quickly.
Dovetail Joint – A hallmark of craftsmanship, dovetail joints can be cut by hand, machine or a combination of both. They are great for all kinds of boxes; they are both strong and decorative. Like box joints, dovetails consist of a series of interlocking pins cut into the ends of the boards. The difference is the trapezoidal shape that locks the pieces together. The resulting joint is very strong and needs no additional mechanical fasteners. Hand cut dovetails require practice, time and patience to master but offer more flexibility and room for creativity. Machined dovetails can be produced quickly with a jig and router or a dedicated machine. Done well, it can be difficult to tell which method was used.
Another option is to skip the joints altogether and make the box from a single piece of wood. It’s tedious to hollow a block, but it can be done with drill bits and chisels. Or a clever sequence of cuts on a bandsaw will yield a smooth flowing look. Boxes can also be made on the lathe or scroll saw.
Next time you see a box, take time to look at the joinery and see how the choices the woodworker made enhance the beauty of the piece.
