[CAUT] Shank to Hammer weight spreadsheet

[Richard Brekne]

Hi again Tim, others

    Jurgen and Jack,

    I have always found that thinning the shank raised the pitch.  I
    tried yesterday to lower the pitch by thinning the shank and
    couldn't do it.  The pitch went up every time I thinned a shank. 
    Perhaps Bluthner has a method that is different?

    Tim Coates

As a general rule, the actual specific gravity of a given shank is going 
to relate very closely to the general stiffness of that same shank. 
Hoadly says outright that specific gravity is about as good an indicator 
of wood stiffness as it gets. Given the rather uniform dimensions of a 
shank, stiffness should be fairly uniform in nearly all individual 
shanks. The variances in stiffness we see from shank to shank will 
correspond to variances in individual shank actual specific gravities. 
Given this uniformity it is no big stretch to see the parallel with 
radius weight since weight in general relates rather directly to 
specific gravity.

It would take a rather large anomaly, or extreme purposeful thinning 
over a very short length close to the fulcrum of the shank to account 
for a rouge shank whose radius weight is comparable to many neighbors 
and yet whose resonant frequency is quite a bit lower.  Otherwise... 
thinning, as is usually thought of, would no doubt raise the pitch of 
the resonant frequency... simply because the mass is lowered. Specific 
gravity will lower, as will radius weight and resonant pitch gets higher.

Wouldn't surprise me at all to find that the sorting of shanks by 
resonant frequency and shorting by radius weight were very close 
compatibles. Nearly different ways of doing the exact same thing. 
Sorting by frequency however can pick up on that one in 50 or so 
<<flabby shank>>... the ones that just have some soft spot somewhere 
what makes them unusable because of the resultant sound they make.

Cheers
RicB