I was asked to discuss this joint for KD (knock down)
construction. The pictures are of a large table I made about 12 years
This is an easy joint and it looks hand crafted...
The easy way
is to make a rectangular template the size of the mortise and using
a top bearing bit rout down as far as the bit will go... remove the
template and the mortise becomes the template as you continue
through the piece... back it with scrap when you come through to
The tenon is cut by hand, bandsaw, or tablesaw to
the exact size of the mortise. Since the router bit left a square
with inside rounded corners, use a matching roundover on the tenon
and you don't have to square it. Of course you can if that's
the look you want... which is nice also.
So a 1/2" straight bit will match
with a 1/4" radius roundover... no calculus needed... The wedge in
the pics is made from ebony and it is cut on the bandsaw and shaped
by hand or machine and hand sanding... carving... chewing with your
teeth - skip the last one!
It is important to drill the hole for the wedge a little inside the
depth of the second member... in this case a leg... That way when you
tap in the edge it tightens the gap between the stretcher and leg...