Soundboardcrown

[Farrell]

Delwin D Fandrich wrote:
> 
> Even with this technique you should try to dry your soundboard panel down to
> approximately 6% to 7% moisture content. This will still require a special
> heated room, or box, but it can be quite simple. A plywood box large enough
> to hold your soundboard panel and with room for a small space heater will
> do.

My box measures 8 feet by 6 feet by 1 foot. I have 250 watts of DC heater bars on the bottom of it and a small fan (Radio Shack) to circulate air. This set up will easily warm the box 30 to 40 degrees F above room temp. Right now my box is warming some test wood pieces for calibration. My room is 60 degrees F and 41% RH. The box is 90 degrees F and 17% RH. According to the charts, this would produce an EMC of 3.8 or so percent. Obviously, plenty drying power for any of my needs. I have a reptile environment temperature controller that keeps the temp real steady at whatever temp I dial in.

> You can estimate the moisture content of the soundboard panel by
> monitering the temperature and relative humidity inside the box and
> comparing those to charts printed up for the purpose. The US Department of
> Agriculture has placed the entire book, "Wood Handbook: Wood as an
> Engineering Material" online. 

Is this how you determine the MC of your panels before rib glue-up?

If anyone wants a copy of Chapter 3 of "Wood Handbook: Wood as an Engineering Material" (it has the charts in it) I can email a copy to you. It is in PDF format.

Terry Farrell