tight pinning

[Oleg Isaac]

Peter KESTENS wrote:
> 
> 't MUZIEKINSTRUMENTENATELIER
> PETER KESTENS
> BELGIUM
> KESTENS.P@DEBCOM.BE
> -----Oorspronkelijk bericht-----
> Van: Oleg Isaac <oleg_i@club-internet.fr>
> Aan: pianotech <pianotech@ptg.org>
> Datum: woensdag 19 november 1997 1:25
> Onderwerp: tight pinning
> 
> Isaac Oleg writes:
> 
> "This grand piano is in a very moisty place , something like 65%
> permanent moist, and the pinning is very tight.
> 
> Consider the piano will stay in this moisty place - is it correct to re
> pin, or is there a better solution ? (the soundboard seems ok, too much
> crown but it sounds 15 " of nice ringing on note #65)
> 
> I will appreciate an idea, something to help me for the regulation at
> first. In my place there is 50% moist env.
> If I dry the flanges, the pinning will free, but I will be papering a
> lot, and it surely will not stay squared and free when it will be back.
> 
> Is it a job for Damp-ChaserMan ?"
> 
> My question is: Whats about the ideal  % of moisture? Where I live
> (Blegium), for the moment I have about 53% of rel. moisture.  It can go to
> about 60-60% but also get down to 40-45% in winter.  Untill now I've never
> had that much problems with tunings of piano's.
> 
> My opininon is: it's much better to place the piano in a place with a high %
> of moisture than in a very dry place, because the wood will be no satisfied
> and causes cracks in the soundboard.  Is this a good way of thinking or am I
> toally wrong?  Any reactions would be greatfull accepted.
> 
> Peter

Peter, I agree with you.

Tech sepcifications I received from BOSENDORFER factory indicates that
the moist must be something AROUND 50% and the moist in the wood is then
9% for 20° c dry temperature AT THIS MOMENT, It changes with the rel
moist and temperature, growing dependently .-  STEYNWAY moist is 42% rel
at the factory (where the sounbords are made) - 
By the way, there is a 8° for 25 cm slant on the bridge, toward the pins
(is it TOWARD ?) as I asked.

I have a diagram showing the relation between rel moist of air,
temperature and wood moisture.
 At  20° c 50% rel moist, wood moisture is 9,5 %
 At 20° c 40% rel moist, wood moisture is 7.7 %
At 20 °c 60 % rel moist, wood moisture is 11,5 %

wood moisture wiil be less with lower temperature, and grow with the
temperature, (some 0.5% plus with 10 degrees more)

Hope it is readeable 

Our superior syndycate of dealers, in France, (SYCOMUS) produce a few
years ago a warranty for the piano (a document) indicating that the
piano MUST be in a place with 60° - 65 % moist (and if not the warranty
is off !) They are totally wron from my opinion. 

The big thing here, is to have a minimum of changes and they must be
slow.
You seems to have a "normal" moist in the air like we have in Paris.
I agree it is better to be in a moit place than a dry.
I don't have problemes with tuning pins, but pinning (flanges) is too
tightrel moist changes with temperature of air too.
Steel began to corrode at 67%

If I made mistakes please let me know

Cordialement
Isaac