Dave, Thanks for your note. The crack you saw has no bearing at all on the sound of the piano. This is a cosmetic flaw only, and can easy be repaired while it is in your shop. In Kawai pianos the strength of the piano comes from the inner rim and beam structure, along with the iron frame. The outer rim is made from a softer wood, and although the height of the outer rim adds a little rigidity to the structure, this does not contribute to the support of the soundboard or the production of tone. Our inner rim is quite thick (thicker than the combined inner and outer rim in some pianos) and made from a very hard wood, so this is where the strength and rigidity of the structure comes from. Kawai even makes a "Crystal" piano where the outer rim is made from Plexiglass and is bolted to the inner rim. These pianos are just as stable and strong as the standard pianos, even though there is what could be called a very serious "crack" between the inner and outer rims! The inner rim on this GS-70 was made with all laminations in one direction, while the outer rim was made with cross-laminated wood. In dry areas Kawai found that the inner rim on some pianos made this way would shrink up a little, and the tension between the inner rim and the cross-laminated outer rim would cause a crack to appear at the bottom. These normally only travel up into the rim a short way (an inch or so), and the integrity of the rim structure is not affected. We recommend that the crack be repaired by turning the piano over and filling it with thin epoxy. Using a heat gun to pre-warm the wood and also to warm the epoxy will help it to penetrate into the crack more readily, and will help the epoxy to bond with the wood fibers. The bottom surface of the rim should then be sanded or scraped smooth and refinished with black lacquer. When pianos are still within the warranty period, Kawai will pay for these repairs. Don Mannino RPT, Manager Kawai Piano Technical Support, US and Canada www.kawaius.com dmannino@kawaius.com
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