[pianotech] New custom agraffe design

[Encore Pianos]

Hi Ron:

 

Nice pictures and info.  Thanks for sharing.  

 

Are your agraffes something that you might be making available for other
rebuilders?

 

Do my eyes deceive me, or is the steel plate sandwiched between two layers
of brass?

 

Will Truitt

 

From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf
Of Overs Pianos
Sent: Wednesday, June 13, 2012 8:58 AM
To: pianotech at ptg.org
Subject: [pianotech] New custom agraffe design

 

Hi all,

 

I mentioned in a recent post that we were planning to manufacture special
agraffes for our pianos, since I have finally had enough of brass agraffes
which sometimes are capable of producing noise aplenty, at times even before
an instrument leaves the workshop.

 

It took a while to get a result, but below is an image-link which shows a
sample of the first batch of our special agraffes made from SAE 4140 alloy
steel (this stuff is typically used for making truck drive axles). This
sample has been hand polished and cleaned ready for Electroless Nickel (EN)
plating. The plating is necessary for two reasons;

 

1) To provide corrosion resistance

 

2) To provide a suitable low friction bearing surface, since steel on steel
is not good for friction.

 

The image of the agraffe can be found at;

http://www.overspianos.com.au/ove.agraffe.jpg

 

These agraffes feature an internal-hole profile which looks something like
the hole of a doughnut, as a string termination shape. Provided that the
string approach angle doesn't exceed 10 degrees, the string will always have
clearance with the agraffe body, and will only contact the agraffe at the
'internal doughnut'. I'm really looking forward to hearing the first of
these in a month or so.

 

The first batch will be fitted to a model D rebuild we're finishing off for
Sydney Conservatorium of Music, and another 210 cm grand piano we're
rebuilding, with extensive modifications, for sale.

 

I'm really looking forward to getting the 210 finished, since it will be
fitted with the custom agraffes, a new capo and counterbearing system,
comprising of a new V bar capo, and a V bar counterbearing bar 25-30 mm
behind the capo (both V bars are hardened and EN plated). Also included is a
6-note tenor bridge (all bichords) with the agraffes relocated to preserve
the hammer strike ratio, a new bass scale design, an action ratio revision
and the inclusion of a set bolt at the bass-side-X, since it was left out of
the original instrument - likely as a cost cutting measure. Overall, there
won't be much of the original Young-Chang Steinway model B clone left in the
piano. It will pretty much be our tonal character inside a 210 case (hence
the name change to Overs-Beale). We're planning to sell it for around A$60K
(FOB). A description of this piano, written before the rebuild commenced,
can be found at;

http://www.overspianos.com.au/BG7.htm

 

A screen-shot which shows %-break scaling charts for a Steinway B, the
original clone and our re-design can be found at;

http://www.overspianos.com.au/7ftgrd.tens.snpsht.jpg

 

An image in the bottom RH corner of the screen-shot shows overhead images of
a Steinway B and the original Beale BG7 piano before the rebuild started.
The similarity in the scale is obvious. The Beale case is wider at the back,
which is no advantage, despite the fact that the current crop of designers
can't resist widening the back. Generally the change only results in the
differing distances of the bridges from rim to be even worse than
previously.

 

I'll be adding in-progress images of the new rebuild to the website soon, in
our 'pianos for sale' section.

 

Ron O.

 

-- 

OVERS PIANOS - SYDNEY

   Grand Piano Manufacturers

_______________________

 

Web http://overspianos.com.au

mailto:ron at overspianos.com.au

_______________________

 

A web page with images of recent work and almost-audio-CD quality mp3 sound
files of the Overs piano can be found at;

http://overspianos.com.au/more_info.htm

 

So put on your headphones, plug them into your freshly restarted computer
and sit back to over 20 minutes of pure piano.

 _______________________

 

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