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Do you sticker Kiln dried wood?

9.8K views 16 replies 14 participants last post by  Karson  
#1 · (Edited by Moderator)
In my workshop pics, Bent noticed I stickered my kiln dried wood. He heard that you shouldn't sticker kiln dried wood because it can actually let moisture back into the wood, but both of us aren't quite sure. Has anyone else heard of this or know if it really makes a difference?

Eric
 
#3 ·
how else would you get the moisture out of the middle of the pile ?
except to wait forever ?
 
#5 ·
I forgot to mention that my shop is heated and air conditioned so the humidity is low. My basic theory is that in general wood can't/won't get too dry. If your shop is not temp controlled all the time, then what I said may not be applicable.

Also, Eric said that he has kiln dried wood, so his is already dry - doesn't have to worry about the middle of the pile, David :).
 
#6 ·
In theory, having it stickered should be better, as it will more quickly acclimate to changes in shop humidity levels. The more acclimated it is to the current humidity levels, the less movement you should see when milling it.
 
#7 ·
yeah, i wasn't sure. a worker at a local saw mill said not to sticker kiln dried lumber, because the humidity in the air would raise the moisture content back up to air dried levels. but i guess it makes sense that it will happen regardless, and if doesn't acclimate evenly, it could warp. kind of like air drying in reverse? it could be an issue, being that we live in indiana and our weather/humidity flucuates so much.

sorry to bring up incorrect advice eric.
 
#9 ·
I would think that you want it to come back to the natural moisture level of your shop to prevent warping. Stickering would allow this to happen quicker and prevent the outside of the pile from having a different moisture content than the inside.

Kiln drying still changes the structure of the wood keeping it from leaking sap. It is different than air dried even if the moisture content is the same for both.
 
#10 ·
No matter how old, or how it was dried, lumber will always seek to reach equilibrium with its surrounding environment. By stickering the kiln dried lumber, you are ensuring that as the lumber absorbs moisture from its surroundings, it does so in an even manner, preventing warping, cupping, and checking. Kiln drying only dries wood in a quicker fashion than air drying, and is capable of drying wood to moisture contents below the existing air environment. When kiln dried wood at 6% to 8% MC is placed in a shop or home with a higher MC, the MC will rise to reach equilibrium.

You never want to work wood until it has reached equilibrium, because it's going to move until it does.

The short answer…....YES…..always keep your lumber stickered for best results, unless you are going to shrink wrap the entire stack to prevent any moisture absorbtion. This is done in commercial applications during shipping of large quantities of kiln dried lumber, to keep any MC changes at bay.
 
#11 ·
Eric,

The moisture content of wood depends on the temperature and humidity of the air in which it is stored (EMC).

If the moisture content (MC) of your wood is the same as the EMC of your shop, then you can dead stack (no stickers). The wood will not shrink or swell. This assumes that your shop's temperature and humidity don't change much.

For example, if the wood is at 7% moisture content and your shop stays at 70 degrees (F) and 35 percent relative humidity, the wood will not move because the MC and EMC are equal. But, prolonged changes in temperature and/or humidity will allow the wood to gain or lose moisture. For EMC values at different humidities and temperatures, Google "EMC Table".

The next problem is the environment that the finished piece will live in. In a perfect world, the EMC of the kiln, your shop and your house would all be the same and the moisture content of the wood would never change. In the real world, the EMC of the kiln and the house are pretty close to each other, but the shop's is different. Here in Virginia, my shop's EMC is higher because the outside humidity is higher and I don't constantly control the shop's climate.

Jeff's suggestion to wrap the wood in plastic while it's in the shop is a good one. This will almost eliminate the movement of water between the air and the wood. The MC won't change as the wood goes from the kiln, to your shop, to your house.
 
#12 · (Edited by Moderator)
Once its been kiln dried, you dont have to sticker it. Most of the moisture has already been removed so the wood is fairly stable after that. Also, David Marks has a nice wood shed and none of his wood is stickered. Its stood on end after being kiln dried. In the process of building a project, after milling the lumber i sticker it for a coulpe of days before milling it to final thickness.
 
#13 · (Edited by Moderator)
I have learned when I worked at a lumber yard that both air dried and kiln dried always
get sticked so the air flow thruogh it and ceep the moistre equel in the hole stack
and it prevent warping and other nasty thing´s to happen´s and the stick´s have to bee
abaut a foot betwin them and always have to lay vertital over ich other to prevent bowing
and have some exstra load´s on the top layr as well just to prevent all those nasty thing´s
and I stick to that :)

Ed you still have to take it of one or two weeks before to let it be equel to your shop
before you can work with it

Dennis
 
#15 ·
I skip plane lumber to 1 in thick when it comes out of the kiln. It them goes into one of my storage buildings and is stacked with out stickers. When I have a project coming up I bring it into the shop and stick it in 18 in wide stacks to acclimate for 2 weeks or longer , if time permits.
 
#16 ·
I only sticker wood that needs to dry. Not wood that is already dry. I also can't see why wood from the center of a pack would warp when being pulled out and it naturally takes on moisture from it's environment. As pointed out previously, wood will strive to reach EMC of it's environment no matter whether it starts at 6% or 12% moisture content and no one starting point is more likely to result in a defect in the wood (warping) when moisture is being reintroduced naturally.
 
#17 ·
I've never stickered mine. But even my air dried wood is not stickered after it lost all of it's original moisture. Besides it takes too much room.