Im working on this Yamaha C108 it had several broken bass strings (is curious, another Yamaha M404 had almost the same broken bass strings. They both had the same frame and string length, it was easer to make the bass strings cause were identical. how that can be?
Any way, while looking it the C108 I notice that the middle tenor section from F4 to F6 had been replaced before, I notice it because the replacement was made so bad, the pin wasn't turn out to install the new string the new coils are touching and compressing the wooden bushing, I try to figure out why this person did that and i notice that the scale on the piano has something wrong.
I decide to measure all the strings and i notice that the scale written on the bridge is different from the one it has. The wire numbers on the bridge start on 18, but the strings at 17.5 and so on, all wire sizes are half thiner of what it said on the bridge, but the ones that have been replaced follow the bridge guide, so it has a double section of 16 and double section of 15 is a mess.
Other than the ones replaced, are factory installed so what went wrong at the factory the guide stamp on the bridge or the wire installed.
The best probably is to take out the replaced wire and continue with the factory scale ignoring the bridge guide, just following the logic of the scale, the points of where the size change are the same.
Or have the piano re-scale and restring it all off course keeping the bass strings
Since the M404 seems the same, I´ll look at the scale to see if is different or has the same issue, the bridge guide has the same wire numbers and it change at the same points but i didn't measure the strings
Thanks a lot
Sergio L. Ruiz Jones
Pianos & Pianos
Afinacion y restauracion de pianoswww.pianosandpianos.com