1890s WNG Action Geometry

[Thomas Cole]

Once I moved the capstans on an "M" for a woman who was used to a 
console with a light touch. She inherited the Steinway from her mom but 
wasn't playing it because the touch was too heavy. Because of the 
position of the plate (big gap between plate and stretcher), the action 
and therefore the capstans were further back in the piano giving it a 
heavy touch. That plus the new hammers I had hung led to moving the 
capstans and wippen heels about 8 mm. The only down side was that I had 
to shorten the blow distance more than I like, but the bottom of the 
pinblock in the bass section is very clean.

Tom Cole

Farrell wrote:

> Phil Bondi and I dove into an 1890s WNG action from a 6' 4" Knabe 
> today to try and straighten out some basic action geometry. We haven't 
> got all the kinks worked out yet, but we seem to be getting there. 
> With only a large capstan move and removal of a couple leads, we went 
> from an action ratio of over 6.0 down to 4.9. DWs went from 60+ to 50 
> and less (I know, too light) and BW in the 36 to 40g range. We have a 
> lot of work to do yet, but it seems the capstan move described below 
> has gotten us into the right ball park anyway.
>  
> Most notable was a very large capstan move that we will likely keep 
> (unless someone so kindly informs us of a potential problem the change 
> might induce). The photo below shows the original capstan in the 
> background. The forward key had its capstan moved 10mm forward and 
> 11mm lower. The middle key had its capstan moved 13mm forward and 12mm 
> lower. The second photo shows the modified wippen heel. These lower 
> positions put the capstan right on the magic line at half blow. The 
> capstan/wippen heel interface went from a traveling, grinding, sliding 
> affair and a note with 17g friction to a perfectly interfacing union 
> with no apparent sliding and a note with 9g friction. We were amazed 
> at the improvement in friction and interface movement.
>  
> This strikes me as a rather drastic capstan move. Has anyone else run 
> across an action that needed such a large capstan move? As our action 
> ratio is down to 4.9 and key ratio is down around 4.8 with the 10mm 
> forward capstan migration, we may move it back just a few millimeters. 
> But still it seems large. Is there some hidden pitfall I'm not 
> seeing? Comments?
>  
> Terry Farrell
>  
>  
>  

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