[pianotech] Jack and Damper Spring Tension Targets

[Floyd Gadd]

Hi David,

No, I have already adjusted the pinning so that the jack will fall under its
own weight when not influenced by the spring.  But I read in the archives
(Don Mannino's January post, I think) that some pianos were manufactured
with excessively strong jack springs, and this piano seems to have symptoms
that point in that direction.  Should I identify that the tension is indeed
excessive, the only I solution I can think of would be to replace the jack
springs with something more appropriate. One does, of course, eventually
come up against the law of diminishing returns, but I would like to at least
be skilled in evaluating the variables that face me as I seek to diagnose a
problem action.

Floyd Gadd



David Ilvedson wrote:

You are actually reading the jack spring tension and then repinning for
correct tension?

David Ilvedson, RPT
Pacifica, CA  94044

----- Original message ----------------------------------------
From: "Floyd Gadd" <fg at floydgadd.com>
To: pianotech at ptg.org
Received: 7/28/2009 8:47:04 PM
Subject: [pianotech] Jack and Damper Spring Tension Targets


>List,

>I'm still exploring the regulation of my 1966 Heintzman console.  The jack
>return is REALLY snappy.  I'm trying to identify an appropriate target for
>the jack spring tension.