Wood Joints - Mitered Butt Joint

This is probably the most common joint you'll see in wood plans. Mitered butt joints are everywhere—from the picture frame on your desk to the baseboard molding along the floor. When a full butt joint is just a little too rough for your project, a mitered butt joint can add just the right amount of finesse to an otherwise awkward-looking joint.

Problem is that mitered butt joints are notoriously difficult to clamp and glue up without going out of square. Not to mention that by itself, a mitered butt joint is fairly weak, even if you’re able to get a tight glue up. For most projects, you’ll want to consider some type of reinforcement for this type of joinery. For example, a spline may be all you need to add just enough support to keep things together.

As the name implies, this is a simple miter joint with a wooden spline glued in between the joining boards. Cutting a splined miter calls for some work on the table saw, but you won’t need any fancy blades (like dado blades) to make the cut. The width of your saw blade will make a perfect slot for the spline. See how to cut a splined miter joint.