A reader from Washington State commented:
I'm just getting started making small boxes and practicing with Oak from old pallets. At 73 I'm a bit old to be starting this but I've found I really enjoy making boxes. I'd like to get good at this so I'm reading and watching everything I can and came across your site and purchased your books. Got my wood all milled down just shy of final dimension and I've been letting it sit and now I'm getting some bowing and twisting.Pallet wood can have some disadvantages. It’s free, but often not without costs. Pallets are often made of lesser quality woods and nailed together green, so stresses in the wood are constrained as long as it’s held tightly together and then are released when cut apart.
I was surprised old pallet wood would do this especially after it has been sitting in a metal shed on my ranch. Seems like the more you mill down your wood the more you release it and get the deformities. I'm using my Incra I-box jig and have done a number of plywood boxes with success and a couple of pine boxes successfully but this is the first time with Oak. I guess my choice is to mill it down some more and not let it sit or try to see how it comes out the way it's milled now.
Appreciate any help/insight.
Wood in pallets also is cut thin and dries quickly, so it could suffer the same problems that can result from kiln drying at too fast a rate. That effect is called “case hardening,” in which the inside of the wood and tensions on the surface of the board are inconsistent. Jointing and planing can release tension in the wood in that case.
When wood is stickered and dried, either properly in a kiln or just stacked in the barn, it gets air circulation on all sides but is still free to move some as it dries. If using pallet wood, you might go for a more rustic look, and save the finer techniques for finer wood. I think that trying to do the joinery quickly before the wood changes can be a formula for disappointment. Warping wood is a powerful force that can distort the shape of a box or cause it to break apart. When it comes to wood, each piece is unique, and worthy of scientific examination.
I have no definitive answers. Have fun, and if you get a pallet wood box to hold together, send me a photo.