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I’ve been drying small green freshly milled boards in my kitchen oven (typical 1/2” x 3” x 12” quatersawn). It’s working well.

However, I never really get repeatable readings out of my moisture meter and don’t trust it in general, so I have been drying until the weight stops appreciably decreasing for awhile. This leaves the boards pretty bone dry after about 20-30 hours in the oven.

My question is: After I do this but before I plane the boards, should I leave them sit out in the open air (maybe a week or two) to reabsorb moisture from the air?

The reason I ask is I am not certain if I am over drying the boards or not, and if I were I’d be concerned that they’d “un-warp” a small amount after I built something with them as they absorbed moisture from the environment.

  • 1
    also forgot to add: the hotter/dryer your oven and the thicker your wood, the more of a moisture gradient you will get in each piece. A problem you will run into at the extremes is cracking and surface checking. but even without those, you would want an equilibration time post-oven to equalize all parts of the wood to itself as well as the ambient environment. – aaron Aug 22 '18 at 13:51
  • @aaron I do have a good scale. – Jason C Aug 23 '18 at 11:48
  • You say you don't trust your moisture meter, I'm curious what meter are you using? I first used a cheap pin meter I bought from Amazon years ago and definitely got what I paid for. I've shopped around for years until I found a great pinless wood moisture meter from Wagner Meters. They're a little more expensive than others but totally worth every penny. Plus it comes with a 7-year warranty so it makes me feel a lot better about forking over a decent amount for a moisture meter. – lostInTheTetons Jul 8 at 20:50
  • extech mo50 i.e. cheap pin meter I bought from amazon; thinking back it's more that I didn't trust my technique + didn't (and still kind of don't) understand the variations across a piece of wood or even throughout a day. Thanks for the product tip btw; bookmarked for a day when I have more money. – Jason C Jul 8 at 22:36
  • Btw welcome to the site!! Your post will probably get converted to a comment; the format here is a little different than most forums; but it'll make sense after a while. Have fun!! :D – Jason C Jul 8 at 22:41
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My question is: After I do this but before I plane the boards, should I leave them sit out in the open air (maybe a week or two) to reabsorb moisture from the air?

I think it's certainly advisable, and other than the wait there's no downside to doing this so you lose nothing but a bit of time if you take this extra step. And kudos for realising already it may take a couple of weeks, that just a day or two wouldn't be enough.

The wood should ideally be stickered during this stage to allow both faces of the boards easy access to air, and if there is concern they might warp put significant weight on top (centred on the stickering, or right over the top with sticks underneath to transfer the load down at the right spots) to help minimise this, possibly prevent it.

The reason I ask is I am not certain if I am over drying the boards or not

You probably are in some cases. This isn't fatal by any means but it can affect the working characteristics of wood, negatively, and as it also wastes power it may be worth slightly altering your approach and deliberately under-drying, letting the last of the drying take place at ambient temperature (again, stickered and weighted) after the oven has done the lion's share of the work.

But if you want to process the material as quickly as possible, the wood is currently turning out the way you want, and you don't mind having the oven running this long then continue. There is one alternative you might want to think about trying however....

Something else to try: boiling
This sounds counter-intuitive to say the least (read: seems crazy), boiling can't actually speed up the drying of wood, can it? But it can because of where the water is held in green wood and what happens to some of it when boiled1.

The hard part of this is usually rigging up something that will allow the boiling of pieces of wood of useful dimensions, but as you're currently processing wood of fairly modest size this will be easy enough for you, and boiling is apparently really good at producing usable wood directly from green in a reasonable timeframe2 without a great expenditure in energy.

More on this in the links below:
Don’t Crack that Bowl, Make Wood Soup Instead (PDF)
drying wood using boiling method...data and charts


1 This is related to why you can't soak previously dried wood and get it as wet as it used to be when green.
2 It should be expected that the smaller the pieces the faster you can use them, with very small pieces you might be able to start working the wood as soon as it's cool enough to handle ^_^

  • I am fascinated by this boiling method. I have another batch that I haven’t force dried yet I’m going to try it on. – Jason C Aug 23 '18 at 12:51

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