Carefully lay the top down and attach pipe clamps at roughly 1' intervals. Slowly tighten each pipe clamp in a consistent fashion until the gaps disappear. Small amounts of glue can be removed when dry; scrape up any puddled glue with a plastic putty knife. To minimize sanding later, avoid working glue into the top of the wood. Let the top set overnight.
Drill pocket holes from the outer boards to the inner board. Drilling the holes before adding screws prevents the boards from cracking. To create the holes, measure along the sides of the center board. Mark it about every 7 in (18 cm). You will need to use a very long drill bit, about 3 in (7.6 cm) wide, called a pocket hole drill bit. Drill at an angle down through the side boards and into the side of the center board every 7 in (18 cm).
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