[CAUT] S & S D rest cushions

[Mark Dierauf]

Fred - I had the same experience. The action seemed fine until the 
client started working on the Chopin waltz Op. 18, with all those 
repeated notes. Furthermore, it only started happening after the hammers 
had been reshaped, which required raising the shanks up off the 
cushions. At the time I tired pinning the levers stronger, to no avail. 
In hindsight, I suspect the the plated may have been set a bit high in 
this piano.

I've also heard that the rep lever travel limiters that used to appear 
on some whips (those little metal 'L' shaped pieces back near the 
regulating buttons) may have been there specifically to prevent CAF, 
although I've never tested the veracity of this.

- Mark

Fred Sturm wrote:
>     I'm not surprised you can't reproduce it on a model. It seems to 
> take a rare set of circumstances for it to happen. When I first ran 
> into it, a pianist left a note after rehearsal, saying notes X, Y and 
> Z were having repetition problems sometimes. I checked them, found 
> nothing amiss, did the usual odd bits of things to optimize repetition 
> (regulation, spring tension). Dress rehearsal, and the pianist called: 
> "I'm still having repetition problems with those notes, and it is in 
> very obvious places" (can easily be heard by the audience). So I went 
> into the hall and had her show me. Yep, no question there were 
> problems. After watching and listening to what she did, I was able to 
> make it happen. I'm not sure I could do it again at this point, but I 
> could do it consistently at the time. It had to do with precise timing 
> of a second blow on the key, as well as the precise way the first blow 
> was executed (pretty hard and staccato). What seemed the easiest 
> solution was tacking a bit of felt onto those cushions. Presto! 
> Problem solved. (All shanks were a good cm or more above the cushions).
>     Since then I have heard a number of fellow techs describe the same 
> thing. Within the past 3 - 5 years, at a NYC Steinway Academy session, 
> Eric Schandall mentioned that you needed to be sure the shanks were 
> close to the cushions, as otherwise a certain kind of action lock up 
> could happen. Sounded like exactly the same thing.
>     So, be my guest, believe it or don't believe it. You may or may 
> not ever run into the problem. But it is not just my own personal 
> imagination. It is a hallucination shared by others. And anyway, it's 
> a good idea to have that distance close for other reasons, partly as 
> described in my last post and by David Love.
> Regards,
> Fred Sturm
> University of New Mexico
> fssturm at unm.edu