I used an even simpler technique on a recent vintage Chickering to excellent effect. Flipped the piano, and made a very small scraper out of a card scraper, to scrape finish from the side of the rib, and 1/4" of the panel adjacent to the rib. No Kerfs. Then just applied a fillet with Gflex the entire length of all the treble ribs I could get to.
To make a fillet, apply a bead of Gflex to the panel and rib at the joint (masking tape has been applied to panel and rib past the fillet area). To that applied bead of Gflex, draw a radiused Popsicle stick or radiused credit card cut to a thin strip. The radius was about 1/4". Draw the radiused tool to shape the fillet. It will look like a cove. Remove tape immediately after you are happy with the fillet. I did not do from rib 4 down into the bass, because I loved the tone coming from down there as it was. Treble was non-functional before the treatment, so all the treble ribs I could get to got a fillet.
This was a finished piano, so I flipped it back over, and had immediate data on what I had changed in the treble tone. Treble tone went from non-functional, breaking up at mp, to really nice, up to 65. Over 65 I could not reach for the treatment.
Other than that, I'd strongly encourage you to learn to put a new cap on. The bridge cap and pinning is so important, this really needs to be prioritized, for tonal reasons. R-epinning, just does not cut it, especially on a 130 year old bridge.
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Jim Ialeggio
grandpianosolutions.com
Shirley, MA
978 425-9026
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Original Message:
Sent: 11-10-2020 15:58
From: Floyd Gadd
Subject: Steinway A Soundboard Treatment
I'm tearing down an 1892 Steinway A for restringing. Cosmetically the soundboard looks good, and down bearing is present right on up into the top of the treble. A firm fist thump in the middle of the unstrung board gives a nice ring.
I plan to sand, notch and repin the bridge, but I am of several minds as to how I might proceed with the soundboard.
- I can leave it as is, and hope for the best. However, the board is already almost 130 years old, and its structural integrity isn't going to last forever
- I can use epoxy to enhance the stiffness of the top surface (Fandrich, PTJ 2002)
- I can cut kerfs under the edges of the ribs, and establish a strong lasting bond between the soundboard and the ribs (Jim Ialeggio, 11-24-19 here on Pianotech)
- I can service both the top and bottom of the board, using both Jim's and Del's protocols.
I have used the first, second and fourth approaches in different situations, each time (except one) producing a satisfying result. The failure involved using the Fandrich approach, but not ensuring sufficient soundboard-rib adhesion adjacent to a soundboard crack. Following this up with Jim's approach led to successs.
Soundboard replacement is not being considered as an option.
I'm interested to see what light might be shed on the matter by posing the question here.
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Floyd Gadd
Regina SK
306-502-9103
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