A tenor bridge conversion

[Stéphane Collin]

Hi list, hi Ron.

Just one stupid question for Ron.
Ron, I truly appreciate your work and effort in piano improvement.
But reading this, one question comes to my mind : 
do you really believe that Bechstein engineers were not aware of the % of breaking strength of the tenor strings of their pianos ?  I suppose not.  So the next question is : why the hell those educated people did chose to implement such a design (the tension drop in low trebble bridge) on such an expensive piano ?
Just wondering.

Best regards.

Stéphane Collin.
  ----- Original Message ----- 
  From: Concert Piano Service 
  To: Pianotech List 
  Sent: Monday, January 22, 2007 8:40 PM
  Subject: Re: A tenor bridge conversion




  On 22-jan-2007, at 1:52, Ron Overs wrote:


    Hi all,


    I've just loaded a couple of images onto my webspace which show the layout for a tenor bridge conversion of a Bechstein model C grand, and an image of the new tenor bridge in place prior to stringing.


    Here is an image link taken at the layout planning stage;


    http://members.optusnet.com.au/ronovers/bech_c_tenor1.jpg


    Here is an image link, taken last Friday which shows the finished tenor bridge in place, awaiting strings.


    http://members.optusnet.com.au/ronovers/bech_c_tenor2.jpg


    The original Bechstein C (circ 1953) was one of the most outstanding examples of a poor scale I've ever measured in a mid sized grand. The tension dropped down to around 18% at note E20 (the lowest note on the long bridge). To rectify this problem, a new tenor bridge was designed from the first original trichord plain note, E20, up to note D#31. The new lowest plain-strung trichord is at a respectable tension of 36%. This will transform the model C from one of the worst crosses in the business, improving it to the point where it is about equivalent to the cross of a model D Steinway (in terms of percentage of tension deviation - the lower the deviation the better the tuning stability). Should have it strung and playing in a couple of weeks.


    Ron O.








  Hi Ron,
  I have a question :


  You cut off the treble bridge in the tail. Did you do that because that last part of that treble bridge is so close to the rim?
  I worked on a brand new Bechstein C and I noticed that those first treble notes (nr 21 to appr. nr 30 sounded weird and were difficult to voice correctly, as usual).
  I also wonder what kind of string thickness you use on that new bridge you built. Do they get thicker in size because they are shorter?




  friendly greetings
  from
  André Oorebeek


  Antoni van leeuwenhoekweg 15
  1401 VW Bussum
  the Netherlands


  tel : 0031 35 6975840
  tel : 0031 652388 008


  where music is, 
  no harm can be



-------------- next part --------------
An HTML attachment was scrubbed...
URL: https://www.moypiano.com/ptg/pianotech.php/attachments/20070122/b33c80af/attachment.html