[pianotech] Wandering Capstan Screws

[Ron Nossaman]

On 12/4/2011 10:44 PM, David Skolnik wrote:
> Ah, thank you Buddha.
> though you may mean
> to mock me
> your reply made
> me laugh
> deeply
> and think

No mocking intended, but there is still a pretty big hole in the 
concept. Thinking was the intent. We tend to make quick assumptions and 
start generating supporting details, when the assumptions don't really 
connect with observation.

So far, the only difference mentioned between this installation and 
others that don't manifest the problem is that the others used action 
cloth and this one felt. The felt, I'd expect, would wear an indentation 
from the screw more deeply than the cloth, so would show a more 
effective thickness change between the screw top and wippen bottom with 
a slight position change, which I'd also expect would more with felt 
than cloth. The randomness of the change indicates it's not a humidity 
induced thickness change, but it could still be a  slight repositioning 
of an indentation over the screw that's different on each key. I'd 
suggest action cloth mounted on the wippen bottom and replace the screws 
with capstans.

Ron N