keyboard levelling

[justpianos@our.net.au]

Hi List,
This question is obvious to me, but I don't know the history of innovation in 
piano design.
Has anybody tried a balance rail pin which screws in and out of the balance 
rail, with micro-thread like tuning pins, to adjust it's height.
A flange at the bottom on which sits one felt punching and then the key, 
which goes up and down when adjusted from the top. Has to be quicker, easier 
and more accurate.
Bruce Browning-The Piano Tuner.


Isaac Sadigursky <irs.pianos@earthlink.net> said:

> Hi,everybody! regarding leveling the keys i'm surprised nobody had 
mentioned the possibility of leveling them "by ear",just the way blind 
technicians do. when straightedge or my favorite L-shaped aluminum
>  is covering 1-1.5 octaves,just tapping the keys from the buttom will 
produce different sounds depending on the gap and then it is your judjment 
what thickness paper punching to insert. I had observed this technic in one 
of the convention classes for blind tuners years ago. It woyks! best of luck. 
isaac
> P.s> the list is very addictive.. i'm thrilled to see all familiar names 
and appreciate wealth  of information and knowledge. Happy Thanksgiving to 
everyone!
> 
> ----- Original Message ----- 
> From: Stéphane Collin 
> To: Pianotech
> Sent: 11/22/04 5:55:34 AM 
> Subject: Re: keyboard levelling 
> 
> 
> Hello Quentin, David and list.
> 
> Strange, I find it much easier to appreciate a straight line in the keys 
when viewed from the side of the keyboard, than to appreciate the individual 
distance from the keys to a stick placed above them (certainly if that 
distance is small).  Also, only by eye can I pound three informations : the 
alignement of the underside of the fronts of the keys (supposed of course 
that they are perfecly evenly cut, which is nearly always the case), the 
alignment of the underside of the keytops, and the alignment of the upside of 
the keytops (which, if ivory and old, can have altered thicknesses due to 
wear which would induce some severe leveling errors when regulated with the 
stick).
> 
> And, when it comes down to less than 0.16 mm difference between the level 
of adjacent keys (0.08 mm is the thickness of the smallest balance rail 
punchings I use, and I suppose here that the balance hole is approximately in 
the middle of the key length), which difference I'm sure anyone can see, I 
believe that the discrepencies in the other parts of the action plus the 
discrepencies in string height and the discrepencies in the apparent bore 
distance of the used hammers are all of greater consequence (and concern) to 
the regulation.  
> 
> Best regards.
> 
> Stéphane Collin.



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