At 12:24 PM 7/27/2006 -0500, you wrote:
There is a support structure within HG's, pieces rest on pieces which rest
on pieces which are supported by glue or mechanical supports or bearnings.
Most instruments settle with age, but most stabilize, and good design
takes this into account.
When a sudden change occurs in a complex machine, especially one that is
mechanical in nature, I start the search by looking carefully at the
overall structure of the machine - is everything still straight, are all
the heights and widths and lengths still what they should be, are there
any suspicious bows or sags that weren't there before?
HG's respond significantly to a change in a dimension equal to the
thickness of a piece of notebook paper. It doesn't take much of a sudden
change in structure to move things more than that.
I would suggest that if the environment you keep this instrument in is
relatively stable, and the instrument has a good history of playing
properly, that you have some sort of catastrophic failure in some part of
the structure, and even though the overall appearance might not show it,
and it might not be catastrophic for the instrument as a whole (it might
not cause the whole thing to fall apart or be bursting at the seams) you
should probably investigate to see if this is a one-time shift, a
progressive failure, or something more serious.
Just my $.02 worth
Chris Nogy
Chris-
You are obviously accustomed to troubleshooting something! I like your
comment, "Most instruments settle with age, but most stabilize, and good
design takes this into account." I understand what you're saying, of
course, but I had to smile, thinking about the ubiquitous paper shims,
winter and summer chiens, movable melody string nuts and tangents,
etc. Few musicians other than hurdy-gurdy players deal with such
variations in adjustment, and accept them as normal!
I do not own the hurdy-gurdy in question, and I have no control over its
environment. Your comments are well taken; however in this case I am
troubleshooting what I perceive to be a problem which occurs on a many of
the hurdy-gurdies I've heard, or possibly, according to some, *all*
hurdy-gurdies, so I'm generalizing beyond the possible "catastrophic
failure" of one particular instrument. Perhaps this pitch-dropping effect
is in fact an unavoidable result of the nature of the mechanical system,
and as such there is no "fixing" it. Nevertheless, it is more apparent on
some hurdy-gurdies than others, and it would be nice to gain an
understanding of the cause and determine whether there is a repeatable way
to minimize the effect in new construction and/or existing
hurdy-gurdies. In other words, "good design taking it into account."
~ Matt
