How to join wood with dowels

In making or repairing furniture, it’s easier to join pieces of wood with short wooden pins, or dowels, rather than with hand-cut joints. In any situations dowels are stronger than nails or screws, and they need not show unless you want them to.

You make dowel joints by drilling corresponding holes in two pieces of wood. Then you insert glue and the dowels and clamp the pieces together until the glue dries. In this manner, boards can be joined edge to edge to form tabletops or countertops, or parts of furniture can be securely fastened together.

Ready-to-use dowels are available in various sizes from woodworking suppliers and hardware stores. Choose a dowel with a diameter equal to one third the thickness of the wood into which it will be installed. The length should be 1/8 inch less than the combined length of its two installation holes, which should be drilled through at least one-third of the thickness of each piece of wood being joined.

If you prefer to make your own dowels, purchase lengths of dowel rod in the required diameter and cut them into suitable segments. Cut a groove along the length of a homemade dowel so that air and excess glue can escape during installation. To make this groove, clamp a handsaw upside down in a vise and rub the dowel on the teeth. Then use a file to bevel the ends of the dowel so that it will enter the holes easily.

Aligning and drilling the holes
A dowel will seat properly only if the two holes are aligned with each other and drilled perpendicular to the surfaces being joined. If you plan to install a number of dowels, a commercial doweling jig is a worthwhile investment. Jig designs vary; for best results get one with guides for different size drill bits.

If you don’t have a jig, align the installation holes by nailing brads at the centers of the hole locations on one piece of wood. Then clip the brad heads, leaving the shanks protruding about 1/6 inch. Align the mating piece, then press down on it so that the brads indent its surface. Remove the brads with pliers. Before drilling the holes, enlarge the brad marks in both pieces of wood with an awl.

The holes must be precisely centered on the marks. Choose a bit the diameter of the dowel. To ensure that the bit enters the wood perpendicular to both the length and width of the surface, it’s best to use a drill guide. If you use a doweling jig you run less risk of error. To make your holes the correct depth, measure the dimension on the bit and mark it with masking tape to show you where to stop drilling.

Another way to align the holes is to use commercial dowel centers of the appropriate diameters. Drill the holes in one piece of wood and insert the dowel centers. Align the mating piece and press down so that the doweling centers mark the surface. Drill holes at the marks and remove the dowel centers from the first piece. installing the dowels Blow wood chips from the holes. Apply glue to one end of the dowel and around the edges of the hole in one of the surfaces to be joined. Insert the dowel into the hole and tap it home with a mallet. Then apply glue to the other end of the dowel, the other hole, and the surfaces of the two pieces. Use clamps to draw the pieces evenly together.

Wipe off the excess glue. Keep the pieces clamped overnight.

If a hole is misaligned, fill the hole with a dowel, saw it flush with the wood, sand it, and start over.