[pianotech] Piano Key Leveling

[Keith McGavern]

Tom,, List,

While it may or may not be true that a crowned keyboard gives the  
appearance of being level from a distance, that is hardly the reason  
for doing crowned key leveling in Steinway grand pianos. The following  
reasons have been presented already on the Pianotech List by me, and I  
post them again for your perusal.

This is directly from the Steinway & Sons Technical Service Manual  
that I had have in my possession since 1992.

------
Bedding the Keyframe to Keybed
Background: Steinway utilizes a keybed which is shaped and planed in  
such a way that it provides the keyframe with a solid support  
structure and minimal friction.

Features:
1) The front lip of the keybed (1/2" approximately), which contacts  
the keyframe is crowned so that its center is approximately 1/32"  
higher than the ends.
5) The front rail of the keyframe is reverse crowned so that the  
center of the front rail is approximately 1/32" lower than the ends.  
This is done to ensure stability at the front rail. There should be no  
gaps along this line of contact.
(page 11)
-----

This clearly shows that when the keyboard is held in place with  
keyblocks, leveling the keys correctly should follow the line of that  
crown as recommended by Steinway and should not be leveled flat.

Now interestingly enough, and which had not been mentioned before in  
this thread, crowned key leveling also applies to Steinway verticals  
as well. (p80)

The real question remains: "When did the Steinway company actually  
implement this crowned feature in its pianos?" I have physical records  
that indicate crowning the key level has been published in their  
service manuals since somewhere in the 1960s'. Prior to that time is  
unknown by me.

Sincerely,

Keith

On Jun 27, 2009, at 4:56 AM, Tom Servinsky wrote:

> Just returning from a trip and noticed a lot of interest in the idea  
> of crowned key leveling. On my many trips to the Steinway factory,I  
> was always posed that as my first question. Why the need for the  
> crown keyboard? I've heard one reason after another, none which made  
> any sense. That was until Eric Schandal was finally kind enough to  
> give me the real poop.
> Crowned keyboards look level from a distant. Level keyboards look  
> concave. Plain and simple.
> They've done it that way for years and I'm sure they'll continue to  
> do it for years to come.
> Remember...there's the wrong way, the right way, and then there's  
> the Stein--way.
> Tom Servinsky
> ----- Original Message -----
> From: Keith McGavern
> To: pianotech at ptg.org
> Sent: Sunday, June 21, 2009 10:54 AM
> Subject: Re: [pianotech] Piano Key Leveling
>
>
> On Jun 21, 2009, at 9:36 AM, Gerald Groot wrote:
>
>> One question is, was this level board meant for the older pianos  
>> that called for possibly more crown in the middle or perhaps more  
>> crown than what today's pianos call for?
>
> Gerald,
>
> The only piano I've heard of that calls for a crown in the middle is  
> Steinway grands.
>
> Keith

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