We were introduced to Ballistol (weapons oil) in Germany as an excellent cleaner and lubricant for metal parts, developed for use on guns. But we were cautioned NEVER to use it on cloth or leather in piano work. The oil will collect dust and dirt, cause gummy friction and then is impossible to clean out of those materials.
When we worked with Kluge, Mr. Narath (from the founder's family and owner of the company at the time) told us that some piano builders and manufacturers specified the smooth side of the leather bushings toward the pin and others asked for the rough side. We always used the rough side toward the pins on both the front rail and the balance rail. That seemed to be the closest to using cloth and was able to be manipulated like cloth. In our experience, leather lasts a really long time - like 100 years - with no adjustments necessary. (No we are not that old, just have had experience with grands with leather bushings that have been in the keys for over 100 years).
If there is too much friction we, like Ryan, make sure the pins are very clean and ensure that the front rail pins are not twisted in any way. The leather can be eased with the normal easing pliers especially if the rough side is toward the pins. If the leather gets hard and starts to make a noise, the leather can be needled or even roughed up with sandpaper then eased as necessary. The only "lubricant" recommended by our knowledgeable friends in Germany is very fine talcum powder dabbed or rubbed into the leather.
A few of our supply houses have leather bushing strips in various sizes; check it out if you are thinking of rebushing a whole keyboard. There are tricks to installing leather bushings. As an aside, we were working with Ryan some years ago to give a class specifically on leather bushings which would have included all of the points in this discussion when the Executive Committee at the time or some sub-group of them quite rudely dis-invited us from teaching. Ancient history I guess.
If this has been of some help to some people, I am glad.
Joel
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Joel Rappaport
Rappaport's Piano Workshop
Round Rock TX
512-255-0440
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