By David J. Marks
Dovetails are one of the oldest and strongest joints known to woodworkers. They are also one of the most aesthetically pleasing. For thousands of years they have been cut by hand, holding pieces of furniture together even after the hide glue that was used failed. With the invention of the electric router in modern times came a myriad of accessories to complement this tool, helping it to earn the well deserved title of one of the most versatile tools in the shop.
Dovetail templates are one of the most widely used of all router accessories. These templates enable woodworkers to consistently produce furniture with strong, tight fitting joinery piece after piece. There are a variety of templates on the market. Most of them have fixed spacing which means that the layout pattern is predetermined and symmetrical. These are the fastest and easiest to use.
The type I favor has variable spacing. I like this type because they allow the craftsperson more design options as opposed to locking you in to a fixed spacing. They also look more like hand cut dovetails. The newer models will cut half blind dovetails as well as through dovetails. I love the look of through dovetails on casework and I find the end grain provides a pleasing contrast to the long grain of the pins. For drawer construction, if you are working on a traditional or formal piece, then you won’t want the end grain to show and this is where half blind dovetails would be a good choice.
Half blind dovetails can be very time consuming to cut by hand so if you have a dresser to build or another situation that requires a lot of these joints, than using a dovetail jig is the way to go.
Both through and half blind dovetails are very strong, due to the fact that they interlock mechanically and they have a lot of long grain to long grain glue surface. The jigs require a dovetail bit and a straight bit. Mounting a template guide on the base of your router permits you to guide the two different bits through the templates creating tight fitting dovetails. The jigs have adjustments to tighten or loosen the fit. I always recommend making test cuts and practice pieces. This rule also applies with router templates. Dovetails can easily confuse people, so making sample pieces that are labeled will enable you to stay on track and make the process much more enjoyable.