Perhaps of interest to woodturners.
I got some waxed 1" square Ebony blanks from Pete Kekel (Big Monk Lumber in KY) with unknown moisture content. Waxed wood blanks can be anywhere from green to dry and I find it difficult to guess with hard exotics. My pinless moisture meter needs a bigger contact area so I decided to use the oven-dry method which gives the absolute moisture content independent of the density of the wood. This method is always accurate and cheap if you already have the simple equipment on hand.
If not familiar with this, basically a wood sample is first weighed then gently dried in an oven and weighed repeatedly until the weight quits changing. Then subtract the dry weight from the wet weight and divide that by the dry weight to get the moisture content.
I cut away the surface wax and cut samples from one of the Ebony blanks. A toaster oven dried the wood. I put a thermocouple in the oven to monitor the temperature which needs to be between 212 and 220, ideally 217. The little scale is good to 0.1 grams (checked with my triple-beam balance).
Oven_dry_MC_ebony.jpg
Since I couldn't watch it all the time I put the toaster oven on the concrete floor in my shop office to keep it away from combustibles. I checked the temperature every few hours and quit when the weight was unchanged over two readings.
The moisture content of this Ebony was just over 13% which matched the expected equilibrium MC of air-dried lumber in both TN and KY for this time of the year. I'm glad to know I can turn these without further drying.
If interested in more detail: https://ir.library.oregonstate.edu/downloads/jm214q048
Note, to be clear this is not a drying method for blanks, but a destructive testing method best used a lot of similar sized blanks that have been cut at the same time and stored under the same conditions. It's sometimes used to test a kiln load of wood. When complete, the test sample is bone dry at 0% moisture and may even develop cracks from the process, depending on the wood and starting moisture. For lots of larger pieces like thick squares or slabs the sample is best taken from the center of one piece. It would be perfect to test the MC for a shelf full of box blanks of the same species all air dried under the same conditions. It is also perfect for determining the actual moisture gradient through a thick timbers. Hoadley's "Understanding Wood" is a good book for understanding all this and why it is important, whether you turn green wood or dry. I mostly turn dry.
JKJ
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