On Tue, 23 May 2006 07:01:52 -0700, alex.colic opined:

different groove sizes, a 1/4" and a 1/2". If it was a tongue plane
would it not make a 2 1/4" grooves?

You'd use it on stock less than 1" thick. You'd let one edge of one blade
hang over the stock. That way, exact stock thickness doesn't matter to the
tongue-cutting process. It would matter on the floor later, of course.

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