Friction

[Newton Hunt]

There are three elements here.

1.    The pins need to be clean and polished.  Anything less than a high
polish will cause friction.  I like to use a German made metal polish call
"Flitz".  It is expensive but since very little is used at one time it lasts a
very long time.  I have tried many others but this is the best.  If not
available there use any other good polish.

2.    Balance pin holes must be made to fit the pin snug but not tight.  When
the action is assembled and if you lift a key at the front and let it drop it
should drift down gently to it's rest position.  If it stays in place it is
too tight and needs to be eased by enlarging the hole, very slightly.  I use a
Yamaha invented tool that is a long tapered cone that has been ground flat on
two sides so that it passes through the key button to the bottom of the key on
the inside.  It can be rotated and pushed down to ease the hole from the
inside.  If it drops fast it is too loose and may need to be made smaller with
steam or saliva.  If the key can be moved front to back more than one
millimeter than it may need a repair.

3.    If the pin is polished, the holes are eased but it is still not free you
will need to ease the buttons by squeezing the wood with a set of key easing
pliers.  Go easy here because it is easy to over ease unless the buttons are
hard wood in which you will need to squeeze harder, being careful not to over
ease.  The bushings should hold the key upright but allow it to move freely.
There should be .2 mm play if the button is moved left to right and back
gently.

The front pins and bushings should be treated in exactly the same manner
except there should be about .3 mm play left to right.

If the whole keyboard is problematic remove all the keys, polish the pins and
I like to use a lubricant of a teflon spray or a little Protek will work as
well.  Replace each key, one at a time, carefully easing each part and making
it perfect before going on to the next key.  This way when you are finished
you will have a perfectly functioning keyboard and if there are other friction
problems they will definitely be elsewhere.

Hope this helps.

                Newton
                nhunt@jagat.com

ROGERIO CUNHA wrote:

> To the list
> I am regulating a grand action where there are very much friction and I
> detected that the great of this friction is on the balance rail pins. What
> is the better product in order to lubricate this pins?
> There are another good thing to do?