Replies

1. 
   DougF | Apr 13, 2005 05:15pm | #1

   A shift in the humidity level of a piece of 12" solid cherry of 9 percentage points from a really dry 6% moisture content will cause the wood to shift about .23".  Glue-ups of multiple narrow pieces will move less.  The only assurance is that the wood will move unless it is maintained in the same temperature/humidity environment in which it is being built.  Since you say that you have no options, finish the piece and hope for the best. 

   Doug 

1. 
   MarkRoderick | Apr 14, 2005 08:32pm | #2

   "Glue-ups of multiple narrow pieces will move less."

   This is the second time in a few days I've seen someone say that on Knots, and unless I'm missing something it really isn't true. If I take a 20" wide board and rip it into narrow pieces, then glue them back together, that glued-up board is going to move just as much as the wider board would have moved.

   I think what you're saying is that if you're working with lots of narrow pieces, the chances are better that the grain on at least some of the pieces will be more quarter-sawn and less flat-sawn, so taken together they'll move less than one large flat-sawn piece. Isn't that what you mean?

1. 
   DougF | Apr 14, 2005 08:55pm | #3

   The glue line itself acts as a moisture barrier and reduces the amount of moisture that moves from one piece to the next.  Differnt grain/fiber orientation from piece to piece also has an effect.  Ay least thats what my books state.

2. 
   HowardAcheson | Apr 14, 2005 09:33pm | #4

   Mark, I agree with you. We did exactly as you suggest about 15 years ago in a woodworking club I belonged to. We used red oak and maple. As I recall, the boards were 12" wide to start with. We left a couple of feet whole and ripped a couple of feet the rest of board into 2" wide boards and reglued them. We then put them in a high humidity room for a couple of weeks. Both boards expanded the same amount within a very small fraction.I don't see how a glueline could impede the transfer of moisture. The moisture will change the fastest from the thinnest section not along the width.Howie.........

2. 
   frenchy | Apr 15, 2005 02:31am | #5

   Agrifffee,

        If I understand your thought process you have several solutions not mentioned so far.. First is the piece strong enough not to deflect under load with out the glue?  well there are two solutions since this is gonna be on the back of the piece (and thus not shown)..

       First you could drill some slightly elongated holes in the back panels and then put slighlty smaller screws with larger washers in to hold the piece in place but allow for expansion  (you could do that at any time but I'd do it before you finish it)  or if the back is going to show you could glue a cleat under the top to hold the load and keep everything from deflecting..