Can You Get the Bow Out?
Admit it: You’ve tried flattening sheets of plywood. I have too. I’ve tried weights, clamps, wetting down the concave side, sundrying the convex side and gluing opposing bowed sheets together. Nothing seems to work with any reliability. If the core veneers weren’t in a perfect state of equilibrium and all in harmony when they were bonded together, the sheet has little chance of flattening out. The only recourse is to save the flattest sheets for the largest parts and use the worst sheets in smaller components, minimizing any curvature.