[pianotech] Broken Grand dampers

[Bob Tate]

Hi people,

I've had to be away because of a bad back--still hurts like crazy.
_______________

I believe a major problem may have just happened with my Estonia 190.  

I've been working on getting the una corda pedal to be just as I want it, or rather make certain the hammers hit the strings in just the right place when it's depressed.   (i.e., not how depressed I feel right now)

Here's what happened: 

this morning, I made a minor change to a hammer flange position. I put the action back in the piano. 

When I pressed the una corda and let it return, the alignment looked as I wanted it, the damper barely missed the left string at full una corda.  The shift works properly.

Next, I pushed down the damper pedal. 

All the dampers lifted as expected, however, when the pedal was released, the entire set of dampers hung, just above their "at rest" position.

I checked the action to make certain it was properly seated on the key bed  and in the piano as far back as it could go. It is.

I tried the damper pedal again.

This time, on the damper return, I heard a "creeeek" or rather, "creekcraaack." And the dampers still hung slightly above their at rest position.

Not liking that "crack" sound; with the damper pedal not depressed,  I lifted and let drop, each damper head,  manually.

All worked as expected, except E2 (the last damper before the end of the bass bridge and before the bass/treble strut).
Lifting it, I felt a little, loose up/down and side to side, wobble.
Letting it drop, maked an audible "click," then, "thud" as it returned to where it started. 
The thud sounded like wood on wood.

I pulled the action. Looked at and wiggled the damper flanges and wires, checked for loose screws, and saw/felt nothing wrong.

With the action still out, I checked the sostenuto, which as had the dampers, been working perfectly.

The sostenuto is a complete mess: dampers lift haphazardly or not at all.  (The tabs all look in-line.)

Not having much grand damper repair experience, I returned the action and have stopped.

I've called for reinforcements. I'm afraid this may be a major problem: a broken damper rail flange or even rail itself, broken damper return spring?

Any ideas of what I might be able to check, without taking apart the damper mechanism (and probably making matters worse)?  
--I know of nothing more I can do or will do, lest you have a suggestion. 

what we know is:  
the dampers hang barely above the strings when "at rest," 
the manual lifting of E2 (last damper before the bass strut) makes an audible "click" and then, wood-on-wood "thud" when allowed to drop to its rest position, 
the sostenuto is a total mess,
the shift works okay.

I won't touch it, unless it's something easy to check; but, I'd like to have ideas as to what it might be.

Thanks,
Bob T

______________________________________________________________________
A painter paints his pictures on canvas. But musicians paint their pictures on silence.


      
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://ptg.org/pipermail/pianotech_ptg.org/attachments/20090122/91038437/attachment-0001.html>