Hexagonal Hammer Shank

[James Ellis]

Ron, 

The moment of inertia has nothing to do with stiffness.  It has to do with
where the mass is.  The inertia of the shank is a tiny fraction of the
total inertia of the shank and hammer system.  The hammer head is where the
big moment of inertia is.  The stiffness of the shank is important so that
the hammer head does not wiggle and wobble.  At the same time, a heavy
shank would put mass where we don't want it, but even in the shank, it
depends upon where the mass is.

If we are interested in stiffness, I think the best thing to do is to
measure it.  That's what I plan to do, when I get time.  There are just too
many variables in a stick of wood to try to calculate it.

Jim Ellis