Good evening and compliments on the forum, I have just joined and I have two questions to ask in the hope that the problem can be resolved. It is a well-maintained Sholze piano from the 80s where when I press the Ab key piano or pianissimo, the pusher under the knuckle has friction and reaches the end of its stroke, stopping on the felt that holds it, whereas for the other keys the pusher remains a bit back; the sound comes out weak with little dynamics. I should preface that moving it with just a finger, the pusher moves very well without friction.
Last problem: the E3 has too much dynamics, and the sound results in being slightly metallic.
Attached are some photos
Thank you in advance in the hope of resolving this through regulation!
I understand that it is an upright? In any case, whether upright or grand, there are two observations: the friction or the lack of docility felt in the keys depends on the pins (in this case, from the escapement lever pin or the hammer pin). Perhaps you feel it more on this key because the phenomenon of excessive friction is at its limit... perhaps the process is advanced on many others as well, meaning the pins do not have the correct coefficient of smoothness, while still maintaining rotational firmness (anyway, I understand that you have checked such friction...). Second: it is necessary to check the correct key dip in relation to the hammer-string distance. An incorrect ratio causes the lever not to perform the escapement phase correctly. All this can certainly lead to a reduction in dynamics. In short, the mechanics must be checked as a whole and if it is just a matter of regulation, the piano will play well again. A good technician must know how to solve the problem. Exclude any lubricant!!!! ...except for a little graphite rubbed from a walnut shell or the roller (of the upright or the grand). One last thing: the black keys must have a correct dip ratio relative to the white keys and must be uniformly elevated relative to them by 12-12.5 mm.
What you are observing is the aftertouch, which is that small free distance the key must have once escapement has occurred. This distance of about 1.00 - 1.2 - 1.5 mm (on the key) should be almost equal, if not identical, on both white and black keys. There is a technical way to measure it precisely.
I don't see any photos. You can post them here for our members, but you can also send them to me on WhatsApp at no. 3393395980 (lately I haven't been able to open them on the forum...)
Let me know
Paolo Ferrarelli
P.S. Also refer to my video tutorials which illustrate the regulation
