Brian Trout wrote: > Hi all, > > The discussion on the pros and cons of replacing loose bridge pins with the > next larger pin has been interesting. > > I have to wonder what is the method that you would use if you were to do > this? In a word, NO. Bridge pins are not like tuning pins. Loose ones cannot just be replace with the next size. First, the strings in each section are scaled to fit a specific pin size, (unless of course we are talking about a Winter spinet which never changes sizes). This is very important because of false beats. I have seen several pianos over the years where someone replaced pins with the next size. Tuning was a nightmare and the tone quality was decisively diminished. Second, using larger pins will inevitably cause the bridge to crack. Thus the repair becomes temporary. Larger pins are used in areas of the bridge where the pins/strings are farther apart. Smaller pins are in areas where the pins/strings are closer together. Installing larger pins will ultimately lead to the problem getting worse. Even if you pre-drill the holes, the stresses between the holes are closer and they are guaranteed to crack again. Remember: Bridge pins need to be as tight as they can possibly be in order to avoid even the slightest loss of vibrative energy. If you accomplish this with larger pins with less wood between them you are pushing the limits. Third, the pins must be spaced enough so that the strings will comfortably pass through the pins. In the pianos that I have seen that had this operation done, almost always there was barely enough room, if at all, for the strings to pass through the high treble without rubbing against the neighboring pin. Suffice it to say that this is not a very good repair. It sounds good and seems like it should work but there are many negatives against it. The only appropriate repairs are 1: Recap the bridge, (if the piano is worth it), or 2: remove the pins, epoxy the holes, re-drill them the original size, and install new pins followed by properly filing them to the correct height. Okay, maybe someone here will disagree with me, but you won't catch me doing it any other way in my shop. Rob Goodale, RPT Las Vegas, NV
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