Steve in Thunder Bay wrote:

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Perhaps you could kindly explain one thing that puzzles me about the=A0
two particular routers here. Both have a very large notch opening in=A0
the front that emulates the open arrangement of some router designs
so=A0 that you can observe exactly where and how the blade is cutting.
But=A0 the bottom opening for the blade in these two is behind the notch
and=A0 the blades would not then be visible during use. That kinda
implies=A0 you can see close to where the blade is, but are still
guessing how=A0 far it is actually cutting?=A0
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Notice that the front of the mouth and the rear of the large notch in
the front are pretty close together. Hard to say exactly from here, but
I would guess 3/16" from the photos. Frank says that the irons are
bedded at about 50 to 55 degrees. That means that the iron doesn't go
straight down like in an iron router plane such as a Stanley 71; it
protrudes down and forward.=A0

Suppose you are using the router plane to smooth the bottom of a groove
about 1/2" deep. Surely the iron will protrude far enough forward that
it will be easily visible from the front of the router plane.

So, the answer is, approximately, if the groove is deeper than the
distance between the mouth and the back of the large notch in the front,
you'll more than likely be able to see the leading edge of the iron from
the front.

Hope that's clear enough.

Cheers, Chuck Taylor going by geometry, not experience

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