No Power Yamaha Revisited

[PatchWick@aol.com]

---------------------- multipart/alternative attachment
In a message dated 5/23/2003 7:25:04 AM Eastern Daylight Time,=20
davner@kaosol.net writes:

> We=E2=80=99re not =E2=80=9Cdetermining proper balance rail height=E2=80=
=9D, we=E2=80=99re first, bedding=20
> the keyframe =E2=80=93 and, yes, in some pianos the glide studs barely tou=
ch, but the=20
> point is to eliminate any knocking of the balance rail against the keybed=20
> when you tap on it.  If the rail =E2=80=9Cfloats=E2=80=9D at all, then the=
 keys don=E2=80=99t have a=20
> solid fulcrum. =20
>=20
> Depending on flatness of keybed, accuracy of keyframe joinery, stiffness o=
f=20
> the slats that connect the three keyframe rails, and any distortion the=20
> tightening of the stack down onto the keyframe causes, the balance rail wi=
ll sit=20
> at different heights above the keybed in different pianos.=20
>=20
>  Second, we=E2=80=99re setting an optimum key height, then leveling keys a=
nd setting=20
> key dip.  This is done with punchings and assumes the balance rail is=20
> already bedded.  I know you know this, but....
>=20
>    At the Little Red Schoolhouse (Yamaha=E2=80=99s technician seminar in=20
> California), LaRoy Edwards likened the keyframe to a bridge:  with the key=
s (the load)=20
> out but the stack screwed on, the front rail and back rail are bedded firs=
t=20
> (the two abutments at either end of the bridge), then the balance rail stu=
ds=20
> are turned down to just contact the keybed  (strip of newspaper pulled bet=
ween=20
> stud and keybed has just a slight drag), then the keys are put back in.  T=
here
> =E2=80=99s no spec. for =E2=80=9Cheight of balance rail=E2=80=9D, just for=
 key height, which is=20
> determined more by the keyslip and the fallboard.
>=20
>             The height of the balance rail is determined by bedding the=20
> keyframe and it ends up where it ends up.=20
>=20
>                 --David Nereson, RPT        =20
>=20
>=20

As I understand it, LaRoy's reasoning for bedding the frame without the keys=
=20
is that when there is no load (key weight) on the balance rail it will find=20
it's own "proper height" and then serve as an ideal and solid "foundation" f=
or=20
key height/level.

will

---------------------- multipart/alternative attachment
An HTML attachment was scrubbed...
URL: https://www.moypiano.com/ptg/pianotech.php/attachments/b2/36/c9/17/attachment.htm

---------------------- multipart/alternative attachment--