Hi Mark Thanks for filling in the blanks here (below). I might add that the stuff constitutes a 3rd material with characteristics of its own. Along with what you've mention it adds up to something quite capable of affecting false beats in a way that has nothing to do with pin tightness. And John, actually it does add mass... not enough me thinks to get into that (yet another) area of question relating to false beats. I'd love to stay and play but I am off for a nice 2 week Easter Vacation. Aside from encouraging a few of you to actually buy a basics logic reasonings book and review its contents (actually quite fascinating stuff so you'll have fun) I'll leave this subject on the following points and let y'all hash it out as you wish. On the one hand you have the loose pins cause false beats theory. It is supported by two items... an observation and another theory. --- One observes that CA glue quite often quites a false beat in a presumed loose pin. --- One theorizes that the collar around the pin at the bridge can be loose enough to cause flag polling and that this is the basic mechanism. On the other hand you have several observations and a clear way of disproving the above theory as valid. --- One observes that CA will quite false beats in tight pins as well --- One observes that there is no statistical correlation between false beats and loose pins. --- One observes that tight pins are actually as likely to experience false beating as loose pins, which further undelines the lack of a statistical correlation. --- One observes that other methods of <<tightening pins>> yield roughly the same results. --- One observes that there are other factors seem to influence the presence of false beats. --- One can actually observe more... but this will suffice. --- Flag poling can be discounted by simply simulating the condition. Take your next shop junker and before tear down find 5 clean strings in the treble. Loosen them and then insert a number 28 or so center pin underneath the string on the bridge surface. That puts the string high enough on the bridge pin to give the flag poling theory all the chance in the world to show its face. I've done this a few times now so I know the results. Seems to me there is every reason to question whether or not loose pins are directly causal to false beating. Actually... seems to me there is even reason to question whether or not they are really in the picture at all. None of this changes the fact that CA has a good affect on the problem of course. So go for it. Cheers and Happy Easter RicB --------------------- Mark Schecter writes: 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. * Mark Schecter*
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