# expansion / contraction



## ecw (Jun 15, 2009)

pecan/hickory . does anyone know about how much movement there is for 3/4" x 3" pecan/ hickory. i have some hardwood that has not yet been conditioned(climate controlled), but i want to make a few cabinet doors with it. i have never made doors with unconditioned wood and i know that i would only have to wait for a week or two but i'd like to start working with it tomarrow.
eric


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## Just Bill (Dec 29, 2008)

If it has been outside, I would wait a bit.


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## woodnthings (Jan 24, 2009)

*Check the moisture content*

I see that you are in Texas, hot-dry or hot-humid? Use a moisture meter to check the content. Was it stored under cover?, how thick it is it?, just milled? All this determines if it will be suitable for use.:thumbsup: bill
FYI 1" thickness requires about 1 year to air dry from sawmilling.


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## Daren (Oct 14, 2006)

Like was mentioned your location, the woods current moisture content, the relative humidity of the place the finished product will spend the rest of its life in are all factors to consider...but if you normally have to wait until your wood for projects has conditioned I would this time too.

For future reference, for yourself or anyone who stumbles on this thread here are some links with the math and science behind wood movement and moisture content.

Wood shrinkage explained 

shrinkage/expansion calculator

Wood moisture calculator at EMC (equilibrium moisture content)

L--Longitudinal; R=Radial; T=Tangential are the directions wood moves as mentioned in the calculators.









The way wood is sawn out effect the shrinkage/expansion rates too. Flat sawn moves more that quartersawn. The EMC calculator is very helpful in this case, I would estimate the final installation places average relative humidity and temp. That will tell you how dry/wet the wood will be in service. Compare that to it's current moisture content, too much of a difference one way or the other and you will have some movement...Having said all that construction techniques can allow (should allow) for contraction/expansion.


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