[pianotech] wooden click at letoff?...reprise

[Douglas Gregg]

Jim,
I think John Parham is on to it. It is likely the sostenuto action. I
have a Petrof grand with a similar problem in two notes in the middle
of the keyboard. If I pulled the action out a hair, it disappeared. It
was hitting the sostenuto rod or something in the sostenuto. I can't
remember exactly now. It was adjustable.  It was tough to find because
you can't see anything back there. Good luck.

Doug Gregg
Classic Piano Doc
Message: 9
Date: Sat, 05 Jan 2013 01:00:07 -0700
From: <johnparham at piano88.com>
To: pianotech at ptg.org
Subject: Re: [pianotech] wooden click at letoff?...reprise
Message-ID:
        <20130105010007.f1fd8b108a58a93f763c4cd7f53850a9.52a9663dfb.wbe at email03.secureserver.net>

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Jim,

If it's a grand with a sostenuto rod, the damper upstop rail could be
set so high that the damper underlevers are hitting the sostenuto rod.

-John Parham


> -------- Original Message --------
> Subject: [pianotech]  wooden click at letoff?...reprise
> From: Jim Ialeggio <jim at grandpianosolutions.com>
> Date: Fri, January 04, 2013 9:19 pm
> To: pianotech at ptg.org
>
>
> An unsuccessful followup on this post from November...
>
> Got back back to this 10 year old Renner action with a recalcitrant
> click at and after letoff. There are now 2 of them, F1 & G#1.
>
> I had thought originally that the sound was from the shank assembly, so
> I appeared armed and ready for knuckle changing or shank changing.
> Removed and re-glued both knuckles, then set about putting in a Dampp
> Chaser. Finished the DC and  listen for the click...still there...rats.
>
> Swapped a nearby quiet shank, and carefully regulated the swapped shank
> so I got the full and proper letoff/aftertouch event. The swapped shank
> produced the same click as the original shank. So my original assumption
> that the shank was the culprit was too hastily decided. Started looking
> around.
>
> -F1 had an anamolous geometry issue. JAck was smacking the jack stop
> felt, while all the other notes including  the other offending note,
> G#1, were just fine at the jack stop felt. Removed half the jack stop
> felt from F1...click remained. The jack toe is definitely set at a lower
> angle than the other whips, and jack travel is more than the other
> whips, but it doesn't seem to be the source of the sound, as I removed
> enough felt to leave some clearance.
>
> -looked for flange issues on two whips (turbo). G# cracked on one side
> of the flange, but F1 fine.
>
> -Then in messing around, I lifted the dampers with the pedal, and tried
> both notes again.  This time the click on both notes disappeared! I
> suspected a loose lead in the damper levers. Took out the action played
> with the offending damper levers, but as time was way past up, and had
> to clear out, I couldn't remove the levers to check the weights on this
> visit. In moving the levers there was no noise, but I don't think that
> is a fair indication of anything, since connection to the back of the
> key is their path to the click amplifying keyframe/keybed...though there
> is a felt interface beween damper lever and key which I would think
> would mitigate at least some noise.
>
> Question?...does this sound like the modus operandi of loose damper
> lever weight?  Why would damper lever weights click at and after letoff?
> Let off does impart a kick to the key, which might rouse the offending
> leads, but I'm still somewhat sceptical...but running out of ideas. I
> scheduled a DC followup tuning in 3 weeks, so I have an imminent rematch.
>
> Jim Ialeggio
>
>
>
>
>
> --
> Jim Ialeggio
> jim at grandpianosolutions.com
> 978 425-9026
> Shirley Center, MA