Key and damper Leads

[Horace Greeley]

Elian,

>In a message dated 97-05-28 03:26:42 EDT, you write:
>
><< I am working in a tropical country. Almost all the pianos here developed
> problems with the damper and key leads somewhere between 20 and 30 years.
> The leads start swelling and if not changed immediatley they=A5ll break th=
e
> wood around them. I was told it was a tropical condition, but I would like
> to hear more about it.
>  >>
>

Then Allan said:

>I have only run into this problem a couple of times and it seems to be a ca=
se
>of lead oxidation.  ...The only cure that I have found so far is to remove
>and
>replace te entire set of leads.  You've got my interest up now and I'll
>try to do
>a little research into the cause.  Maybe someone else on the list has alrea=
dy
>learned something about this and will reply.
>

Well, modesty does not prevent me from passing along the following:

Some years ago, various makers sold pianos as being "tropicalized".  While
that meant different things to different makers, in essence, the better
brands did things like - applying (read relative "soaking")  a thin lacquer
solution to various parts (like keysticks, keyframes, sometimes action
parts), leaving longer ends on key (and other) bushings so that those loose
ends could then be tacked down with bridle tape tacks, hammers lightly
"juiced" throughout.  The methods varied some, but I've seen this basic
kind of treatment done on a good many instruments while working in Mexico.

The cure, to the extent that there is one for already damaged instruments,
would probably include some pretty time-consuming work - dismantling the
action and back action, drying the various parts out, repairing/replacing
split out parts, installing new leads etc.  While there is not much one can
do for the old leads (besides throwing them away), I think I would apply a
10:1 thinner:lacquer solution to the affected parts (taking care to get the
insides of the holes for the leads), install the new leads, and then put
some more lacquer solution on the leads themselves.

Perhaps one alternative would be to use some material other than lead for
the weights.  There are different kinds of steel (Core-Ten) for example,
which only ever develop a certain thickness of the rust layer, and then are
sealed from further corrosion.  Stainless is usually too light altogether,
also harder to work.  Brass would be a better alternative, as it is easier
to work, and the corrosion on brass can be _somewhat_ contained.  Lots and
lots of shop time, in a well equipped shop, in any event.

In essence, what this boils down to is to leave no surface unsealed,
however you choose to do it.

You might have some problems getting any kind of reasonably decent lacquer
there.  Local substitutes won't work well.  You might want to get in
contact with Ben Truehaft to see what sources he has outside the U.S..

Hope this helps at least a little.

Best.

Horace







Horace Greeley			hgreeley@leland.stanford.edu

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