[pianotech] Brumbach Rebuild

[Paul McCloud]

Hi Marcel:
    Yes, looking at this thing brings up many thoughts.  It seems that the length of the whippen (wippen) is too long.  That would account for the excessive angle of the jack/knuckle and off-center jack tip to letoff button.  And explain why the capstans were moved.  Joe Garrett has offered to lend me a couple of Brahmbach wippens to try to re-establish the geometry as it was originally.   Also, I have not yet got the go-ahead for the work, so I said I'd take him up if I get the job.  The piano isn't at my place, so some of the measurements will have to be made there at the home.  The trouble is, the original knuckles were probably the pear-shaped kind, and those are not around anymore (am I wrong?).  It makes me wonder why the rebuilder used those wippens.  
    Paul McCloud
    San Diego


----- Original Message ----- 
From: Marcel Carey 
To: Pianotech List
Sent: 11/01/2010 8:11:21 PM 
Subject: Re: [pianotech] Brumbach Rebuild


Just looking at picture #3, I see that the wippen rail seems to be leaning towards the front of the keys. I would probably start by making it straight (the wippen flanges should be kind of perpendicular to the string plane). This would open up the action spread and by the same time would make the jack more perpendicular to the hammer shanks at rest.
It's something that struck me just by looking at the rails.


Marcel Carey

> Date: Mon, 1 Nov 2010 19:48:50 -0400
> To: pianotech at ptg.org
> From: jonpage at comcast.net
> Subject: Re: [pianotech] Brumbach Rebuild
> 
> Also take note of the alignment of the shank over the rear of the
> rep lever. If they are not aligned, consider moving the stack front
> or back on the frame to reposition the hammer to the string thus
> raking the shank back centered over the rep lever.
> 
> My guess is that if you increase the spread and move the stack
> further back on the frame (distally) the ML will fall into place.
> -- 
> 
> Regards,
> 
> Jon Page
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