Learning piano technology is a lot like learning to drive: you learn the basics, then every time you get behind the wheel, for the first year or so, you encounter stuff your driver's ed teacher never told you.
Most of my training has been through videos, which I would watch and then go over to my own Yamaha upright and try to figure out what in my piano matched what in the video.
I've seen several videos explaining how to bend the shaft that holds the damper in place. It is always emphasized that you have to make TWO bends, one to shift the shaft and the other to shift it back.
I always assumed this meant something important, but my Yamaha upright has damper SHAFTS that are STRAIGHT up and down.
Since this is the only piano I have taken apart over and over again, I had no experience of the system that uses bent wires for angling the dampers.
It's a little like learning to drive on an automatic, then suddenly your friend lends you his car but it turns out to be a shift!
How does my Yamaha manage to angle the dampers so that the bass dampers are angled to the left, and the mid range to the right?
The dampers are actually GLUED on at an angle to a dowl-and-screw mechanism that itself plumb on the damper wire, with each actual damper glued at an angle to match the slope of the strings--sharply to the left for the bass notes, less sharply to the right for notes after the first strut, those dampers gradually straightening out until by the second strut the strings themselves are short enough that they do not have to be angled at all.
Now, this is a great way to set things up, but replacing an entire damper means calculating (or visually measuring) the exact angle of the damper to the block. Then you have to actually glue it with old fashioned water soluble glue and try to keep the whole assemblage clamped in exactly that position until the glue dries.
Gluing the dowel part of the damper block while it is still in the piano and then pressing it very hard against damper assembly, which you have already placed touching the string(s) does not work for a number of reasons, not the lest of which is that the pressure needed to hold the it in place would damage the string or the damper wire or the sanity of the piano technician.
I still do not have functioning dampers for three or four mid range notes.
Advice?
Hank Mooney
San Francisco
granjon@sonic.net(email advice if any... I never actually answer my phone)
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Hank Mooney
San Francisco CA
415-640-2731
[Hank]
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