A basic wood acclimatization question.

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JJ1

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I've just made my first purchase from a timber yard (Yandles). It's a 3 meter length of kiln dried oak. I've been advised to leave it indoors for at least three weeks, longer if possible, before using it.
My question is. Is it better to leave it as it came, i.e. in one long plank, or would it be better to trim off both painted ends and perhaps cut it to very rough oversize dimensions, assuming that this may speed up the drying process?
Any advice would be appreciated, thanks.
 
I've always worked on the mantra; "Leave as Long as Possible as Long as Possible"

If you cut it and don't seal the ends then any end splitting will be encroaching on your work piece, although that should be a very a small risk for kiln dried* stock.

* Although Kiln dried you have no guarantees as to its handling and storage since.
 
Interesting that they told you this. If its kiln dried it should be ready to use. We get our oak from Brooks Bros and it's checked with a moisture meter if it's too high it's returned. 3 weeks indoors won't dry it much more unless is half inch or you got central heating ramped up
 
If it's a rough sawn board it's sometimes difficult to know exactly where you'll make the cross cuts to get the cutting list lengths, because there could be knots or grain issues lying unseen beneath the saw marks and general grime that will influence your cross cut decisions. If it's a valuable board sometimes I'll do some rough clean up first with a hand plane to be completely confident about where I'll make the final cross cuts.

If it's a clean board, so you can make the cross cuts without risking any surprises, then it'll acclimatise that bit faster plus you'll lose less of the board's thickness when you come to plane and thickness it down to finished dimensions because wind is minimised in shorter lengths.
 
I'd give it a quick skim on both sides in the thicknesser so that you can see what you've got as Custard says.
Rough sawn boards can sometimes hide some awful defects/surprises, as I've recently found to my cost with some Walnut boards I bought for a staircase.
 
In general it is best for timber to aclimatise close to its finished size. So if you have a wide plank, which you are cutting into multiple widths, then rough saw it to section (but leave it overlength) and then plane it when you are going to use it.

There are 2 aspects to this, firstly boards of kiln dried timber will often exhibit a certain amount of tension, which when you rip into smaller pieces is suddenly released. This is the reason that it is always best to buy timber near to the finished thickness. Buying some 2" boards and deeping into 3 pieces is likely to result in some severely cupped boards.

The second aspect is that timber should have the moisture content that matches the RH of its final place. If there is much of a difference the timber will move as its moisture content attains equilibrium. This is not going to be much of a problem if you are using kiln dried stock on a projectintended for a centrally heated house, unless the work is being done in a damp workshop. Much more of a problem is using kiln dried timber and then making some garden gates
 
ComfortablyNumb":g46m7i2s said:
Interesting that they told you this. If its kiln dried it should be ready to use. We get our oak from Brooks Bros and it's checked with a moisture meter if it's too high it's returned. 3 weeks indoors won't dry it much more unless is half inch or you got central heating ramped up

Hello,

I don't agree,

If it has literally just come out of the kiln, with a moisture content of about 10% plus or minus 2 then use. But kiln dried and stacked for an unknown period in unheated open sheds (as most wood yards store timber) the moisture content will be somewhat different. Bringing the timber into an envioronment similar to where it will finally reside as a finished product, for about 2-3 weeks is a good bet. I would dimension the timber into slightly oversised pieces, if at all possible, and let them acclimatise that way for as long as possible, giving them a final finish dimensioning just before use in the project.

Mike.
 
Depends where its been stored previously.

If the moisture content is the same as where you will be keeping the wood then i dont see why you cant use it straight away. A lot of timber places are likely to storage the wood in unheated sheds where the moisture content of the air will be the same as outdoors.
 
by the sounds of it, you lot could do with one of these

llwrdyk.jpg


Stanley no.70

excellent for scraping boards to show whats underneath the woolly crud!

adidat
 
If you have a plan and a cutting list you could cut it up to near finished sizes (plus the usual margins) as the smaller it is the faster it dries. Whatever you do DON'T plane or thickness until reduced to cutting list sizes.
 
Rough out a little over size then leave to acclimatise in stick for as long as you can spare. Bare in mind kiln dried can be too dry and take up moisture before reaching equilibrium. This all presumes a workshop thats as dry as the pieces resting place.
 
As a matter of interest I have today checked some 10" X 1" Oak Planks (one face planed) that I procured at Yandles on Friday and they are between 10% probed on outer surfaces and 15% in the cut ends where they were cut to transport.
 
CHJ":1e6n7k6v said:
As a matter of interest I have today checked some 10" X 1" Oak Planks (one face planed) that I procured at Yandles on Friday and they are between 10% probed on outer surfaces and 15% in the cut ends where they were cut to transport.


That's useful to know, thanks. I haven't got a moisture meter yet so I wouldn't have had a clue as to moisture content.
What sort of moisture level should I be aiming for? The intended use is 6cm wide edges for an oak veneered MDF desktop situated in my bedroom.
 
My two meters are of the budget variety and not fancy species calibrated versions used by the kiln drying fraternity but they are accurate enough for my needs and wood at those levels would be OK for my turning projects considering that moisture in adhesives on my small sections and process induced heat and drying means they usually settle without undue movement by the time I'm completed.
 
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