new Baldwin Pin Torque, was PianoTechList Comments

[Susan Kline]

Hi, Brian

>Is it possible for perfect cylinder (as in the
>ideal tuning pin hole) to become larger as it
>deforms?
>
>My little brain keeps saying "smaller", "tighter
>fit".

I don't picture the hole as a perfect cylinder, Brian.
As soon as the ends of the board bow downward, the
top becomes longer than before, and the tops of
the holes spread, while the bottom of the holes
compress. But if the pins don't reach to the bottom
of the holes, but instead are more influenced by
the top?

You see the vice versa, don't you? Bow the ends of
the board up, the top is in compression, and the holes
get smaller at the top but bigger at the bottom?

Wiser heads, is this what happens?

Well, if we imagine it with something stretchy, like bread
dough? I'm assuming that the wood is at least a little
stretchy; otherwise the pinblock would just break.

Susan