[pianotech] key leveling with a curve

[Paul McCloud]

Hi, Gene:
	If you bore the hammers so that the hole is closer to the crown of the
hammer, then you are able to compensate for a lower string plane.  Take a
look at the bore distance in the bass.  Since the string plane must be
higher in the bass, your hammers are bored differently in that section.  It
is also not uncommon to regulate the hammer height a little different for
each section of the piano.  The hammer height might be lower in the treble
in your example.  So the distance the hammer travels is going to be the
same.  No need to change the dip to compensate, since the hammer travel is
going to be the same.  If you do change the dip and aftertouch to
compensate, the pianist is going to notice that.  You may want to raise or
lower the hammer line,  and maybe even allowing the hammer line to be a
little uneven, to achieve a consistent dip and aftertouch at the key.  It
is a matter of which one you want to take priority- consistent
dip/aftertouch or an even hammer line.  There could be arguments for either
case.
	I hope that helps.
	Paul McCloud
	San Diego


> [Original Message]
> From: Gene Nelson <nelsong at intune88.com>
> To: <pianotech at ptg.org>
> Date: 10/13/2010 7:50:54 AM
> Subject: Re: [pianotech] key leveling with a curve
>
>
> :
> >
> >>...I can see the argument for mimicking the string plane curve
(maybe)...
> >
> >
> > Well, can you or can't you?  And if you can, how and why?  I can send
you 
> > a few sample Steinway strike height curves if you like and you can tell
us 
> > how on earth they can be mimicked in the key levels.
> >
> Mabye I am not getting the big picture and that is typical for me.
> But - if the string height becomes lower toward the treble, it seems that
if 
> the hammer line remains level there will be an issue with key dip - it
will 
> deminish as the blow distance deminishes.
> The question is do you regulate that way or do you try to keep dip
constant? 
> If you keep it constant would it not be reasonable to have a key level
that 
> was higher in the center than the ends?
> Gene