There is nothing to be done! Whoever intervened has "killed" the hammers. One must intervene with gradualness and parsimony in certain areas of the hammers. Based on what you are describing, I don't think it's possible to recover a good hammer tone! I recommend shaving them! I advise replacing the hammer rail (including the capstans) with the same specifications as the original WITHOUT ABSOLUTELY throwing away the original and leaving it mounted on its capstans!!!!
There is nothing to be done! Whoever intervened "killed" the hammer. One must intervene with gradualness and parsimony in certain areas of the hammers. Based on what you describe, I don't think it's possible to recover a good tone from the hammers! I recommend shaving them! I advise replacing the hammer rail (including the capstans) with the same specifications as the original one WITHOUT ABSOLUTELY throwing away the original and leaving it mounted on its capstans!!!!
Thank you, Maestro. I have one last question.
Since you mentioned recalculating the striking point, and since I am not sure that whoever installed the current hammer rail (it is not the original one, unfortunately) respected the striking point, I was wondering what fraction I could calculate on the length of the string to find it? Is there a general rule of thumb? (my doubt is solely for the central area; I imagine I would measure the length of the string from its exit from the agraffe, down to the tip of the bridge...)
Hello everyone, hoping I am not in the wrong section, I am taking advantage of this discussion on hammer geometry to ask for some information. For my Kawai KG2, the Japanese manufacturer sent me an original hammer set years ago which, however, differed in the tail because it was square, while the one installed was rounded (my deposit was returned to me). Now, opting for an Abel, whose measurements are absolutely identical to the original Kawai hammer set that I kept, I encounter the same difference in the tail (again square). The question is whether it is advisable to install a hammer set that differs from the original only in the shape of the tail? Thank you all. Kind regards.
Hello everyone, hoping I am not in the wrong section, I am taking advantage of this discussion on hammer geometry to ask for some information. For my Kawai KG2, the Japanese manufacturer sent me an original hammer set years ago that differed in the tail because it was square, while the one installed was rounded (my deposit was returned to me). Now, opting for an Abel set whose measurements are absolutely identical to the original Kawai hammer set that I kept, I encounter the same difference in the tail (again square). The question is whether it is advisable to install a hammer set that differs from the original only in the shape of the tail? Thank you all. Kind regards.
m
Hi Massimino, the pointed shape of the tail depends on whether you requested pointed tails when you ordered the hammers. In my case, I simply requested them "already shaped," and as a result, they sent me both rounded and pointed ones, perhaps because my piano's design allowed for both.
In my opinion, with slightly lighter tails, the piano sounds better... then it also depends on your preference. The key weight must then be rechecked; if overall the hammer weighs more or less than the originals, it should be adjusted, also because the type of wood used makes a difference in weight, not just the shaping and the shape of the shank.
In fact, the difference lies in the shaping of the tails to be performed with a specific tool, copying the radius of curvature. The hammer rail should weigh the same as the original, otherwise slightly modifying the keyboard dip. It is not that "with lighter tails the piano sounds better". The hammers must be of such weight and shape that, when glued, respecting the striking point and inclinations, they respect a downward weight and, above all, a return weight dictated by the Manufacturer's design. Only in this way will good repetition be ensured. Every small difference that alters, indeed, the geometry of the action can compromise its proper functioning. A correct regulation of the entire action is extremely important! The condition of the felt on the jack heels as well as the gaskets of the keyboard keybeds is also important.
Hi Musick, I haven't requested the hammers yet precisely because of this different tail shape. Abel provides a hammer mill that matches all the measurements of the original Kawai KG 2 except for the tail, which is square instead of tapered. My doubt is exactly this: whether to install hammers with a totally different tail, even if, from what I understand, the problem would then be in a new voicing/weighting. Thanks everyone
Hi Musick, I haven't requested the hammers yet precisely because of this different tail shape. Abel provides a hammer rail that matches all the measurements of the original Kawai KG 2, except for the tail which is square instead of tapered. My doubt is exactly this, that is, whether to install hammers with a totally different tail, even if, from what I understand, the problem would then be in a new voicing/weighting. Thanks everyone
As the Maestro rightly pointed out, it would be best to respect the manufacturer's choices, as they know better than anyone what should be inserted into the context they designed in order to ensure perfect functioning...
The shape of the hammer head is also important for the effectiveness of the hammer's own "parata" (strike) on the capstan! This "square" shape is nothing more than an unshaped hammer, left exactly like this to allow those assembling the hammer rail to shape the heads like the originals. The hammer supplier can, in fact, copy the shaping from a sample....but since the weight of the hammer rail always differs slightly from the original, the shaping of the heads can be, within certain limits, a means for the assembly technician to get closer to or even make identical the weight of the hammer and consequently the let-off and key return weights.
Thank you all. It seems to me that the hammers with square tails should not be mounted. kind regards
m
They must NEVER be left rough "at the back" but worked with a grinder.... because that is the "snagging" point of the parade, and if it were square it would not fulfill its function
Initially, I hadn't quite understood if (in case) you were referring to the taper of the hammer on the sides, which would be two additional cuts made with a table saw, when after "rounding" the hammer results in being even heavier than the original, and therefore must be further lightened. Does he show them to you here at 1:22?
And what about re-felting? Paolo, on one occasion you told me that it isn't done in modern grand pianos. But for what reason? Isn't it a way to preserve the originality of the instrument? I had it done on my Kawai upright and it is wonderful!!! Visually, the hammers are identical to when I bought the piano; as for the sound... marvelous!!!
Unshaped hammers... On my old piano, a hammer rail was installed without shaping the tails!! I cannot call someone incompetent just because they do work different from mine - at most I can be dissatisfied and change it - but I believe that in this case, I am more than justified!!!
It must be seen on a case-by-case basis. I do not doubt that the re-felting turned out well, but on a Kawai, it is appropriate to choose a hammer set for Kawai.
Generally, one resorts to this solution when faced with particular hammers, whose core is difficult to reproduce, e.g., if certain specific weights and masses must be respected, etc.. It must be seen on a case-by-case basis
