Replies

1. 
   4DThinker | Mar 04, 2005 07:37am | #1

   What cause wood to warp is when one side dries faster than the other. 2x4s from a open-air lumber yard are notorious for having an unusually high moisture content. Try not drying them in the sun, because as far as I know there is no way to have the sun shine on both sides at the same time.  Your boards may straighten out if you expose the other side to the sun.  Instead, stack up or lay out the pieces with a spacer between them or at least under them, and let them dry slowly in the shade.  

   Many boards will have internal stresses that will show up as warping when cut to thinner or narrower pieces.  If that's the case then there may be no way to avoid some warping.

    

   Dave B.

2. 
   notDusty | Mar 04, 2005 08:59am | #2

             Pat ,

      Maybe you could try starting out with wood that is already KD . Fir is not a suitable material for that particular application , whether dry or not . Typically Basswood or Ramin is used for the slats in wood blinds. These two species seem to have the stability needed for the slats. Also as was posted above , drying material in the direct sun is risky at best . Just out of curiosity are you trying to make wood blinds from scratch ? or are you replacing some slats in existing blinds ?

                                   good  luck                    dusty

3. 
   forestgirl | Mar 04, 2005 09:17am | #3

   What you are trying to do is difficult, even with kiln-dried wood, let alone the wet 2x4's you find at a lumberyard.  Look at the growth rings at the ends of the 2x4's and I suspect you'll find they are from fairly small trees.  Thinly sliced slats cut from the edges are just bout guaranteed to cup (See Slat A below).  If you can't afford to get some good, kiln-dried hardwood, maybe try this:

   • Let the 2x4's air dry (out of the sun) for a couple weeks or more (depends on what you're climate's like, but they need to be pretty dry)
   • Rip them down the center, let them dry some more. 
   • Look at the growth-rings and find a side you can slice from that will give you a rift-sawn (slightly less than 1/4-sawn) approach (Slat B below).  Avoid anything that looks like the center of a tree.

   My "drawing" (liberal definition) exaggerates the idea, but Slat A is the kind of orientation you're likely to get slicing off the edges of a 2x4.  Slat B is theoretically possible, but you'll have to manage each board.

   View Image

   forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
   Another proud member of the  "I Rocked With ToolDoc Club" .... :>) 

4. 
   CRAIGCONEY_M | Mar 04, 2005 09:20pm | #4

   1)you could try to sticker them in a controlled environment on a flat surface with weights on top  & a fan to move air through them. 

   2)Cut thicker peices , let them airdry, then resaw once MC is lower.

   3)Try 8/4 poplar.  You will likely have more uniform moisture content than a KD 2x4.  With the current volitility & demand of the softwood market, I've noticed the KD 2x4's to be a little higher MC than they used to be. 

   4) Buy VG DF at a yard, this will have low MC and straigh grain.

   Hope this helps

5. 
   WillGeorge | Mar 05, 2005 01:25am | #5

   Not sure it works..... but I slice the stick down the middle.. Let it dry out a day or two.. then 1/4 it.. dry again..  Seems to work..  NO SUN!

6. 
   Jamie_Buxton | Mar 05, 2005 06:18am | #6

   I remember reading of a guy who freeze-dried thin wood!

   He was bandsawing thin slices of green lumber to make bandsawn veneer.   He stickered his slices and put them in his automatic-defrosting freezer.  The slices froze immediately, which meant that they were still as flat as when he sawed them.   Over time, the ice in the slices evanesced, just like the ice in your ice-cube trays, leaving him with dry flat thin lumber.