Wood shrinks and swells as it adjusts to seasonal changes in humidity, so design and assemble projects with this in mind. Fasten wide tops to cases with hardware, such as that shown, designed to hold securely but still allow wood movement. Screwing or gluing tops tight to a case likely will result in a split top when the wood moves. Tabletop fasteners shown, hold the top tightly but still can slide in the saw-kerf groove to allow for wood expansion across the grain.