[pianotech] S&S vert. sost.

[Robert Anderson]

Last week I tuned a S&S '45' #544790. I didn't measure the ht., so I  
don't know if the model is 4510 or 1098. They both have the same  
action as far as I know,
There were two leaking dampers - A#2 and F#4. The sost. knife edge was  
just barely holding them away from strings. I pulled the action to  
look at the tabs. The A#2 tab was 0.5 mm lower than its neighbors. I  
would have preferred it to be level with the rest, but I couldn't see  
how to do that. If I were in the shop, I could put the lever in a vice  
and clamp the sost. wire with a vise grips and try to tap it further  
in or, that failing, extract the wire, cut off some excess and tap it  
back in to the proper length. I would like to think that the sost.  
could be properly adjusted without going to that length. Am I wrong?

I managed to adjust the knife edge so it didn't interfere with those  
two dampers, but in the process I made the overall function of the  
sost. a little worse. I ran out of time, and I will still have to  
return to deal with it. I am concerned that the sost. tabs are not  
even in the fore/aft direction when the action is in the piano  
although I observed that the dampers looked to my eye like they lifted  
evenly with the pedal. I can't see why else the knife edge lifts some  
of them but not all of them.

I think I need make a finer adjustment of damper lift from the pedal.  
Does that sound right? Does anyone have a methodical way of regulating  
this sost. that might help me? One thing I like about it in contrast  
to the grand system is that the knife edge can be raised up and down  
by loosening the hanger bracket screws and sliding the brackets rather  
than having to bend them as in the grand. On the other hand, I found  
it difficult to gauge how much I was moving the knife edge either up/ 
down or fore/aft. I have had almost no experience regulating the S&S  
vert. sost., so I would appreciate any advice.

Thanks,

Bob Anderson
Tucson, AZ