I have a 1964 Steinway 100 vertical piano under my care that is now experiencing jack return failure on one note in the bass section. The wippen and jack flanges are at appropriate levels of friction, and I've taken some measures to ensure that the key is not binding on the rail pins.
Normally, on a small vertical piano of this age, I can write it off to cost cutting measures in the factory -- failure to back-lead the keys, when such would actually be very appropriate. But in this case, the design is clearly very intentional -- the keys are actually leaded forward of the balance rail. Only one note is actually failing, though others around in have jacks that return less than fully. A bit of downward pressure on the backs of the keys yields an audible snap as the jacks greet the hammer butt felt.
Adjusting the capstan does not help. I didn't run out to the car to grab my McLube and my key bushing iron, but I did heat up the end of a screwdriver with a pocket lighter and iron the front key bushing, such that nothing obvious in terms of excess friction appeared there.
Weighting the front of the key in a piano such is this is counterintuitive for me, but the thing obviously worked for its first 58 years. I'm reluctant to start removing lead, when evidently some thought and care went into placing it there in the first place. Maybe properly ironing and lubricating the key bushings revisiting balance hole fit will make the difference, but it is not obvious to me that that is the case.
Suggestions?
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Floyd Gadd RPT
Regina SK
(306) 502-9103
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