private

[erwinspiano at aol.com]

? Hey Jim
?Seriously. wanna make me one?Too busy to gear up & besides you already conquered the learning curve. Some one could make money selling these contraptions. Could be you.
? Thanks
? Dale



Coming to this thread a bit late, with a couple comments and questions.

Gene, I went 'round robin hood's barn on this accurate, trustworthy mc readings 
question. You might check  
archives January '08 under "moisture meters?" for more of the discussion.
 
As a result of that thread, I ended up building a version of Ron's 
direct reading dial indicator gizmo...and I love it! 

A couple of points I learned as I worked this through:

1-Many of us were complaining about the inconsistent and generally weird results 
achieved by oven drying. That's because oven drying is defined as between 
215-217 deg f....a pretty narrow window. Before I calibrated Ron's gizmo,  I 
experimented with trying to get consistent results in the oven. The answer was 
to be fairly anal about the oven temp. 

My oven's thermostat is out to lunch, so, not having a lab oven, and being 
generally cheap, I calibrated the oven by:

-first taking a plumbers water testing thermometer's probe and placing it in 
boiling water, marking where boiling 212 was on the dial.
-then took a very small glass vial, like a dropper bottle, filled it with 
vegetable oil, put the plumbers thermometer in it and put it in the oven. When 
plumbers thermometer read just a hair over 212 in the oven   
marked the oven dial and waited for the temp to be stable. For me this got 
things close enough for jazz .

2- Hoadleys expansion/contraction/mc change formulas imply that wood's expansion 
rate is linear. Expansion rates are in fact not quite linear! That  means the 
meter is best calibrated and 
read at or reasonably near the mc you are shooting for. That's really not a 
problem, because we only really care when the board has achieved that target 
6.5% or whatever your shooting for.

3-Hey Jude, the gizmo saves having to invest in highly accurate hygrometers 
(yeah, right) for your hot box. I've been burned enough times by fancy expensive 
measurement devices to return to my pre-industrial roots...just stick Ron's 
gizmo in with board and read the dial indicator.

A qu
estion for Ron...in your tall skinny hotbox, what is your heat source and 
where is it located in the box. My box is similarly shaped, but I don't like 
putting the heat source at the obvious place, ie the bottom, right up close to 
the bottom of the board.  
--
Jim Ialeggio 
www.grandpianosolutions.com
Shirley, MA (978) 425-9026

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