"Chris Friesen" wrote in message
el...

The problem with that approach is that the diameter of the router bit has
to
be dead nuts accurate, which in my experience most of them aren't, or
else
you need to do some fine tweaking on spacing to avoid a joint that is too
loose or too tight. With dovetails you can fine tune the fit with cut
depth, with box joints you don't have that option.

The Leigh jig uses an elliptical bushing and a bit smaller than the
desired finger size. You turn the router base slightly to adjust the fit.

Actually you adjust the bushing slightly and keep the router orientated the
same for a repeatable cut.

I have to wonder however why they changed over to this set upas the D series
system used a tapered bushing. Rotating the router had no adverse effect on
the cut assuming the set up had the bit centered in the bushing.