Using stub tenon and groove joinery to build doors is a mainstay technique in my shop. A centered groove cut in all the frame parts is sized to hold a plywood panel. A stub tenon on each end of the rails also fits in the groove. And since the panel is plywood, it can be glued into the frame where it contributes to the overall strength of the door. However, cutting the joints is only half the battle. Just as important is the assembly process. It can make or break how the door works in a project.
The two photos at the top of the page show how I apply glue. A brush allows you to spread a thin even, layer on the cheeks of the stub tenons. For the grooves, simply run a thin bead along the edge straight from the glue bottle — there’s no need to spread it around. The key is to use the right amount of glue. Cleaning up squeeze out in a frame and panel is tedious work.
To end up with a square and fl at fi nal assembly, I follow a specific routine. The assembly process starts with turning a stile on edge. Then insert a rail into the groove. Make sure to keep the rail fl ush with the end of the stile. Next, I slip the panel into place.
Now, fit the other rail at the end of the panel. Finally, add the remaining stile over the panel and stub tenons.
I set the door flat on a pair of spacers, and apply the clamps across the ends. Just snug the clamps up for now. It’s your chance to check final alignment of the rails with the ends of stiles. At this point, you can use a square to check the frame. It’s a good idea to measure across the middle of the door, too. The panel may cause the stiles to bow out slightly. So you may need to add a clamp to draw the stiles straight. At last, tighten down the clamps. In a few hours, you can take the clamps off and be confident that the door is ready to go.
