Warped Action Parts

[jolly roger]

Hi Terry,
             First you need to saw kerf the frame top and bottom,  about
half way through the frame. Alternately about 6" apart. Glue veneer into
the saw kerfs on the side that will effect the bending in the right
direction.  Leave the other side kerfs open to allow for expansion. Once
straight and fitted to the bed. Mount the stack, end brackets only secured,
you can now shim the feet of the other brackets.  Quite often just a few
kerfs at the top of the bow will do the trick, the weight of the keys will
help straighten things out.
You need to have the glide bolts jacked up and clear of the bed, to bed the
front and rear rails. Once you have these two rails very close.  Go ahead
and start bedding in the normal manner. 
Hope this helps.
Roger





At 05:21 PM 6/26/01 -0400, you wrote:
>Does anyone have any good tried-and-true methods (or any good guesses) for
>aligning/leveling a keybed, keyframe and stack? I'm trying to do a
>regulation on the Knabe I replaced the keybed in. Keybed is dead flat. I
>have put excellent straight-edges every which way on it and it is very, very
>flat. My trouble arose when I leveled the keys on a very flat bench with the
>action clamped down (back action frame rail bows up). Put stack on after
>leveling, put in piano, and keys were way low in middle. Turns out not only
>is the keyframe warped up, but the hammer and wippen rails are warped
>upwards in the middle also. So when you attach the stack to the keyframe, it
>pulls up the middle of the keyframe even more.
>
>We are talking about a good (well, depending on how you look at it) 0.060
>inch gap between a flattened back action frame rail and the center action
>frame foot (front and rear) - lesser on others and zero at ends. Obviously I
>can just shim under the feet, but even here I get some conflicting
>measurement results. I have even stood everything on end when measuring
>warpage to eliminate the straightening effect of gravity, but then when I
>lay it out on the flat bench, I get different measurments - not just a bit
>less or more, but rather the lowest foot is now the highest foot.
>
>Is there any hope here. I know very well what the heck the piano needs: a
>new piano, or at least a new action frame, keys, and top action (would at
>least solve this problem). But the plumber/electrician that is in full
>charge of the fate of this hospital-owned piano does not feel it real wise
>to spend much money on it. I'm just trying to get the %&*# termite-eaten
>thing to play!
>
>Thanks for any input. Anyone got a shoulder to cry on?
>
>Terry Farrell
>