Soundboard Moisture Content

[Greg Newell]

Thank you Del ( and congrats). I appreciate your quick response.
I've been thinking of a purchase but what I understand you to say is that 
no meter will give a reading likely to be accurate enough to warrant the 
purchase. I was hoping to have something for shop use as well and also 
something to show a customer. The likely scenario is that I encounter this 
Petrof or similar piano/situation with the compression ridges and can then 
point to an unusually high reading on the meter suggesting that there are 
problems somewhere contributing to this phenomenon. Could you tell me how 
you address this kind of a situation?
I am in the rather sticky situation of having recommended this piano for 
purchase to this customer. They bought it second hand from another of my 
customers. It could be simply that the compression crowned board is doing 
what they all seem to do eventually. The timing stinks though since this 
happened within about 8 months of them making the purchase.

Best,
Greg




At 04:32 PM 3/30/2004, you wrote:
> > Can anyone give me an idea of the normal moisture content of a
> > soundboard?
>
>There is no "normal" moisture content for soundboards. It depends entirely
>on the temperature and humidity conditions immediately surrounding the
>piano. The MC changes along with the climate changes.
>
>
> >
> > The current conditions are Northeast Ohio older home but fairly well
> > insulated. The heating system adds moisture to the room via an April air
> > type unit in the forced hot air furnace. The piano is a roughly
> > 10 year old Petrof. The weather lately is normal spring type weather for
>this region
> > i.e. 35-55 ish degrees with off and on rain. The customer used a pin type
> > moisture meter on his own soundboard and reported a 21% reading.
> > Have any of you taken readings directly on the board with either
> > a pin type or a pin-less type meter ad compared them to the Hygrometer
> > reading some of us normally take? Would it be useful information to obtain
>these
> > readings?
> > If you were buying one for the main purpose of measuring boards would you
> > buy pin type or pin-less? Why?
> > Thanks in advance for your inut.
>
>
>Neither type of moisture meter is going to give very accurate readings on a
>finished soundboard as installed in a piano. Partly because the panel is so
>thin and partly because it is finished.
>
>It is unlikely that the soundboard in question has a MC anywhere close to
>21%. For a soundboard panel to reach a MC of 21%, assuming the temperature
>in this home is between 60ºF and 80ºF, the relative humidity would have to
>be something in excess of 90%. Unlikely, unless the house is equipped with
>steam generators. In other words, with the outside conditions you indicate
>it would be pretty difficult to achieve this.
>
>The best way to determine the MC of a soundboard is to monitor the
>temperature and relative humidity and determine the equilibrium moisture
>content by referencing a chart such as that found in The Wood Handbook. More
>likely the MC of this soundboard is in the 7% to 10% range.
>
>Del
>
>
>_______________________________________________
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Greg Newell
Greg's piano Forté
mailto:gnewell@ameritech.net