Picture Frame Spline Jig: 3D Print a Saw Guide for Strong, Decorative Frame Corners

A wooden picture frame corner resting in a matte red 3D printed spline jig on a workbench

Introduction A mitered picture frame corner is beautiful and, on its own, not very strong. The joint is end grain glued to end grain, the weakest bond woodworking offers, and it is why old frames so often gap at the corners or come apart in your hands. The classic fix is the spline: a thin … Read more