The important thing to realize is that thin CA is useful when "doping" an old, fully strung piano. I only use a few drops at each pin. I have seen posts recommending soaking alot of CA into the pinblock. One of those posts mentioned an unintended result of CA dripping out onto the keybed or customer's floor. Excess is not the way to go. Thin CA is not a gap filler. When the piano is unstrung, with the tuning pins removed, epoxy can be used to 1) reinforce the pinholes (as Bill advocated) or 2) fill the holes completely, to be redrilled. In the latter process, thin epoxy soaks through the rest of the pinblock, stabilizing it. While the "proper" procedure would be to replace the pinblock, several technicians (Rob Stuart Vail, for one) have had success with this procedure. Some have advocated its use in restoring early instruments. I would be extremely leery of dripping thin epoxy into a fully strung piano (sheared tuning pins would be likely, in my opinion). Keep in mind that CA fumes are toxic, and CA is very bad on human skin. Epoxy is much less noxious. Good luck, Patrick Draine
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