grand action problem

[Richard Brekne]

Dont  start shimming anything here... something is obviously amiss.  My 
first guess would go in the direction of wondering whether someone has 
replaced hammers and got the bore length wrong. My second guess would be 
to check whether or not the glide bolts are turned all the way up.  Then 
one could wonder whether the hammers have been so worn down that they 
simply cant reach the strings anymore... unusual... but it happens.

In anycase.... some more info as to the state of affairs with this 
action would be nice. What kind of shape its in. 7 mm is a very long 
ways away. Schimmel doesnt make junk....so somethings either been jerked 
around, broken, or just plain worn to bits.

If you first are in dire need of altering something... its fairly 
quickly done to sand off 2-3 mm from each let off button.


Cheers
RicB
Scott Helms wrote:

>Hello -
>
>I am regulating a 1984 6'9" Schimmel grand. It has a Renner action, and
>the letoff buttons are the wooden dowel type which screw directly into the
>underside of the hammer rail. My problem is that I can't get letoff close
>enough to the string. The closest I can get it is about 7 mm, and that's
>if the dowel is screwed all the way up against the bottom of the hammer
>rail. I've checked and double-checked all of my string height
>measurements, and it just won't work. I've only regulated about 10 or 15
>actions, so I'm still learning, but the only way I can see to get the
>buttons up higher would be to shim the entire hammer rail so it sits
>higher than the action brackets would indicate it should. There's plenty
>of room under the pinblock to take it as high as I need to, but I'm not
>sure that this is the proper fix for the problem. I'm afraid a change in
>hammer flange height might create checking problems or other regulation
>issues. I probably would only need to raise the rail a few millimeters to
>get the letoff I need, but why would this piano have come out of the
>factory with such a huge geometry problem? Am I missing something? Is this
>one of those "action spread problems" that I've heard about in Technical
>Institute classes?
>  
>