Hammer Mass

Roger Jolly baldyam@sk.sympatico.ca
Sun Aug 24 18:40 MDT 1997


Hi Ed,  With regards to hammer mass re tone and touch there are several
observations that I have encountered over the last 5 or 6 years.
  1. With the rising cost of Walnut there has been a shift by the
manufacturers to use materials like Birch and Maple for hammer moldings
with the resulting increase in mass. All too often the touch weight has not
been corrected.
Therefore triming down the sides of the hammers can make a great
improvement to the touch of the instrument.
  2. I have wondered about the Korean pianos that I have encountered with
parallel moldings and down touch weights as high as 70gms if the maker is
just saving money by cutting out one operation. Removing mass from these
instruments has a great effect on touch weight and impact 'noise' . In the
treble section a noticeable reduction in V bar noise is also apparent, plus
a longer singing duration of the note.
  3. We have to be careful about the model and make of instrument that we
are talking about, Manufacturers with proven models and quality control
systems seem less of a problem in this area. The lower quality makers
invariably have other problems that that have to be corrected before
proceding with the half a days work involved with tapering a set of
installed hammers. However the results are well worth the labour when
accompanied by a good regulation and voicing. It can make a budget range
piano sound and feel very respectable.
  4. Pianos that I have treated in this manner have convinced me that
voicing stability is improved , possibly due to less compaction to the face
of the hammer, but this is gut feel and not a scientific observation.
  5. I can agree with the comment that we do not know the ideal dwell time
of the hammer on the string, and what is the ideal amount of whiplash in
the shank for the treble hammers??
  6. The lighter hammer should also reduce the amount of metal fatigue that
takes place every time the string is struck, therefore the instrument
should maintain its singing quality for a longer time.
  7. Question. will a high mass hammer increase V bar wear? 

  Finally the more I think about the original question, the more questions
come to light.
Roger Jolly
University of Saskatchewan
Dept. of Music.