The water content of wood we use in CNC work is obviously important for many reasons. One is that the quality of router cuts, and the depth of LASER cuts, will be adversely affected if the wood is wet. Also, and maybe more important, is that wood will change length as the water content changes, and as different woods shrink and expand at different rates that can lead to a nicely finished project coming apart over time (or even a lovely finish cracking). And it can have some bad effects on some finishes causing slow drying or cloudy clear-coats. For those reasons I decided to invest in a moisture-content meter so I can get an idea of how dry my wood is before using it, as well as to let me monitor changes as the wood acclimatises to indoor life before I cut it.
The one I got was only a few pounds on eBay so I’m not expecting really accurate readings, but testing some thin wood sheets at home I’ve been getting sensible readings between around 7% and 12% so hopefully it’ll be useful. Using it is very easy once set to the wood mode: the two metal pins are pushed into a non-vital area (end-grain is a good place too) like in the photo below and, after a moment, the reading appears on the small LCD display. Personally I’m quite happy with it and with a little luck it’ll provide me with a good idea whether my wood is too damp to want to use and let me monitor it to make sure I know when it’s ready for a project.