Replies

1. 
   JohnWW | Jun 28, 2007 10:10pm | #1

   Wood will gain and lose moisture depending on the humidity of the air around it, and will expand and contract with the change in moisture, but the wood won't be damaged. 

   To reduce stress on the wood, it should be stickered to keep the gain and loss of moisture on both sides of the boards even.  Sealing the end grain is also a good idea to prevent end checking, a coat or two of latex paint works well.

   John white, Shop Manager, Fine Woodworking Magazine

2. 
   HowardAcheson | Jun 28, 2007 11:04pm | #2

   >> large pile of furniture grade materials. All of it is dry, around 15%.

   That confuses me. If you mean the Equilibrium Moisture Content is 15%, that wood is hardly "dry". Dry wood should measure somewhere between 6-7%.

   The 38% relative humidity in your shop will cause wood in the shop to acclimate at about 6-8% EMC. Wood stored outdoors at 65% will acclimate to about 10% EMC.

   Once wood has gone through it's initial moisture loss process, coating the ends is probably not necessary. If you want to seal the ends, the appropriate material to use is a product called Anchorseal or something similar. Anchorseal is a water emulsified paraffin and is completely impervious to water vaper tranmission. Latex paint is formulated to allow water vapor to easily pass through so is not a good option for sealing the ends of the wood.

   Howie.........
1. 
   forestgirl | Jun 30, 2007 06:08pm | #4

    Page 32 of this document may help put the use of latex vs other coatings in perspective.  It's pretty apparent that one coat of latex paint of any sort does little or no good, but it's possible that two or three coats of the right type of latex might provide enough protection that the ends would not check (see "Acrylic flat latex house paint").  My question would be "How much do we need to slow down the loss of moisture from the ends to keep the wood from checking?"  I'm pretty sure that complete impermeability to moisture is not necessary.  Although latex might not be the best choice, compared say to an oil-based alkyd paint, there are plenty of people who use it and it's completely possible that applied properly, it can work.

   This would especially be true of wood that's already approached it's final level of dryness, as is the case in this thread. A freshly felled and milled tree might prompt the use of something impervious or nearly so (see paraffin wax, at the bottom of the list, or of course the Anchoseal).forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-) 

1. 
   HowardAcheson | Jun 30, 2007 07:35pm | #5

   >> My question would be "How much do we need to slow down the loss of moisture from the ends to keep the wood from checking?" I'm pretty sure that complete impermeability to moisture is not necessary.The objective of end sealing is to cause wood in the end of the log to lose moisture at the same rate as the wood in the center of the length of the log. To do this, requires that the end be virtually completely sealed to moisture migration. The forces the moisture to migrate to the circumferal surface of the log just as it does at the center of the length of the log. As it can take months for this moisture migration, using a latex--even the best--which allows migration in days or weeks, would not accomplish the goal.

   >> Although latex might not be the best choice, compared say to an oil-based alkyd paint, there are plenty of people who use it and it's completely possible that applied properly, it can work.The idea of using latex paint came about years ago when latex was first available. Because it was designed to be air permeable to prevent bubbles and cracking as moisture went through walls, folks thought it could sort of meter the amount of moisture tranmission. But, the Forest Product Lab has found that complete moisture blockage is the best. >> This would especially be true of wood that's already approached it's final level of dryness, as is the case in this thread.May be but I have never end sealed wood that I planned to use in a couple of months. For longer term storage, I use some old oil based varnish or oil based paint.Howie.........

   Edited 7/1/2007 5:07 pm ET by HowardAcheson

1. 
   DHAM | Jul 05, 2007 08:16pm | #6

   At 15% moisture, if you sticker it in your shed, it is unlikely to pick up any appreciable moisture.  In fact, it will probably dry a little.  I have 10,000 board feet stacked in sheds at my barn, and the equilibrium moisture content is about 12% (Middle Georgia).  The range is 10% to 15%, so, in my opinion, you will be OK to store it in the shed.  When you anticipate using it, you can bring what you need inside and sticker it to let it acclimate and get below 10% moisture.

1. 
   user-157272 | Jul 06, 2007 04:55am | #7

   Thanks to all who replied. I moved some to the shed and kept some inside.

   Will check the moisture as the year goes on and see what develops.

    

   Thanks again

   Jim

3. 
   oldusty | Jun 30, 2007 05:31pm | #3

   Jim ,

               More then ever it will be important to bring the needed material into the shop to stabilize indoors in the shop before using it .

         The RH (relative humidity) factor will change as the ambient moisture changes .

       The 15% mc may seem dry but I would suggest 6 - 9 % being better more importantly by allowing it to acclimate and stabilize in your shop before working it to final dimensions .

                       good  luck                dusty