Relocating Knuckles

Phillip Ford fordpiano@earthlink.net
Fri, 21 May 2004 16:28:28 -0700 (GMT-07:00)


PF wrote:

> >...So, the knuckle location had to be changed...extracting the
>hammers and rehanging them
> >on new shanks and flanges with a different knuckle location.
>This was a
> >lot more money than 2 or 3 hours of my time and a set of knuckles.
>
>

Jon Page replied:

>Why not put identical weight hammers on new shanks.
>(Unless the shank length is not generic).
>This way you have a prehung set for some other job.
>

Jon,

1.  Your prehung set would have to be bored at the same length as that 
of the other piano that you intend to put them on.  With a Steinway there's 
a good chance that that wouldn't be the case.

2.  They liked the sound of the piano with the existing hammers.  There's 
more to determining the sound from a given hammer than just its weight.  In 
my opinion it would be a dicey proposition taking off a known quantity in 
the form of hammers that were producing a sound they liked, and putting on 
an unknown quantity in the form of a set of new hammers, and trying to get 
a sound from them that they liked (and not causing comparisons with the 
previous hammers - it doesn't sound like it did before, what happened?).

3.  The hammers gave a 1/2 high Strike Weight (SW), to use Stanwood 
terminology.  In my experience the action will never feel right (it will 
feel heavy or sluggish on hard or fast play) with hammers that heavy on a 
15.5 mm knuckle location, even if you can work all the geometry out so that 
you get a decent overall ratio, reasonable touchweight, and no excessive 
leading.  So, something would have to be done anyway.  You couldn't just 
take those prehung hammers off and put them on another piano.  You would 
either have to move the knuckle location or cut down the hammer.  Unless 
you have some sort of jig for tapering the hammers with them installed on 
the shanks (I've heard that Roger Jolly has such a jig, but I don't) then 
you would have to extract them anyway to reduce their weight.

Regards,

Phil Ford



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