[pianotech] WNG jack don't come back no more, no more, no more.....

[Mark S Burgett]

Hi Ed,
 
Sorry for the delay in answering as we are at the NAMM Show and it is quite hectic schedule at times.
 
First of all, did you check the gram resistance of the jack without the spring?  Measure at the jack tender and it should be .5 to 1.5 grams of resistance.  Next, check the gram resistance of the repetition lever (without spring).  Measure at the let-off pad and it should be 4-8 grams.  You must have an accurate dial type gram gauge with not too high range for a good reading.  I suggest a 10 gram range maximum.
 
Our springs are made of stainless steel and most pianos use Phosphorus Bronze for rep springs.
 
Hope this helps,
 
Mark

-----Original Message-----
From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org]On Behalf Of Ed Foote
Sent: Wednesday, January 18, 2012 6:13 PM
To: pianotech at ptg.org
Subject: [pianotech] WNG jack don't come back no more, no more, no more.....


Greetings, 
   Have finally found a rebuild that can use the new space age WNG composite parts.  However, the jack will NOT return under the knuckle. (Steinway B). All the geometry looks good, and  I have put more spring in than is comfortable to play, raised the rep lever until there is a noticeable gap between the height of the jack, and when I pull the jack out from under, and let it go, it will not return.  
    This is a problem I noticed on a lot of the Baldwin Renner actions years ago.  Has anybody with WNG experience dealt with this before? 
Thanks,


Ed Foote RPT
http://www.piano-tuners.org/edfoote/index.html

 

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