Just for the yahoo of it, a small tidbit in the MC adventure follows. The mechanical MC gauge I have made, but not yet calibrated is made from a spruce panel out of an old M&H upright. It measures 46" by 6" by 5/16" thick. I dried it to what I think was about 5% MC (maybe a little less). I then laid it on a flat table and glued two ribs to it that measure the full 46" length by 7/8" wide and 5/16" thick. It has been rehydrating now for several weeks in my shop and should yield an EMC of approximately 8.4%. The amount of crown in the panel appears to have been stable for a week or two now. My gauge has a full 2-5/8-inch crown. I was excited after a day or so when it had a good 1/4" of crown, but I find it rather amazing that so much crown would develop with an apparent change of only 3.5% MC. I'm sure a large part of the large crown development is because all my dimensions are reasonable for a real soundboard, except for my rib thickness which is perhaps 1/3 of where it might be on a piano. I'm looking forward to this gauge being of very good use after I get it calibrated - which will occur after we get all this MC mucky-muck worked out to some degree of satisfaction. Terry Farrell
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