Replies

1. 
   notDusty | Jan 03, 2005 03:58am | #1

               John ,

         That's a tough one , did you rip 3 slats out of each 1" thick board ? I will ask the obvious , did you take even amounts off of each side when planning ? The slat from the center in theory should be the most stable . Also was the stock completely dry , if not  that can cause bowing . If there is any bow before you work a board IMO it ,and all slices from it will be bowed . Reading a board is a time learned skill. My feelings on it even if a board has a hook or is banana shaped side to side or an obvious bow , I won't use it for certain applications. There are many thoughts on the subject but I have never successfully removed any major bows or warpage , seems as though it always comes back. I am under the belief that White Oak takes much longer to dry then say Red Oak . Actually my supplier told that White is air dried for about 2 years depending on the thickness before it is KD. The good thing about White Oak is the beauty especially of Q sawn and the fact that it takes a finish beautifully. If your board was flat until resawing I would tend to lean on the moisture content or RH factor was not optimal.

               good  luck                    dusty

1. 
   jcfd1st | Jan 03, 2005 04:34am | #2

   Dusty:  I made just two slats per board and, as best I can recall, I did plane each side evenly.  What I do remember is seeing the bow as I was resawing.....I should have known then I was in for problems...I did think it would "plane out".  My shop is a double wide garage and I store lumber on the floor....Not directly on the floor but stickered with some 2X2...Maybe it is moisture...It has been quite cold the past week, and my "day job" only allows me weekends in the shop....Do you think the cold temperture, the location of my stored wood and the "weekend only" heat have something to do with the bowing??

1. 
   notDusty | Jan 03, 2005 06:35am | #3

                   John ,

          The moisture content in wood tends to change as the RH factor (relative humidity) changes . So if the wood was KD when you purchased it , after changing locations to your garage / shop perhaps a bit more moisture was retained causing the problem. I would sticker the stock up say 6" more or less especially if you are on a cement slab. More moisture will exist near the slab for sure . Was the wood KD ? Was it really flat when you got it ? Another thing that may have contributed to the bow , the moisture content was no longer centered in each slat , I know that sounds fishy but it is a real possibility. Perhaps if you used the wood by planning some off each side and maybe made each slat 1/2" instead of 1/4"  then the moisture content would remain in the center of the stock . Try running a piece like that and see if it also bows or stays flat. Maybe you could change the dimentions a bit for the slats or waste a lot more and keep them 1/4". Lastly bring a board into the house or another heated atmosphere and try the same process again .Maybe making shelves on the wall or stick them up in the rafters .

                good  luck                 dusty

2. 
   VomSorb | Jan 03, 2005 05:19pm | #4

   Quarter-sawn lumber is as prone to bow as flat-sawn lumber.  It's stability is typically across grain where it shows less cupping.

   Resawing is always a crapshoot so to speak.  It's best done very early in the project so that problems show up before the critical stage. 

   Bow is the worst defect there is in my opinion.  The only answer is replacement of the parts in most cases.  Once you've planed to thickness and then the piece bows there really isn't much you can do.

   You'll do better if you simply plane the new parts to appropriate thickness taking equal amounts off of both faces.  This may be considered 'wasteful', but what you have on hand now is a loss anyway.

   Resawing for regular dimensioned wood (say 3/4, 7/8, etc.) from thicker lumber is fraught with potential problems.  I gave it up a long time ago and only resaw for veneer these days and rarely at that.

   Try to buy what you need in the thicknesses you need and you will be much happier.  If the wood is flat at the yard, it will likely stay flat in your shop, assuming you don't resaw it of course.

    

    

   
   

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   Edited 1/3/2005 2:08 pm ET by cstan

1. 
   AlanMikkelsen | Jan 03, 2005 09:41pm | #5

   I hate to sound pessimistic, but I agree with cstan.  You've released some stresses from a board and gotten bowed slats.  It happens.  I've tried, but cannot predict it on either walnut or white oak.  I've actually had less problem with the oak, than with the walnut, though.  For whatever reason (maybe because it's used as frame and not slat in my work) cherry has probably caused me the least problem. Alan & Lynette Mikkelsen, Mountain View Farm, est. 1934,  Gardens & Fine Woodworking, St. Ignatius, MT