New board with cut-off for Steinway XR

[Greg Newell]

Ron,
         Thanks for sharing these pics and your 
description of the process. I hope you remember 
to share both yours and the owners perception of the final result. Look great!

best regards,
Greg Newell



At 08:08 AM 4/15/2007, you wrote:
>Hi all,
>
>We're currently rebuilding an interesting little 
>piano, a 1925 Steinway XR grand (this piano has 
>a model M plate) with an American Black Walnut 
>art case and an Ampico reproducer.
>
>Our brief from the owner was that he wanted it 
>rebuilt to original spec, ie. without any 
>modification bells and whistles, since the piano 
>was in original condition when he purchased it. 
>The board wasn't too good from a visual and 
>tonal perspective so we decided to replace it.
>
>The first plan was to build a compression 
>crowned panel to keep it totally original. 
>However, with only ten ribs and no bass corner 
>cut-off, I decided that the board might be 
>better made as a hybrid with crowned ribs and a 
>moderately dried panel to 6%. So our purest 
>ideals didn't last for long. I made a test 
>soundboard strip of the longest rib (1200 mm) 
>and found that it was very weak on account of 
>the long span, with a quite high crown of 14 mm 
>in the middle of the rib. For the sample, the 
>rib-top was machined with a 60' radius. The 
>dried test panel was glued to the rib with the 
>rib-top-surface held at the same 60' radius. 
>After panel re-hydration the test strip crowned 
>a further 5.5 mm. This level of crown is likely 
>to cause all sorts of packing problems with the 
>rear aliquot blocks. Furthermore, I just don't 
>like the middle-order ribs being so long and 
>weak. So on Thursday night I took one of my 
>laminated cut-off pieces and laid it in the 
>case, just to have a look at possibilities. It 
>made so much sense, and I can't see the point of 
>re-boarding a case with an original design board 
>which may fail in a decade or so on account of poor design.
>
>So I called the owner in for a discussion. After 
>explaining my thinking, he agreed that since we 
>could cover the bass corner with the soundboard 
>panel, thus hiding the evidence, and since the 
>player gear will fully block visual access to 
>the underside of the board, we decided to press 
>ahead and fit one of my laminated cut-offs to 
>the case. I'm still going to make the board as a 
>hybrid supported unit, to keep something of the 
>original design philosophy of the original maker 
>intact. With the cut-off, the two longest ribs 
>which were 1200 mm long will now be around 850 
>long. This will be a much better result, since 
>the middle-order ribs will be stiffer than those 
>in the bass and the mid-board crown will now be 
>much less on account of the shorter span, which 
>will make the setup prior to stringing a lot simpler.
>
>Here are some image links. I worked a bit over 
>the weekend and got the cut-off fitted.
>
>Here is an image of the cut-off with the rib 
>notching machined before fitting it to the case.
>http://members.optusnet.com.au/ronovers/steain.bd6.jpg
>
>Here is the cut-of clamped in place with the 
>ribs stock sitting in the notches for checking 
>prior to gluing to cut-off in place.
>http://members.optusnet.com.au/ronovers/steain.bd7.jpg
>As you can see, the cut-off greatly improves the 
>structural layout and soundboard-area distribution.
>
>Here is an image of the cutoff glued and clamped into place.
>http://members.optusnet.com.au/ronovers/steain.bd8.jpg
>I was feeling a bit ho-hum about this piano with 
>the original board concept, but now it will be 
>very interesting to hear the end result.
>
>Sorry I haven't contributed to any list 
>discussion lately, since I've had a whole lot of other stuff to attend to.
>
>Regards,
>Ron O.
>
>--
>OVERS PIANOS - SYDNEY
>    Grand Piano Manufacturers
>_______________________
>
>Web http://overspianos.com.au
>mailto:ron at overspianos.com.au
>_______________________

Greg Newell
Greg's Piano Forté
www.gregspianoforte.com
216-226-3791 (office)
216-470-8634 (mobile)

2003,04,05 & 06 winners of
Angie's List Super Service Award
-------------- next part --------------
An HTML attachment was scrubbed...
URL: https://www.moypiano.com/ptg/pianotech.php/attachments/20070415/62d70bbe/attachment.html