Hi, all. Speaking of CA to fill the gaps around bridge pins, let me make a few suppositions, then advance a thought. 1. Besides filling the gap, the CA also penetrates the wood surrounding the hole, and then solidifies into a sleeve which is custom-fit to the pin and its particular hole. So, to the extent the CA adheres to the pin, it not only corrects the fit, it also locks it into the bridge cap and root. 2. Presumably, the CA we choose to use is as rigid as wood or more so, and therefore would conduct vibration as well or better (is this true?). 3. Because it is a type of plastic, the CA'd bridge resists humidity-cycle-related dimensional changes better than naked wood would. 4. Therefore, besides filling gaps, it seems to me that CA _possibly_ improves the bridge and cap functionally, above and beyond just repairing looseness. So this all makes me wonder: What would be wrong with preemptively treating all the bridge pins in the whole piano with CA, before there is ever a problem, to prevent the development of loose bridge pins and related possible falseness, tuning instability, and ugly cracking? The penetration of the glue into the surrounding wood spreads the side-bearing load into a larger mass, thus reducing ovalling and improving both dimensional and therefore tuning stability. The enhanced stability might prevent cracking at the notches from ever getting started, thus preserving both tone and appearance. Has anyone noticed any kind of drawback to the use of CA, especially tonal, or is its effect always somewhere between zero and positive? Inquiringly, -Mark Schecter Oakland, CA John Formsma wrote: > > What besides filling gaps would CA do? It wouldn't add mass. >
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