balance hole reamer?

[John Delacour]

At 17:43 -0400 20/3/08, A440A at aol.com wrote:

>  JD writes:
>
><< Yes.  Now answer me this :  The picture below shows keys from grand
>pianos by three excellent makers.  In all of them the lowest contact
>with the balance pin is made over 1mm from the bottom suface of the
>key. Why? >>
>
>I would assume that it is to prevent wood from splitting at the edges of the
>hole.

Oh, I've never seen that happen.  Why do you think they stopped 
making keys like that about 1900, not to mention 101 other things 
they stopped doing, usually for the simple reason that they lost the 
plot -- and haven't yet found it again.

>  And it seems that if you push a conical burnisher in from the bottom,
>you are raising the contact edge even higher up in the hole.

I have never had to use a burnisher on such keys.  Besides, there's 
conical and conical, and there's also anal retention!

JD