Not to put too fine a point on it, but besides filling the gap, it also penetrates the wood surrounding the hole, and then solidifies into a sleeve custom-fit to the pin and its particular hole, so to the extent it adheres to the pin, it not only corrects the fit, it also locks it in. And because it is plastic, it resists humidity-cycle-related dimensional changes better than naked wood would. Presumably, it is as rigid as wood or more so, and therefore would conduct vibration as well or better. So besides filling gaps, it seems to me that CA _possibly_ improves the bridge and cap functionally, above and beyond just repairing looseness. All of which prompts the following questions: 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 dimensional stability might prevent cracking from ever getting started, thus preserving both the tone and the appearance. Has anyone noticed any kind of drawback to the use of CA, especially tonal. John Formsma wrote: > > What besides filling gaps would CA do? It wouldn't add mass. >
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