Spline Joints

A spline is the traditional name given to a long thin strip of wood. The spline joint works by holding the mitred corners of a frame together with one or more splines. These are glued into slots cut through both sides of the corner.

In this article I’ll show you how to make simple lightweight spline joints using hand tools. Simple spline joints can be used for small-scale work but they do not have much strength, so I’ll also look at making a sturdy alternative called a keyed spline joint, made with basic power tools – a mitre saw and a small router fitted with a dovetail cutter.

Preparation

First, all the wood needs to be planed straight and square before marking out or cutting spline joints. When you plane narrow edges,