Ding! We have a winner.

wrote in message
...

If I understand correctly this groove is "tapered" from to to bottom.
If so, you could make an angled block or ramp for a router to ride on.
If necessary for your application you could make a base for the router
with a matching slope, that would ride on the ramp attached to the
work piece. This would keep the router perpendicular to the workpiece,
so that the sidewall at the end of the groove was perpendicular to the
face of the workpiece also.


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Larry Wasserman Baltimore, Maryland