What's all this I hear about Inertia ?

[David Love]

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.