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Now that I have my CNC machine up and running, my first project is to make some routing templates for my O'Brien neck angle jig that will work for Benedetto-style dovetail joints. I've used a different style dovetail on my archtops before, but I thought I would try the Benedetto style now.

I confess his approach has me a little confused, and I'm hoping someone can help me make sense of it.

Benedetto uses a dovetail, but it does not have a v-shaped taper. Instead, he makes something that is an interesting cross between a mortise-and-tenon and a dovetail joint.

But here's the confusing part: On the neck dovetail, the narrow part of the mortise is 15/16". On the body, the top of the mortise is 1" at the narrow part, and then it tapers down to 15/16" at the bottom of the mortise. So, the top essentially has 1/16" of wiggle room. The way he describes it in the text of the book and his video suggest that the bottom of the mortise is actually narrower than the tenon, such that it squishes in, but the dimensions in the book suggest the opposite.

Does anyone here use his joint? Do you make it with a 1/16 gap at the top, as the dimensions in his book suggest? Or do you taper it so that the dovetail has to compress 1/16" at the bottom? Or do you skip the taper and just make it even all the way down?