For most mortises, the only "passes" you want to make would be on depth of
cut, not width.
Mortise widths are generally based on two things, the width of the material
into which the mortise is being, and/or the width of the chisel with which
it's being cut .
You would do better, IME, to get the exact size router bit for the planned
tenon, ie, 1/4", 3/8", 1/2" ... you can always plane or otherwise adjust the
tenon if need be to get that just right fit.
Last update: 1/02/04
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