Correct. You have to grind flats on the two cutters so they won't interfere
with each other. The radius given by the formula is needed only where the
two "circular cutters" actually cut.
-Dave
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http://plumpe.home.mindspring.com
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"F. George McDuffee" wrote in message
...
Our machining class needs information on generating single point
(fly) cutters with involute geometry to cut spur change gears.
(snip)
== The problem is that both charts show C/C spacing distances
LESS than the specified diameter of the two circular cutters for
the form tools for larger numbers of teeth.