In Part 1, I talked about the joint itself, and discussed some terminology and tools that are used when working with dovetail joints. This time, I’ll walk you through prep work and cutting on the tail side of the joint. Although this process works well for me, it is certainly not the only way to do it. I strongly encourage you to try a variety of techniques to understand what workflow is best for you.
A tight- and well-fitting dovetail joint is heavily dependent on the prep work. Long before the dovetail saw or chisels come out, you have already determined the fate of your joint. Preparation of the boards to be joined is just as critical as the joint itself. Oftentimes, we rush our prep work because “it’s only a practice joint”, but this is a critical step in the process.
Whether you use hand tools or power tools, the goal in your preparation is to ensure that the two boards to be joined are straight, flat, and have one square end. Clearly mark the face side of each piece as well as one adjacent long grain side. When choosing the face side and the orientation of the boards be sure to consider the grain patterns and colors of each piece, and how they will look together when fully assembled.
Mark Your Boards
Once your boards are prepped, you can begin the layout process. I mark my base lines first in pencil and follow with a marking knife later. Mark your baseline at just over the thickness of the adjoining board. This will leave the tails and pins slightly proud; after we’re done we’ll trim them flush. Mark the base line on one face grain side and then transfer it around to all four sides with a good square.
I choose a tail first process so I will set my pin board aside for now. Layout where you like the tails using dividers, math, or just your eyeball. Many craftsmen believe that thinner pins (i.e. – less space between the tails) is more aesthetically pleasing, but there are no hard and fast rules. I typically go with a 1:6 or 1:8 ratio for my tails. I use a marking knife to layout the tails on the face side of the board first. Then I transfer it across the end grain with a square and finally down to the other baseline with either a dovetail marker or a bevel gauge. CLEARLY mark all the waste, I do so by coloring it in with pencil on all faces.
Making the Cuts
First, use a dovetail saw cut the sides of the tails down to the base line. I like to place my thumbnail in the knife line on the end grain and rest the saw up against it to guide the start of the cut. Pay attention to the baseline on both sides of the board as you get close. Repeat this process until you have cut on both sides of each tail. I’m right handed, so I prefer to always cut on the right side of my marked line. I’ll cut the right side of each tail first. Then I’ll flip the piece 180 degrees in my vice, then cut the “new” right side of each tail again. Use a coping saw or similar to cut away the waste between any two tails. The waste at the edges of the board can be removed with the dovetail saw.
Finally, use chisels pare all the cut edges back to the knife lines. Depending on your proficiency level with a saw this may require a little or a lot of effort. It is extremely helpful to practice your sawing technique such that very little paring is required. You may have seen people on social media doing a 30 day dovetail challenge; that’s a great way to build your skills!
In Part 3 of the series, we’ll cut the mating pin board for this joint, and we’ll actually fit the joint together.