[link redacted at request of site owner - Jul 25, 2015]

Killer Octave Question

John Hartman [link redacted at request of site owner - Jul 25, 2015] [link redacted at request of site owner - Jul 25, 2015]
Sun, 13 Apr 2003 17:23:04 -0400


Del,

I think we were talking about the crown of the bridges not the ribs.

John

Delwin D. Fandrich wrote:
> ----- Original Message -----
> From: "Greg Newell" <gnewell@ameritech.net>
> To: "Pianotech" <pianotech@ptg.org>
> Sent: Saturday, April 12, 2003 8:02 PM
> Subject: Re: Killer Octave Question
> 
> 
> 
>>>If the crown was created by being deformed for many years we would see
>>
> all
> 
>>>piano makes with this feature. If this were so they all would have
>>
> crowned
> 
>>>bridges. But clearly some makes have crown and others don't.
>>
>>Good point! I haven't seen enough of them to make this comparison.
> 
> 
> Not necessarily. It would depend on how rapidly the original board lost its
> compression-crown. If the original board was set up (in NY or wherever) on a
> dry day with a fair amount of string bearing and then sent to a relatively
> humid climate it would deteriorate quite rapidly. There would not be enough
> time for the ribs to take on a set themselves. On the other hand if the
> board were originally set up on a humid day and with light string bearing it
> would last considerably longer. As to whether this would be long enough for
> the ribs to take on a set or not I can't say. I have pulled ribs off of old
> Steinway boards that indicated some slight amount of curvature. (I would
> call 1/8" curvature on a long rib "slight.") Both up and down. I'm not
> prepared to say just where this curvature came from. Steinway has
> traditionally installed flat ribs. While it is certainly possible for a flat
> rib to warp though it would be unlikely for three or four adjacent ribs to
> warp in the same direction.
> 
> Del
> 
> _______________________________________________
> pianotech list info: https://www.moypiano.com/resources/#archives
> 
> 


-- 
John Hartman RPT

John Hartman Pianos
[link redacted at request of site owner - Jul 25, 2015]
Rebuilding Steinway and Mason & Hamlin
Grand Pianos Since 1979

Piano Technicians Journal
Journal Illustrator/Contributing Editor



This PTG archive page provided courtesy of Moy Piano Service, LLC