Hammer bore dimension

[Phillip Ford]

>Measure the string heights, for example, at either end of the agraffe
>section, let's say hammer 21 requires 1 13/16" bore and hammer 53 (or
>whatever) requires a  1 7/8" bore.  Measure and mark the bore distance
>on the end hammers.  Now clamp them together in the same manner you
>would to gang file them.  Make sure that the strike point end for this
>group is in a straight line by butting it up against something solid.
>Now take a straight edge and using the bore markings on the end hammers
>(21 and 53) as a guide, strike a line  through the group of hammers
>which will give you point at which you will bore on each hammer.  Do
>that for each section, bass, tenor, 1st and 2nd capo.....................
>
>
>David Love
>davidlovepianos@comcast.net

Thanks.  Also, how do you determine hammer center heights?  I measure the 
centers on 1 and 88 (sometimes not the same height), with the action on the
bench,  and assume a straight 
line between them (maybe not the best assumption on a Steinway).  Other 
suggestions?  Do you have a way of measuring center height for the same 
hammers on which you are measuring string height?

Phil Ford