Slippery keys, center rail studs, etc.

Anton Kuerti 76063.737@CompuServe.COM
Sat, 08 Jun 1996 11:49:42 -0400 (EDT)

Dear Friends,

After being away on tour for most of the last two months, I have resubscribed,
but will unsubscribe again in two weeks when I go off for the summer.

First a comment, which I hope will not be taken amiss coming from something of
an outsider.  I think to preserve the value of the pianotech group - and I can
see  it is of very great value  -  people should restrain themselves and not
overburden the volume of communications.  Replies which are very specific and
not of interest to the whole group should be sent to the individual who made the
query, not to the entire list.  And if the answer is of general interest, maybe
before sending it out, check to see if it has not already been well answered by
someone else.  And perhaps no-one should post more than one message in a single
day, unless there is something really urgent that comes up.  I say all this
because even when I am at home, it becomes really time consuming to wade through
such a volume of material.  And to repeat (contrary to the principles just
stated!) I think that it is unnecessary to repeat the question in the answer.
In some cases the same paragraph has been transmitted 4 or 5 times.  Perhaps
overly long postings like this one should also be banned???

Next a question: what is the propriety of "advertising" things to the list?  I
have an instrument that is potentially for sale; is it a proper use of the list
to post the details?  Are you not afraid that like most other media the valuable
content will be overwhelmed by advertising?  Should rare and unusual items (in
my case, a concert grand) and trade tools etc. be allowed, and others not?

I had an experience at a recent Montreal concert that may be of interest to you.
A very dedicated technician met me at the hall at 11 PM (the only time available
in a busy hall) to help prepare for my recital the next afternoon.  There was a
lot to be done, and we worked together until 3 AM!!  (Fear not, I do not demand
or expect such extraordinary devotion, but the person in question graciously
offered it...)  I am a "night owl", but with a concert the next afternoon, I
decided to leave at 3 AM but he stayed another hour to finish a few things.

When I came back in the morning, I found the keys were terribly slippery.  Not
all pianists may feel the same way, but I like clean, smooth keys, but enough of
a coefficient of friction that when you press firmly, the finger will stay put.
To get the idea, you might put a finger firmly on a key and try vibrating from
side to side like a violinist; I want to be able to maintain the location, not
slide back and forth on the key.

I found I had real trouble playing accurately, and couldn't imagine why I had
not noticed this the previous night, and wondered whether it was my imagination,
or perhaps something I had gotten on my fingers.  When the technician showed up
again, I asked  and found out that after I left he had cleaned the keys with
Windex!  Obviously not a good idea.  So we washed the keys carefully; it didn't
help.  We sanded them lightly; didn't help.  I was ready to consider using one
of the other pianos in the hall, when he came up with another idea, which seemed
pretty ridiculous to me, but it worked really well and saved the day: he sprayed
hairspray on the keys!  It actually needed two applications, after which they
felt fine, not sticky at all but just enough friction to keep a stable sense of

Returning to a subject I brought up previously, I keep finding pianos where the
sharps go too deep; even if they don't "bury" they are too close for comfort.
At one top piano company, with outstandingly well maintained pianos, about two
thirds of their instruments were wrong in this respect.  A quick fix in this
case is to screw the center rail studs on which the action glides up; usually
about 3/4 of a turn is enough, unless the keys are really burying quite deeply.
If you are sceptical about this, put a touch block on a key and feel the
adjoining key as you screw one of the center rail studs up an down.  This can of
course only be done if they protrude sufficiently from the bottom of the action
that they will still be in contact with the key bed, and if there is a fair bit
of aftertouch and touch depth, because as you lower the center rail you will
reduce both of these.  You also have to check that afterwards the action does
not knock against the keybed in places, though I have found that if you do the
exact same number of turns at each stud and it was not knocking before it
usually remains OK.

I have heard that this ought never to be done, because it can warp the action
frame.  I question whether this is true; after all, when fitting the action to
the keybed, these studs have to be adjusted anyway, and a half or fuall tunr
would not be unusual; and you want a fair bit of pressure on the key bed just to
prevent knocking.  I would beinterested in reading some comments on this.

Anton Kuerti URPT (unregistered piano technician!)

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