>>However the pin can rise out of the bridge, due to hydraulics. As moisture >>is absorbed by the bridge, force is applied to the bottom of the pin, >>moving it upward. > > > This would seem to argue against bottoming the pin in the hole. Some > rebuilders (maybe some builders too, I don't know) drill the holes deep and > don't drive the pins to the bottom of the hole. Do you think this would > prevent this? I drill deeper just to not have to file the tops of the pins, but yes. That's another good reason. It's an even better reason not to drive pins to seat strings, because the pins will be pushed right back up where they were in the next dry cycle. Even with the hole deeper than the pin, the bridge will still push the strings up and down the pin with humidity cycles. The point of zero relative movement between the pin and the bridge tends to be somewhere toward the bottom of the cap. Perhaps the glue line has something to do with it. I have more tests planned, with epoxied in pins, and some with my latest capping material. I want to see what it takes to eliminate this curse in rebuilding or manufacture. Yea, I know Del, bridge agraffes. > Would tapping the strings down without tapping the pins down not accomplish > the same thing? > > Phil Ford It would, with fewer complications.
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