Video: What is a Mortise and Tenon Joint
A mortise and tenon is one of the most well-known and useful means to join wood together. Primarily used in solid wood woodworking to join end grain to edge grain. A mortise and tenon joint is, at its most basic, a peg fit into a hole. We show you the parts of a mortise and tenon joint and how it should fit together.
Skill Builder Video
What is a Mortise and Tenon Joint - Video Transcript
Speaker 1: Let's take a closer look at a mortise and tenon joint. The tenon is this rectangular portion on the end of the workpiece. It typically has four shoulders that wrap all the way around it, they're these horizontal portions. The vertical portion of the tenon is called a "cheek". Now, tenons fit into mortises on the mating workpiece. A mortise is nothing more than a four-sided hole that's sized to fit the tenon. Now, on a typical mortise and tenon joint, the thickness of the tenon is about one third the thickness of its workpiece. That makes the tenon reasonably strong, but it also leaves enough material around thee mortise, which is called the mortise "walls" to make the mortise reasonably strong too. Tenons can be thicker than one third with narrower shoulders so long as the mortise workpiece is thicker, so that its strength won't be compromised. Now, here's a few more things to know about tenon shoulders. They serve three purposes. One, shoulders prevent the tenon from ceding completely in the bottom of the mortise. That leaves some clear space at the bottom of the mortise for glue to migrate. Shoulders also add some lateral stability to the joint and they completely hide the mortise when the joint is assembled. That's why when you're making mortise and tenon joints, you want the shoulders to line up all the way around the tenon, and you want the cheeks of the tenon to fit snugly against the walls of the mortise. A well-made mortise and tenon joint should fit together like a piston and a cylinder.