Five ways to connect base with top while allowing for seasonal wood movement
Synopsis: To avoid a cracked tabletop, attach it in a way that allows for seasonal movement. Garrett Hack details five solutions. He offers a quick guide to how and why wood moves; then he explains the five methods: pocket holes (for small tables), screw blocks, buttons, dovetail blocks, and metal fasteners. He includes reasons to use each method and talks about their disadvantages, too.
I’ve repaired quite a few antiques, many of them tables with cracked tops. And the reason for the crack is always the same: The top had been attached to the base without any allowance for the wood to move.
Properly attached, a tabletop can expand and contract with changes in humidity while staying flat and firmly connected to its base. Tables that are properly connected gain strength from their connections, the top lending rigidity to the base and the base reinforcing the top.