[pianotech] Action Centers

[William Monroe]

Dunno,

I'm not clear on how these differ from a Yamaha type butt spring.  If they
don't, I'm not sure I understand what difference the mounting position of
the hammer return spring makes (e.g. on a rail, separate from the flange, or
on the flange itself).  With the spring disengaged from the loop, you should
still be able to measure friction reliably.  I'm also unsure how the heavier
hammer would not present greater inertia, regardless of springs.  So, I
guess I'd say yes, I'd use the same protocol.  If you could elaborate a bit
on this arrangement, maybe I'll change my mind.  ;-]

Always willing to be educated.

William R. Monroe

On Thu, Apr 30, 2009 at 8:53 PM, <wimblees at aol.com> wrote:

> Bill
>
> I agree with your method for "ordinary" flanges. But Matthew is working on
> spring loaded flanges, where the resistance is only in the strength of the
> spring, not the weight of the hammer. Would you still go for more resistance
> on the heavier hammers?
>
> Wim
>
> -----Original Message-----
> From: William Monroe <bill at a440piano.net>
> To: pianotech at ptg.org
> Sent: Thu, 30 Apr 2009 9:24 am
> Subject: Re: [pianotech] Action Centers
>
>  Different strokes.  If I measure with a gram gauge I'll taper the
> friction, higher in the Bass (~5g), lower in the Treble (~3g).  Usually I
> measure with the swing test, aiming for the same number of swings Bass to
> Treble - about 6 swings, depending upon the season/humidity.  When I taper
> the gram friction readings, I'm essentially trying to produce this even
> swing result.  Heavier hammers with more inertia will produce more swings
> than a lighter hammer for the same gram friction.
>
> William R. Monroe
>
> On Thu, Apr 30, 2009 at 12:59 PM, <wimblees at aol.com> wrote:
>
>> There should not be any difference between bass and treble. I don't know
>> what an acceptable reading would be, because I've never measured one. As I
>> said, test about a dozen flanges, and take an average.
>>
>> Wim
>>
>> -----Original Message-----
>> From: Matthew Todd <toddpianoworks at att.net>
>> To: pianotech at ptg.org
>>   Sent: Thu, 30 Apr 2009 5:31 am
>> Subject: Re: [pianotech] Action Centers
>>
>>      When I use the gram gauge, what is an acceptable reading?  Will it
>> vary from bass to treble?
>>
>> ***TODD PIANO WORKS*
>> Matthew Todd, Piano Technician
>>
>
>
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