In the previous show we started talking about the various methods of joinery that are available to us as woodworkers. As I mentioned in episode 17 choosing the right method of assembling a project often has more to do with a woodworkers personal preference than just about anything else. We need to remember that chances are there’s always more than one way to join components in a project, the question is just a matter of how much strength is needed at the joint and does the joint stay consistant with or maybe even add too the look that you wanted for your project. It’s important to remember that each joint has some sort of limitation, whether the limitation has to do with the amount of stress that can be beared down on it or the amount of time and experience it takes to create it successfully. For this second half of the joinery talk, we’re going to be introduced to the dado joint, the finger joint, the lap joint, mortise and tenon joints and the dovetail joint.
When done correctly the dado joint provides not only a great deal of strength to a project but also acts as a guide for keeping pieces together during assembly. The dado joint is made up of two components, a groove cut in the face of the first piece and the second is the mating piece that sits in that groove. The basic version of the dado is the “through dado”. A through dado is nothing more than a dado in which the groove is cut from the back edge to the front edge and the mating piece just sits in the dado. The next type of dado is the stopped dado. The stopped dado can give a project more of a finished look vs. the somewhat more utilitarian look of the through dado. The third type of dado is the blind dado. The blind dado is made up of a groove that is completely cut inside the face of the piece.
Finger joints are most commonly associated with boxes or even drawers. The many interlocking fingers of the joint provide a great deal of extra gluing surface which contributes to the strength of the joint. As the name implies this joint is made up of numerous interlocking fingers. Most people use the table saw along with a jig to make them. There are numerous homemade jigs out there so it’s really easy to find one on the internet.
The next joint is the family of lap joints. Lap joints are commonly found in frame construction either at the corners or in the middle of a piece where two or more components cross each other. This family of joints is very simple to construct. The first type is the shiplap joint. The next lap joint is the half lap. The strength of the joint is found in the shoulders that are cut when making it, the shoulders are vital in decreasing any racking that may occur when stress is applied to the joint.
Mortise and tenon joints have been around forever, very common in all sorts of traditional furniture building and even timber framing. They are a very strong joint for joining components at right angles to each other and are especially great for where a joint needs to capable of sustaining a great deal of stress. The joint is made up of two main components, the mortise and the tenon. The mortise is a deep groove and the tenon is a tongue that fits inside that groove.
The last family of joints is the dovetails. A very traditional joint, often associated as a trademark of craftsmanship. There are two parts to the joint the tails and the pins, often seen in box construction, small boxes and large chests the traditional dovetail is the through dovetail. The through dovetail is characterized by the interlocking joint of wedge like cuts seen on the face of one board and the endgrain of its mating piece. For drawer construction and some box construction the halfblind dovetail is very popular.
So, that was a lot of information thrown at you, huh? Well as I’m working on this episode I realize that I think we need to breakdown a few of this joints a little bit more, especially those that are basic and vital to construction. So I think that we’re going to devote a few shows to covering a specific joint so that we can understand how to create it.
Thank you again for all the emails and keep them coming. Straight grains and sharp blades, Matt.