Four Reasons for Tails-first Dovetails
When it comes to dovetailing, I’ve never really had a dog in the fight between dovetailers who cut the pins first and those who cut the tails first. I was first taught to cut my tails first, though I’m also comfortable cutting the pins first (I spent a whole year cutting pins first so I understand its advantages).
But as I get older, I guess I’m getting more set in my ways and am officially entrenched with the tails-first crowd. Why? Well I guess it’s because of the tools I use and processes I have chosen through the years that make my choice inevitable.
Reason 1: Gang cutting. I like cutting two sets of tails simultaneously for drawers. This is impossible to do (well) if you cut pins-first.
Reason 2: I own a narrow-bladed knife. One of the big advantages of cutting pins-first is that you have a lot of room to navigate when you transfer your marks to the tail board. I have a very narrow-bladed knife, so sneaking it between the tails is no hassle for me. If I didn’t have this tool, I’d probably be a pins-first person.
Reason 3: I rabbet my boards before cutting the tails. Years ago, Glen D. Huey showed me a trick where you rabbet the inside face of your tails to make transferring the marks to the pin board easier. The shallow rabbet (about 1/8″) gives you enormous precision in aligning your pieces. Glen is a pins-first guy, and the system works with pins-first dovetailing. But I think it really shines with tails-first because you can clamp your pin board in a vise and really apply pressure with the tail board.
Reason 4: Gravitational forces. This one is a subtle argument, and I don’t expect it to sway many people, but it is a strong one for me. I think it’s easier to cut a true vertical line than it is to cut a true line at an angle. This is because of the way gravity tugs at the heavy back of the saw. This little detail makes cutting tails-first easier for me. Here’s how:
When you cut any dovetail, the first half of the joint is the pattern for the second. So your first part doesn’t have to be precise when it comes to its angles. It just needs to be clean and neat. If you cut your tails first, that means your first cuts are angled. If you don’t have to be precise with these cuts, then you have one less thing to worry about with this part of the joint. All you really need to worry about is being straight. The actual angle is incidental. Heck I use a pencil alone to mark out my tails.
When it comes to the second part of the joint, it must be an exact complement of the first. Accuracy counts a great deal. When you cut tails-first, that means your second cut is pins. And pins are straight up and down. And straight up and down is easier to do perfectly. Well, straight is easier is for me at least.
If you reverse the process and cut the pins-first, the second part is making the angled tails. And I think those lines are harder to track because gravity isn’t on your side.
Of course, if you do this stuff every day, all this becomes moot. You just do it the way you do it. And you ignore the gravitational prattling of a magazine editor.