reducing hammer weight

John Delacour JD at Pianomaker.co.uk
Tue Sep 9 00:35:12 MDT 2008


At 22:47 -0500 8/9/08, William Monroe wrote:

>Yes, I've done a couple samples and the difference is fairly small. 
>An 1/8" hole yields a net reduction in weight of about 1.5g.

Impossible. A cylinder of 1/8" diameter (radius (0.15875 cm.) 9 mm. 
long in a wood of relative density 0.8 (such as a heavy maple) will 
have a mass of 0.057 grams, which you would need a pretty accurate 
scientific balance to measure.


pi * ((0.15875) ^ 2) * 0.9 * 0.8 = 0.057


This would make a difference of just over a quarter of a gram at the touch.

To put it another way, 1.5 grams is the mass of a cube of water of 
side 11.4 mm, and the density of wood is considerably less than that 
of water.

Any detectable difference achieved by drilling a hole in the moulding 
will be due to the human imagination rather than to any natural law.

JD










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