String coils affect stability?

[paul bruesch]

This is just a wild, hypothetical musing... but could the tight coil provide
some minimal level of friction upon itself?  In other words, a loose coil is
not contacting the winding above it, hence it does not have the associated
friction to help keep it in place.


On 3/25/07, RicB <ricb at pianostemmer.no> wrote:
>
> Interesting.  Don is one of those guys that pays attention to this kind
> of detail... so if he says he's measured and observed some small
> difference I certainly wont discount his claim out of hand.
>
> I dont see the mechanism that would achieve this tho... at least not
> clearly.
>
> Cheers
> RicB
>
>     I certainly would not let down the tension to tighten coils.
>
>     With respect, I have measured the difference in unison stability with
>     sloppy coils. There is a small but measureable difference, after
> lifting
>     coils and tapping them down to form nice tight coils on upright
>     pianos that
>     are 50 years old and equipped with humidity control systems.
>
>     I routinely check each new client's piano by testing three pins. If
>     there
>     is no pitch drop then I accept the coils. If any of the three change
>     pitch
>     then I take the time to address the coils
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: https://www.moypiano.com/ptg/pianotech.php/attachments/20070325/f6967b08/attachment.html