I am am making an arts and crafts coffee table out of quartersawn oak and have 3 190mm boards I am edge joining for the top and will be adding breadboard ends.
Two of the boards are perfectly flat bit one has a slight bow and twist (moved after initial prep). I am already down to 22mm and dont want to go any thinner and the warped board varies about 3mm at the worst spot.
My question is, if i glue as is will the breadboard end straighten the top or am I just asking for trouble. I have some spare wood of same thickness but would need to use 2 narrower pieces and colour and figure are much less of a match.
Any advice or suggestions welcome
Of this I can speak on the basis of experience. The obstreperous board was probably cut from reaction wood, and will strive to return to its warped status irrespective of the number of flattening procedures. (Firmly believe that wood rejected by the furniture industry and professional cabinet makers has a tendency to end up on the hobbyists’ workbenches.)
Apart cutting my losses, and prepare a fresh piece, there has been some success with a combination of forcing the warping item and sequestering it between two other boards.
Perhaps the skewness can be reduced by screws coming from the aprons (apron screw holes to be elongated)
Shocking with a heavy hammer against a protecting piece of wood during glue-up is very helpful, as demonstrated in several videos on WWMC.
Cauls, while gluing up, can help a lot by forcing the boards flat. If slots for wedges are added above and below especially obnoxious warp, further focal pressure can be achieved. Making the cauls quite tall and a tad convex is also beneficial.
Splines always makes edge jointing easier, and will aid in sequestering the warping board. I have been known to use a Domino router to create mortices for loose tenons.
Finally pieces running in stopped sliding dovetails (inside of the aprons), could perhaps be an alternative on a low table? There’s a lovely serving tray showing this on Gallery Goodness.
Thanks for your suggestions. I indeed went with the shocking during set up and am working in the breadboard ends atm. I think i will end up losing about 2mm of thickness. i now have to choose between the knot free side with mild medulary rays and the knotted side with amazing rays. woodwork a constant dilemma 😏