how to fix a warped endgrain oak countertop??
We have a four-inch thick, 6 foot long endgrain countertop that became dry and the pieces began to separate in places. Thinking that adding back moisture would reverse some of the damage before re-oiling it, my husband let wet towels sit on it all night. It's now warped and has pulled away from the wall on the side and the half wall that it's attached to on the bottom. The glue between pieces is now squeezed up a bit onto the surface. Is it possible to add moisture to the underside so it expands the other direction? Will it return to the original shape as it dries? Can we do anything to fix it?
Let the top dry (w/o direct heat) to let moisture equilibrate. If the entire surface is warped so that it's convex (all bent upward) as opposed to an undulating surface you can try fixing by oiling the underside to even out the warp, if the top has dried out, put plastic on the top to help force oil into underside and prevent additional moisture entering. If the top is undulating indicating differing levels of moisture intake, you'll probably need to let dry out as before and then resurface with a hand plane or sander (this would be a big effort). As far as pulling away from wall or base, the unit should have been installed to allow some movement. You may need to just detach and reattach when dry and flat. Good luck and I'm guessing you learned water is not a way to remoisturize wood, try mineral oil or one of the speciality oil blends that butcher block makers sell for high dollar.