Up & Down

[Kenneth W. Burton]

	John,

	Is it possible that you have been seeing the piano when the
humidity cycle is rather favorable? And, that if you checked the Relative
Humidity in January and August, you would find the conditions that cause
these huge pitch swings?
	In Calgary, an August reading in our church would be about 55% and
a January one would be about 15%. That'll do it!

	Ken Burton "Doctor Piano" Calgary Alberta

On Mon, 29 Sep 1997, Sy Zabrocki wrote:

> 
> To John--from Sy Zabrocki
> 
> This extreme up and down condition might be more prevalent in a church or school. In the winter months in Montana these buildings can get tinder dry when the furnace is on all winter. Every last bit of moisture is extracted from the piano. Then in the summer (especially this summer) the furnace is turned off and the spring humidty comes flooding in. The thirsty wood drinks in as much as it can. 
> 
> In a home there is some humidity from the bathroom, kitchen, laundry, plants and even people. The cubic area in the home is also smaller than the church or school. This summer's humidty has been extreme. I've been lowering pianos for weeks.
> 
> Sy Zabrocki
> ----------
> From: 	John R Fortiner[SMTP:pianoserv440@juno.com]
> Sent: 	Monday, September 29, 1997 8:48 AM
> To: 	pianotech@ptg.org
> Subject: 	Up & Down
> 
> List:  If you can give me some clues, hints, etc. regarding this
> situation I would really appreciate it.
> 	I have, over the past 3 years, been servicing a Bradford uprt. in
> a nearby church.  The first time I tuned it I had to lower pitch at A4
> 42c.  The lady that was in charge of the music for the church told me
> that the last person that tuned the piano had had to raise the pitch
> quite a bit and wondered if he had raised it too far.  At the time, I
> thought that was a possibility.  However, since then, I have had to raise
> the pitch 40c in the spring, then lower it in the fall, then raise it
> again in the spring, etc.  The pitch changes have been about equal each
> time within 3-4c.  I am stumped as the humidity has been between 30 and
> 45% each time that I have worked on it.  Yesterday, I tuned the piano
> again (fall tuning) to find that the instrument was 45c high  at A4 and
> closer to 80c high in the top octave(no wonder they said it sounded
> terrible with their other instruments.  The bass is staying rather stable
> (rises and falls a few cents), but the tenor and treble really stray from
> where they are supposed to be.  
> 	Before you ask, yes, I have tightened all available plate
> hardware that goes into the wood structure.  Tuning pins are nice and
> tight, but not overly so.  The piano is about 2 feet from a baseboard
> heater which has a shield to protect the back of the instrument from
> gross temp/ R.H. changes.
> 	The church's flooring is wooden over a basement that also has a
> piano in it.  The downstairs piano stays nice and stable (+/- 3-4c).  Is
> it possible that the flooring is shifting enough with weather changes to
> "tweak" the piano THAT far?
> 	Any and all input regarding this will greatly be appreciated.
>  
> 	Thanks in advance for any input that you can give in this matter.
> 
>                                                                      
> John Fortiner
>                                                                       
> e-mail: pianoserv440@juno.com
> 
> 
> 
>