Years ago when I first learned to cut dovetails, my first joints weren’t things of beauty. Sometimes there were more shims than pins. Over time, my work got better and faster. But despite the improvement in my skills, I still had trouble cutting tails or pins consistently, especially if I got out of practice.
This jig allows you to make great dovetails on your first day. The idea came to me when I was building a Shaker stepstool using hand-cut dovetails. I made a jig that fit over the end of a board to guide my saw through the cut and provide a perfect tail. The jig didn’t cut pins and only worked on 3/4″-thick boards. I guess I wasn’t thinking big that day.
A few weeks later it came to me: Why not build a jig that cuts both tails and pins and is adjustable to a variety of thicknesses? So I made this jig. From the first joint I cut using it, I got airtight joints. It was very cool.
This jig uses a 9-degree cutting angle. Woodworking books say that 9 degrees is intended more for soft woods than hardwoods (which use a 7-degree angle) but I thought it a good compromise. You can build this jig entirely by hand, but I cheated and used a table saw for a couple of the precise angle cuts. Let your conscience be your guide.
One of this jig’s peculiarities is that you’ll sometimes have to cut right on the pencil line. As designed, this jig works best with Japanese-style Ryoba saws on material from 3/8″ to 3/4″ thick. Use the saw’s ripping teeth when making your cuts. You could modify this jig to accommodate Western saws, but you’d have to take a lot of the set out of the teeth so you didn’t tear up the faces of the jig. The set of a saw’s teeth basically allow you to “steer” a blade through a cut. This jig does all the steering. You just have to press the gas. PW
Jim Stuard is a former associate editor for Popular Woodworking.