"Puzzlers"

[Richard Brekne]

Farrell wrote:

> See how good these puzzlers are - even the originator may have something to learn here! Richard, tell me more about a damper stop rail on an upright. That would be the felt - covered rear side of the hammer spring rail - right?

I'm not used to those hammer spring rail pianos. But on pianos here there is a seperate rail for that this, tho it is most often regulated in the same fashion you site. Tho I have seen rails with adjust screws. . Either way For the whole thing to work right, the dampers have to be regulated correctly to begin with. That being said if when the key is fully depressed, and thereby damper fully engaged, any room between the damper wire and stop rail is what we are talking about here. Too much of this room can be a cause of your problem. And the tendency for the
bobbling  would be greater the lighter the tension is on the damper spring.... correcto ??

> That's not easily adjustable - although, I guess you can put shims between the action brackets and the rail to move it a bit. On an upright, I should think that the damper springs are tight enough that the damper lever would never loose contact with the wippen spoon, thus making the damper stop rail inconsequential. Is that not true?

Nope... not true. Thats why the rail is there to begin with. To keep the damper from flying back on medium to hard play. If you have really heavy damper spring tension, you might beable to nearly eliminate this... but then you would have other problems. What you want, is just enough spring tension on the dampers for them to do their job, and the distance between the stop rail and damper wires at a minumum with dampers fully engaged. That way the dampers movement backwards will be cushioned quickly on hard play, and contact with the spoon will be restored
likewise quickly. The idea is to feel as little as possible of this kind of "damper aftertouch" if you get my meaning.

>
> Terry Farrell
>

--
Richard Brekne
RPT, N.P.T.F.
UiB, Bergen, Norway
mailto:rbrekne@broadpark.no
http://home.broadpark.no/~rbrekne/ricmain.html