Jar of Water in Piano--Truth or myth?

[David Patterson]

Hello to all,

Maybe Dampp-Chaser enthusiasts are a bit cavalier about 'jars of water'
being ineffective; in most cases we havn't really done the research. But
it's associated in my mind with a large light bulb burn mark I have seen on
an upright soundboard. Thus a 'what about a container of water?' client
might be gently told that it's an idea from the 50's. And I accurately
convey that for every [1] I have seen with liquid in, there are [99] empty
ones rattling around down there.

But to address this issue of cracking and kiln-drying: I was taught that
cracks occur because of crushed wood fibres eventually contracting, a result
of the cycle of swelling/ shrinking/ swelling/ shrinking. This is indeed a
"killer to older pianos", if we accept the natural consumer notion that a
crack is way worse than a compression ridge. But is it? I really don't know.
Maybe they're about the same.

Is the following correct? -- I have accepted the idea that the precise
control of kiln-drying allowed for lower moisture contents in the boards,
thus eliminating cracking but practically guaranteeing some ridges over the
years. Also: doesn't sealing simply slow down the swings in EMC [as opposed
to protecting the wood]?

Post-1960's pianos seem just as susceptible to wild pitch changes as
pre-1960's pianos. Since pitch measurement is a good gauge of wear and tear
on the wood, I can't see how it follows that these school pianos "do not
seem to be so adversely affected by the drying out process of central
heating". The swelling, along with the low RH levels from heating, causes
the cracks; light bulbs and jars of water might have helped a little -- but
seem outdated now.

We all prefer to look at wood without a crack. But we really don't know how
the newer pianos will do in years 40 through 100.

David Patterson, RPT
Patterson and Company
Exclusive Dampp-Chaser Piano Life Saver Specialists for 15 Years

> -----Original Message-----
> From: Michael Gamble [mailto:michael@gambles.fsnet.co.uk]
> Sent: Saturday, March 19, 2005 10:48 AM
> To: Mike Kurta
> Cc: pianotech@ptg.org
> Subject: Re: Jar of Water in Piano--Truth or myth?
>
>
> Hello Mike Kurta & List
> It may be our weather in the UK, but many people have installed central
> heating in ther homes and central heating is a killer to the
> older pianos.
> By older, I mean pre-1960s. After that date kiln dried woods were used in
> piano construction, which, after shaping/planing, whatever, was
> then sealed.
> Take Knight pianos and Danemann pianos which in this country were made in
> vast quantities and sold, principally, to schools. Those pianos
> do not seem
> to be so adversely affected by the drying out process of central
> heating. I
> have many times instructed a client with an older upright to get
> as LARGE a
> surface area container as possible to fit on the bottom board of
> the piano,
> fill with water, mark where the water comes up to and monitor its
> evaporation. If they notice the water going down they know that were that
> container not there the moisture would have been extracted from their
> piano...!!! This is motivation  in taking care of their piano -
> which can't
> be a bad idea. I usually instruct them to get one of those sturdy plastic
> containers from a delicatessen or a used large ice-cream tub. No need for
> any wicking, the large surface area takes care of itself. The results on
> many older pianos can be quite remarkable. Pin blocks tighten up, tuning
> becomes more stable etc. So don't knock the use of water in this type of
> scenario - it works. It really does. At least it does in the UK.
> Maybe our
> water is stronger?
> Regards from a sunny spring day in the Downland Village
> Michael G.(UK)
> ----- Original Message -----
> From: "Mike Kurta" <mkurta@adelphia.net>
> To: "Pianotech" <pianotech@ptg.org>
> Sent: Saturday, March 19, 2005 12:06 PM
> Subject: Re: Jar of Water in Piano--Truth or myth?
>
>
> >    I also have seen many empty Mason jars in the bottom of vertical
> > pianos.
> > Its my feeling that the surface area of the water exposed to the air is
> > too
> > small to have any real benefit, and without some method of infusing the
> > moisture into the air (fan, heat, whatever) is does little good.  Then,
> > the
> > adage "out of sight, out of mind" takes over, the owner forgets to fill
> > the
> > jar, and its ineffective anyway.
> >    Mike Kurta
> >    Auburn, NY  Home of the Wegman piano
> >
> >
>
>
>