I received this via email from FWW and it got my curiosity. According to the free plan the cabinet shelves are 3/4" t and the tapered dovetail socket is 5/16" deep (3/8" w at the front and 9/16" w at the back). Interesting but seems too complex for a simple cabinet. Why not use plain old dados cut on the TS to support the shelves? Of course that simple method isn't the stuff that FWW would publish.
Ep 3a: Hand-cut Tapered Dovetails - Sockets - FineWoodworking
In this episode, Chris begins creating the tapered sliding dovetails by sawing out the sockets, and cleaning them up with a router plane
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