What's all this I hear about Inertia ?

[Fenton Murray]

 > Curious as to how you got  "an action with the same hammers, ratio, and
    >BW, but different leading".  If you change the leading, then you change
   > the BW.
Ric,
With Assist Springs. If the assist springs take 18 grams off the back of the 
key, that moment value as it relates to key ratio may be removed in lead 
from the front of the key. Nothing is changed except an amount of lead is 
replaced with a spring. Now, a before and after comparison can be made of 
the 'fell' of the action. BW will be the same, perhaps friction will be 
reduced slightly by less weight on the capstan. All of these experiments on 
my part were simply my mistakes that required a re-do, best opportunity 
there is for knowledge.
Fenton

----- Original Message ----- 
From: "David Love" <davidlovepianos at comcast.net>
To: "'Pianotech List'" <pianotech at ptg.org>
Sent: Monday, October 06, 2008 1:17 PM
Subject: RE: What's all this I hear about Inertia ?


> Then we're defining ratio differently (not to speak for Fenton).  Changing
> the front weight has nothing to do with the action ratio.  I believe what
> Fenton referred to was replacing lead with help from the assist spring.
> Then you do have the same hammers, ratio, BW, different leading, because 
> the
> assist spring takes the place of some of the lead.  The action would
> therefore have lower inertia.
>
> David Love
> davidlovepianos at comcast.net
> www.davidlovepianos.com
>
> -----Original Message-----
> From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On 
> Behalf
> Of Richard Brekne
> Sent: Monday, October 06, 2008 1:56 PM
> To: pianotech at ptg.org
> Subject: What's all this I hear about Inertia ?
>
> Grin... if you change the amount of FW,  then you change the Ratio and
> you no longer have "an action with the same hammers, ratio, and
> BW, but different leading" You have an action with both different
> leading and different ratio. Moreover, the bulk of commentary along
> these lines so far would seem to support the claim that assist spring
> compensating for same BW after a change in FW will not be able to create
> the <<same feel>> (however one arrives at what that might eventually be)
>
> Cheers
> RicB
>
>
>    Uh...by using assist springs.  Seems fairly clear.
>
>    David Love
>    davidlovepianos at comcast.net
>    www.davidlovepianos.com
>
>
>    Greetings.
>
>        On assist springs, I think they can make a bad action better by
>        allowing the removal of excess key lead, not the right way to fix
>        things. But, fooling around with these things I was able to 'feel'
>        the same action with different amounts of key lead, . An old 550
>        Kawai had a nice action until I unhooked the assist springs and
>        added lead.
>        Fenton
>
>    Curious as to how you got  "an action with the same hammers, ratio, and
>    BW, but different leading".  If you change the leading, then you change
>    the BW.  That is to say unless you changed the leading but kept the FW
>    constant.
>
>
>
>
>
>